Search results for: methane catalytic combustion

Authors: Abidullah, Basharat Hussain, Jong Seok Kim

Abstract:

Polymer electrolyte membrane fuel cell (PEMFC) is an electrochemical cell, which undergoes an oxygen reduction reaction to produce electrical energy. Platinum (Pt) metal has been used as a catalyst since its inception, but expensiveness is the major obstacle in the commercialization of fuel cells. Herein a non-precious group metal (NPGM) is employed instead of Pt to reduce the cost of PEMFCs. Manganese dioxide impregnated carbon nanotubes (MnO₂-CNTs composite) is a catalyst having excellent electrochemical properties and offers a better alternative to the Platinum-based PEMFC. The catalyst is synthesized by impregnating the transition metal on large surface carbonaceous CNTs by hydrothermal synthesis techniques. To enhance the catalytic activity and increase the volumetric current density, the sample was pyrolyzed at 800ᵒC under a nitrogen atmosphere. During pyrolysis, the nitrogen was doped in the framework of CNTs. Then the material was treated with acid for removing the unreacted metals and adding oxygen functional group to the CNT framework. This process ameliorates the catalytic activity of the manganese-based catalyst. The catalyst has been characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and the catalyst activity has been examined by rotating disc electrode (RDE) experiment. The catalyst was strong enough to withstand an austere alkaline environment in experimental conditions and had a high electrocatalytic activity for oxygen reduction reaction (ORR). Linear Sweep Voltammetry (LSV) depicts an excellent current density of -4.0 mA/cm² and an overpotential of -0.3V vs. standard calomel electrode (SCE) in 0.1M KOH electrolyte. Rotating disk electrode (RDE) was conducted at 400, 800, 1200, and 1600 rpm. The catalyst exhibited a higher methanol tolerance and long term durability with respect to commercial Pt/C. The results for MnO₂-CNT show that the low-cost catalyst will supplant the expensive Pt/C catalyst in the fuel cell.

Keywords: carbon nanotubes, methanol fuel cell, oxygen reduction reaction, MnO₂-CNTs

Procedia PDF Downloads 120

Authors: Jayakrishnan U.

Abstract:

A concept of adding two strokes to a four stroke Otto or Diesel engine cycle presented here for the waste heat recovery in a four stroke internal combustion engine. Four stroke Diesel cycle and Otto cycle engines have very low thermal efficiency due to high amount of energy loss in exhaust and also on the cooling of the engine. It is estimated about 35 percent of fuel energy is lost in exhaust of engine and 30 percent in cooling of engine. So by modifying a four-stroke Otto or Diesel engine by adding two-stroke heat recovery steam cycle is presented here. Water injection is used to get an additional power stroke by partial compression of the exhaust gases at the end of third stroke in a four stroke I.C.Engine. It is the conversion of a four-stroke cycle to a six-stroke cycle. By taking a four stroke petrol engine of known dimensions, an ideal thermodynamic model is used to analyse and calculate the events of exhaust gas compression and following two strokes of water injection. By changing the exhaust valve closing timing during exhaust stroke and analysing it on various points, an optimum amount of exhaust gas re-compression and amount of water injection can be found for maximizing efficiency and fuel economy. It is achieved by changing the exhaust valve timing and finding an optimum amount of exhaust re-compression, maximizing the net mean effective pressure of the steam expansion stroke (MEPsteam). Specific fuel consumption of the engine also decreases increasing the fuel economy. The valve closing timings for maximum MEPsteam is limited by either 1 bar or dew point temperature of expansion gas or moisture mixture to avoid moisture formation. By modifying the four-stroke Otto or Diesel cycle by adding two water injection stroke has the potential to significantly increase the engine efficiency and fuel economy.

Keywords: internal combustion engine, engine efficiency, six-stroke cycle, water injection, specific fuel consumption

Procedia PDF Downloads 298

Authors: Sunil Verma

Abstract:

This report is concerned with study of autoignition delay characterstics of n-pentane. Experiments are done for different equivalents ratio on Rapid compression machine. Dependence of autoignition delay period is clearly explained from lean to rich mixtures. Equivalence ratio is varied from 0.33 to 0.6.

Keywords: combustion, autoignition, ignition delay, rapid compression machine

Procedia PDF Downloads 341

Authors: Raka Rahmatulloh, Mohammad Ilham Nugraha, Muhammad Ifan Fathurrahman

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The agricultural sector covers a wide area, one of them is livestock subsector that supply needs of the food source of animal protein. Animal protein is produced by the main livestock production such as meat, milk, eggs, etc. Besides the main production, livestock would produce metabolic residue, so called livestock wastes. Characteristics of livestock wastes can be either solid (feces), liquid (urine), and gas (methane) which turned out to be useful and has economical value when well-processed and well-controlled. Nowadays, this livestock wastes is considered as a source of pollutants, especially water pollution. If the source of pollutants used in an integrated way, it will have a positive impact on organic farming and a healthy environment. Management of livestock wastes can be integrated with the farming sector to the planting and caring that rely on fertilizers. Most Indonesian farmers still use chemical fertilizers, where the use of it in the long term will disturb the ecological balance of the environment. One of the main efforts is to use organic fertilizers instead of chemical fertilizer that conducted by the Faculty of Animal Husbandry, Padjadjaran University. The method is to use the solid waste of livestock and agricultural wastes into liquid organic fertilizer, feed additive, biogas and vermicompost through decomposition. The decomposition takes as long as 14 days including aeration and extraction process using water as a nutrients solvent media which contained in decomposes and disinfection media to release pathogenic microorganisms in decomposes. Liquid organic fertilizer has highly efficient for the farmers to have a ratio of carbon/nitrogen (C/N) 25/1 to 30/1 and neutral pH (6.5-7.5) which is good for plant growth. Feed additive may be given to improve the digestibility of feed so that substances can be easily absorbed by the body for production. Biogas contains methane (CH4), which has a high enough heat to produce electricity. Vermicompost is an overhaul of waste organic material that has excellent structure, porosity, aeration, drainage, and moisture holding capacity. Based on the case study above, an integrated livestock wastes management program strongly supports the Indonesian government in the achievement of sustainable livestock development.

Keywords: integrated, livestock wastes, organic fertilizer, sustainable livestock development

Procedia PDF Downloads 429

Authors: Mateus Silva Mendonça, Wender Pereira de Oliveira, Gabriel Heleno de Paula Araújo, Hiago Tenório Teixeira Santana Rocha, Augusto César Teixeira Malaquias, José Guilherme Coelho Baeta

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The stricter legislation and the greater demand of the population regard to gas emissions and their effects on the environment as well as on human health make the automotive industry reinforce research focused on reducing levels of contamination. This reduction can be achieved through the implementation of improvements in internal combustion engines in such a way that they promote the reduction of both specific fuel consumption and air pollutant emissions. These improvements can be obtained through numerical simulation, which is a technique that works together with experimental tests. The aim of this paper is to build, with support of the GT-Suite software, a one-dimensional model of a single-cylinder research engine to analyze the impact of the variation of swirl and tumble coefficients on the performance and on the air pollutant emissions of an engine. Initially, the discharge coefficient is calculated through the software Converge CFD 3D, given that it is an input parameter in GT-Power. Mesh sensitivity tests are made in 3D geometry built for this purpose, using the mass flow rate in the valve as a reference. In the one-dimensional simulation is adopted the non-predictive combustion model called Three Pressure Analysis (TPA) is, and then data such as mass trapped in cylinder, heat release rate, and accumulated released energy are calculated, aiming that the validation can be performed by comparing these data with those obtained experimentally. Finally, the swirl and tumble coefficients are introduced in their corresponding objects so that their influences can be observed when compared to the results obtained previously.

Keywords: 1D simulation, single-cylinder research engine, swirl coefficient, three pressure analysis, tumble coefficient

Procedia PDF Downloads 95

Authors: A. Guemache, M. Omari

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Oxides with formula Ca1-xSrx MnO3(0≤x≤0.2) were synthesized using co precipitation method. The identification of the obtained phase was carried out using infrared spectroscopy and x-ray diffraction. Thermogravimetric and differential analysis was permitted to characterize different transformations of precursors which take place during one heating cycle. The study of electrochemical behavior was carried out by cyclic voltammetry and impedance spectroscopy. The obtained results show that apparent catalytic activity improved when increasing the concentration of strontium. Anodic current densities varies from 1.3 to 5.9 mA/cm2 at the rate scan of 20 mV.s-1 and a potential 0.8 V for oxides with composition x=0 to 0.2.

Keywords: oxide, co-precipitation, thermal analysis, electrochemical properties

Procedia PDF Downloads 356

Authors: Parya Nasehi, Mohammad Kazem Mohammadi

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3,4-dihydropyrimidin-2(1H)-thiones were synthesized in the presence of Ag nanoparticle/melamine sulfonic acid (MSA) supported on alumina. The reaction was carried out at 110 oC for 20 min under solvent free conditions. This method have some advantages such as good yield, mild reaction conditions, ease of operation and work up, short reaction time and high product purity.

Keywords: nanoparticle melamine sulfonic acid, Al2O3, Biginelli reaction, 3, 4-dihydropyrimidin-2(1H, solvent free

Procedia PDF Downloads 507

Authors: R. Adwaith, J. Gopinath, Vasantha Kohila B., R. Chandru, Arul Prakash R.

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The turbofan engine is a type of air breathing engine that is widely used in aircraft propulsion produces thrust mainly from the mass-flow of air bypassing the engine core. The present research has developed an effective method numerically by increasing the thrust generated from the bypass air. This thrust increase is brought about by heating the walls of the bypass valve from the combustion chamber using convective heat transfer method. It is achieved computationally by the use external heat to enhance the velocity of bypass air of turbofan engines. The bypass valves are either heated externally using multicell tube resistor which convert electricity generated by dynamos into heat or heat is transferred from the combustion chamber. This increases the temperature of the flow in the valves and thereby increase the velocity of the flow that enters the nozzle of the engine. As a result, mass-flow of air passing the core engine for producing more thrust can be significantly reduced thereby saving considerable amount of Jet fuel. Numerical analysis has been carried out on a scaled down version of a typical turbofan bypass valve, where the valve wall temperature has been increased to 700 Kelvin. It is observed from the analysis that, the exit velocity contributing to thrust has significantly increased by 10 % due to the heating of by-pass valve. The degree of optimum increase in the temperature, and the corresponding effect in the increase of jet velocity is calculated to determine the operating temperature range for efficient increase in velocity. The technique used in the research increases the thrust by using heated by-pass air without extracting much work from the fuel and thus improve the efficiency of existing turbofan engines. Dimensional analysis has been carried to prove the accuracy of the results obtained numerically.

Keywords: turbofan engine, bypass valve, multi-cell tube, convective heat transfer, thrust

Procedia PDF Downloads 353

Authors: M. Bharath, Vasudevan Raghavan, B. V. S. S. S. Prasad, S. R. Chakravarthy

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In this experimental study, effects of addition of rice husk on coal gasification in a bubbling fluidized bed gasifier, operating at atmospheric pressure with air as gasifying agent, are reported. Rice husks comprising of 6.5% and 13% by mass are added to coal. Results show that, when rice husk is added the methane yield increases from volumetric percentage of 0.56% (with no rice husk) to 2.77% (with 13% rice husk). CO and H₂ remain almost unchanged and CO₂ decreases with addition of rice husk. The calorific value of the synthetic gas is around 2.73 MJ/Nm³. All performance indices, such as cold gas efficiency and carbon conversion, increase with addition of rice husk.

Keywords: bubbling fluidized bed reactor, calorific value, coal gasification, rice husk

Procedia PDF Downloads 218

Authors: Ayman Hijazi, Witold Kwapinski, J. J. Leahy

Abstract:

Finding a sustainable alternative energy to fossil fuel is an urgent need as various environmental challenges in the world arise. Therefore, formic acid (FA) decomposition has been an attractive field that lies at the center of biomass platform, comprising a potential pool of hydrogen energy that stands as a new energy vector. Liquid FA features considerable volumetric energy density of 6.4 MJ/L and a specific energy density of 5.3 MJ/Kg that qualifies it in the prime seat as an energy source for transportation infrastructure. Additionally, the increasing research interest in FA decomposition is driven by the need of in-situ H2 production, which plays a key role in the hydrogenation reactions of biomass into higher value components. It is reported elsewhere in literature that catalytic decomposition of FA is usually performed in poorly designed setup using simple glassware under magnetic stirring, thus demanding further energy investment to retain the used catalyst. it work suggests an approach that integrates designing a novel catalyst featuring magnetic property with a robust setup that minimizes experimental & measurement discrepancies. One of the most prominent active species for dehydrogenation/hydrogenation of biomass compounds is palladium. Accordingly, we investigate the potential of engrafting palladium metal onto functionalized magnetic nanoparticles as a heterogeneous catalyst to favor the production of CO-free H2 gas from FA. Using ordinary magnet to collect the spent catalyst renders core-shell magnetic nanoparticles as the backbone of the process. Catalytic experiments were performed in a jacketed batch reactor equipped with an overhead stirrer under inert medium. Through a novel approach, FA is charged into the reactor via high-pressure positive displacement pump at steady state conditions. The produced gas (H2+CO2) was measured by connecting the gas outlet to a measuring system based on the amount of the displaced water. The novelty of this work lies in designing a very responsive catalyst, pumping consistent amount of FA into a sealed reactor running at steady state mild temperatures, and continuous gas measurement, along with collecting the used catalyst without the need for centrifugation. Catalyst characterization using TEM, XRD, SEM, and CHN elemental analyzer provided us with details of catalyst preparation and facilitated new venues to alter the nanostructure of the catalyst framework. Consequently, the introduction of amine groups has led to appreciable improvements in terms of dispersion of the doped metals and eventually attaining nearly complete conversion (100%) of FA after 7 hours. The relative importance of the process parameters such as temperature (35-85°C), stirring speed (150-450rpm), catalyst loading (50-200mgr.), and Pd doping ratio (0.75-1.80wt.%) on gas yield was assessed by a Taguchi design-of-experiment based model. Experimental results showed that operating at lower temperature range (35-50°C) yielded more gas while the catalyst loading and Pd doping wt.% were found to be the most significant factors with a P-values 0.026 & 0.031, respectively.

Keywords: formic acid decomposition, green catalysis, hydrogen, mesoporous silica, process optimization, nanoparticles

Procedia PDF Downloads 47

Authors: Jinhoa Lee

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The relationships between environmental quality, energy use and economic output have created growing attention over the past decades among researchers and policy makers. Focusing on the empirical aspects of the role of CO2 emissions and energy use in affecting the economic output, this paper is an effort to fulfill the gap in a comprehensive case study at a country level using modern econometric techniques. To achieve the goal, this country-specific study examines the short-run and long-run relationships among energy consumption (using disaggregated energy sources: crude oil, coal, natural gas, electricity), carbon dioxide (CO2) emissions and gross domestic product (GDP) for Israel using time series analysis from the year 1980-2010. To investigate the relationships between the variables, this paper employs the Phillips–Perron (PP) test for stationarity, Johansen maximum likelihood method for cointegration and a Vector Error Correction Model (VECM) for both short- and long-run causality among the research variables for the sample. The long-run equilibrium in the VECM suggests significant positive impacts of coal and natural gas consumptions on GDP in Israel. In the short run, GDP positively affects coal consumption. While there exists a positive unidirectional causality running from coal consumption to consumption of petroleum products and the direct combustion of crude oil, there exists a negative unidirectional causality running from natural gas consumption to consumption of petroleum products and the direct combustion of crude oil in the short run. Overall, the results support arguments that there are relationships among environmental quality, energy use and economic output but the associations can to be differed by the sources of energy in the case of Israel over of period 1980-2010.

Keywords: CO2 emissions, energy consumption, GDP, Israel, time series analysis

Procedia PDF Downloads 644

Authors: Adeiza Matthew, Oluwadamilola Abubakar

Abstract:

Wood energy, also known as wood fuel, is a renewable energy source that is derived from woody biomass, which is organic matter that is harvested from forests, woodlands, and other lands. Woody biomass includes trees, branches, twigs, and other woody debris that can be used as fuel. Wood energy can be classified based on its sources, such as trees outside forests, residues from wood harvesting and conversion, and energy plantations. There are several policy frameworks that support the use of wood energy, including participatory forest management and agroforestry. These policies aim to promote the sustainable use of woody biomass as a source of energy while also protecting forests and wildlife habitats. There are several options for using wood as a fuel, including central heating systems, pellet-based systems, wood chip-based systems, log boilers, fireplaces, and stoves. Each of these options has its own benefits and drawbacks, and the most appropriate option will depend on factors such as the availability of woody biomass, the heating needs of the household or facility, and the local climate. In order to use wood as a fuel, it must be harvested and stored properly. Hardwood or softwood can be used as fuel, and the heating value of firewood depends on the species of tree and the degree of moisture content. Proper harvesting and storage of wood can help to minimize environmental impacts and improve wildlife habitats. The use of wood energy has several environmental impacts, including the release of greenhouse gases during combustion and the potential for air pollution from combustion by-products. However, wood energy can also have positive environmental impacts, such as the sequestration of carbon in trees and the reduction of reliance on fossil fuels. The regulation and legislation of wood energy vary by country and region, and there is an ongoing debate about the potential use of wood energy in renewable energy technologies. Wood energy is a renewable energy source that can be used to generate electricity, heat, and transportation fuels. Woody biomass is abundant and widely available, making it a potentially significant source of energy for many countries. The use of wood energy can create local economic and employment opportunities, particularly in rural areas. Wood energy can be used to reduce reliance on fossil fuels and reduce greenhouse gas emissions. Properly managed forests can provide a sustained supply of woody biomass for energy, helping to reduce the risk of deforestation and habitat loss. Wood energy can be produced using a variety of technologies, including direct combustion, co-firing with fossil fuels, and the production of biofuels. The environmental impacts of wood energy can be minimized through the use of best practices in harvesting, transportation, and processing. Wood energy is regulated and legislated at the national and international levels, and there are various standards and certification systems in place to promote sustainable practices. Wood energy has the potential to play a significant role in the transition to a low-carbon economy and the achievement of climate change mitigation goals.

Keywords: biomass, timber, charcoal, firewood

Procedia PDF Downloads 95

Authors: Ayman Hijazi, Witold Kwapinski, J. J. Leahy

Abstract:

Finding a sustainable alternative energy to fossil fuel is an urgent need as various environmental challenges in the world arise. Therefore, formic acid (FA) decomposition has been an attractive field that lies at the center of the biomass platform, comprising a potential pool of hydrogen energy that stands as a distinct energy vector. Liquid FA features considerable volumetric energy density of 6.4 MJ/L and a specific energy density of 5.3 MJ/Kg that qualifies it in the prime seat as an energy source for transportation infrastructure. Additionally, the increasing research interest in FA decomposition is driven by the need for in-situ H₂ production, which plays a key role in the hydrogenation reactions of biomass into higher-value components. It is reported elsewhere in the literature that catalytic decomposition of FA is usually performed in poorly designed setups using simple glassware under magnetic stirring, thus demanding further energy investment to retain the used catalyst. Our work suggests an approach that integrates designing a distinct catalyst featuring magnetic properties with a robust setup that minimizes experimental & measurement discrepancies. One of the most prominent active species for the dehydrogenation/hydrogenation of biomass compounds is palladium. Accordingly, we investigate the potential of engrafting palladium metal onto functionalized magnetic nanoparticles as a heterogeneous catalyst to favor the production of CO-free H₂ gas from FA. Using an ordinary magnet to collect the spent catalyst renders core-shell magnetic nanoparticles as the backbone of the process. Catalytic experiments were performed in a jacketed batch reactor equipped with an overhead stirrer under an inert medium. Through a distinct approach, FA is charged into the reactor via a high-pressure positive displacement pump at steady-state conditions. The produced gas (H₂+CO₂) was measured by connecting the gas outlet to a measuring system based on the amount of the displaced water. The uniqueness of this work lies in designing a very responsive catalyst, pumping a consistent amount of FA into a sealed reactor running at steady-state mild temperatures, and continuous gas measurement, along with collecting the used catalyst without the need for centrifugation. Catalyst characterization using TEM, XRD, SEM, and CHN elemental analyzer provided us with details of catalyst preparation and facilitated new venues to alter the nanostructure of the catalyst framework. Consequently, the introduction of amine groups has led to appreciable improvements in terms of dispersion of the doped metals and eventually attaining nearly complete conversion (100%) of FA after 7 hours. The relative importance of the process parameters such as temperature (35-85°C), stirring speed (150-450rpm), catalyst loading (50-200mgr.), and Pd doping ratio (0.75-1.80wt.%) on gas yield was assessed by a Taguchi design-of-experiment based model. Experimental results showed that operating at a lower temperature range (35-50°C) yielded more gas, while the catalyst loading and Pd doping wt.% were found to be the most significant factors with P-values 0.026 & 0.031, respectively.

Keywords: formic acid decomposition, green catalysis, hydrogen, mesoporous silica, process optimization, nanoparticles

Procedia PDF Downloads 46

Authors: Dmitrii Glushkov, Aleksandr G. Nigay, Olga S. Yashutina

Abstract:

In recent years, due to the intensive development of the Arctic and Antarctic areas, the actual task is to develop technology for the effective utilization of solid and liquid combustible wastes in an environment with low temperatures. Firstly, such technology will help to prevent the dumping of waste into the World Ocean and reduce the risks of causing environmental damage to the Far North areas. Secondly, promising actions will help to prepare fuel compositions from the waste in the places of their production. Such kind of fuels can be used as energy resources. It will reduce waste utilization costs when transporting them to the mainland. In the present study, we suggest a solution to the problem of waste utilization by the preparation of gel fuels based on solid and liquid combustible components with the addition of the thickener. Such kind of fuels is characterized by ease of preparation, storage, transportation and use (as energy resources). The main regularities and characteristics of physical and chemical processes are established with varying parameters of gel fuels and heating sources in wide ranges. The obtained results let us conclude about the prospects of gel fuels practical application for combustible wastes utilization. Appropriate technology will be characterized by positive environmental, operational and economic effects. The composition of the gel fuels can vary in a wide range. The fuels preparation based on one type of a combustible liquid or a several liquids mixture with the finely dispersed components addition makes it possible to obtain compositions with predicted rheological, energy or environmental characteristics. Besides, gel fuels have a lower level of the fire hazard compared to common solid and liquid fuels. This makes them convenient for storage and transportation. In such conditions, it is not necessary to transport combustible wastes from the territory of the Arctic and the Antarctic to the mainland for processing, which is now quite an expensive procedure. The research was funded by the Russian Science Foundation (project No. 18-13-00031).

Keywords: combustible liquid waste, gel fuel, ignition and combustion, utilization

Procedia PDF Downloads 113

Authors: Nalinee B. Suryawanshi, Vinay M. Bhandari, Laxmi Gayatri Sorokhaibam, Vivek V. Ranade

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Deep desulphurization of transportation fuels is a major environmental concern all over the world and recently prescribed norms for the sulphur content require below 10 ppm sulphur concentrations in fuels such as diesel and gasoline. The existing technologies largely based on catalytic processes such as hydrodesulphurization, oxidation require newer catalysts and demand high cost of deep desulphurization whereas adsorption based processes have limitations due to lower capacity of sulphur removal. The present work is an attempt to provide alternatives for the existing methodologies using a newer non-catalytic process based on hydrodynamic cavitation. The developed process requires appropriate combining of organic and aqueous phases under ambient conditions and passing through a cavitating device such as orifice, venturi or vortex diode. The implosion of vapour cavities formed in the cavitating device generates (in-situ) oxidizing species which react with the sulphur moiety resulting in the removal of sulphur from the organic phase. In this work, orifice was used as a cavitating device and deep desulphurization was demonstrated for removal of thiophene as a model sulphur compound from synthetic fuel of n-octane, toluene and n-octanol. The effect of concentration of sulphur (up to 300 ppm), nature of organic phase and effect of pressure drop (0.5 to 10 bar) was discussed. A very high removal of sulphur content of more than 90% was demonstrated. The process is easy to operate, essentially works at ambient conditions and the ratio of aqueous to organic phase can be easily adjusted to maximise sulphur removal. Experimental studies were also carried out using commercial diesel as a solvent and the results substantiate similar high sulphur removal. A comparison of the two cavitating devices- one with a linear flow and one using vortex flow for effecting pressure drop and cavitation indicates similar trends in terms of sulphur removal behaviour. The developed process is expected to provide an attractive environmental engineering alternative for deep desulphurization of transportation fuels.

Keywords: cavitation, petroleum, separation, sulphur removal

Procedia PDF Downloads 374

Authors: Juliana A. B. Silva, Caio H. T. L. Albuquerque, Leonardo L. dos Santos, Cristiane K. Oliveira, Ivani Malvestiti, Fernando Hallwass, Ricardo L. Longo

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Complexes with lanthanide ions have been extensively studied due to their applications as luminescent, magnetic and catalytic materials as molecular or extended crystals, thin films, glasses, polymeric matrices, ionic liquids, and in solution. NMR chemical shift data in solution have been reported and suggest fluxional structures in a wide range of coordination compounds with rare earth ions. However, the fluxional mechanisms for these compounds are still not established. This structural fluxionality may affect the photophysical, catalytic and magnetic properties in solution. Thus, understanding the structural interconversion mechanisms may aid the design of coordination compounds with, for instance, improved (electro)luminescence, catalytic and magnetic behaviors. The [Eu(btfa)₃bipy] complex, where btfa= 4,4,4-trifluoro-1-phenyl-1,3-butanedionate and bipy= 2,2’-bipiridyl, has a well-defined X-ray crystallographic structure and preliminary 1H NMR data suggested a structural fluxionality. Thus, we have investigated a series of coordination compounds with lanthanide ions [Ln(btfa)₃L], where Ln = La, Eu, Gd or Yb and L= bipy or phen (phen=1,10-phenanthroline) using a combined theoretical-experimental approach. These complexes were synthesized and fully characterized, and detailed NMR measurements were obtained. They were also studied by quantum chemical computational methods (DFT-PBE0). The aim was to determine the relevant factors in the structure of these compounds that favor or not the fluxional behavior. Measurements of the 1H NMR signals at variable temperature in CD₂Cl₂ of the [Eu(btfa)₃L] complexes suggest that these compounds have a fluxional structure, because the crystal structure has non-equivalent btfa ligands that should lead to non-equivalent hydrogen atoms and thus to more signals in the NMR spectra than those obtained at room temperature, where all hydrogen atoms of the btfa ligands are equivalent, and phen ligand has an effective vertical symmetry plane. For the [Eu(btfa)₃bipy] complex, the broadening of the signals at –70°C provides a lower bound for the coalescence temperature, which indicates the energy barriers involved in the structural interconversion mechanisms are quite small. These barriers and, consequently, the coalescence temperature are dependent upon the radii of the lanthanide ion as well as to their paramagnetic effects. The PBE0 calculated structures are in very good agreement with the crystallographic data and, for the [Eu(btfa)₃bipy] complex, this method provided several distinct structures with almost the same energy. However, the energy barrier for structural interconversion via dissociative pathways were found to be quite high and could not explain the experimental observations. Whereas the pseudo-rotation pathways, involving the btfa and bipy ligands, have very small activation barriers, in excellent agreement with the NMR data. The results also showed an increase in the activation barrier along the lanthanide series due to the decrease of the ionic radii and consequent increase of the steric effects. TD-DFT calculations showed a dependence of the ligand donor state energy with different structures of the complex [Eu(btfa)₃phen], which can affect the energy transfer rates and the luminescence. The energy required to promote the structural fluxionality may also enhance the luminescence quenching in solution. These results can aid in the design of more luminescent compounds and more efficient devices.

Keywords: computational chemistry, lanthanide-based compounds, NMR, structural fluxionality

Procedia PDF Downloads 195

Authors: Lukasz Grabowski, Tytus Tulwin, Michal Geca, P. Karpinski

Abstract:

This paper presents the radial aircraft engine model which has been created in AVL Boost software. This model is a one-dimensional physical model of the engine, which enables us to investigate the impact of an ignition system design on engine performance (power, torque, fuel consumption). In addition, this model allows research under variable environmental conditions to reflect varied flight conditions (altitude, humidity, cruising speed). Before the simulation research the identifying parameters and validating of model were studied. In order to verify the feasibility to take off power of gasoline radial aircraft engine model, some validation study was carried out. The first stage of the identification was completed with reference to the technical documentation provided by manufacturer of engine and the experiments on the test stand of the real engine. The second stage involved a comparison of simulation results with the results of the engine stand tests performed on a WSK ’PZL-Kalisz’. The engine was loaded by a propeller in a special test bench. Identifying the model parameters referred to a comparison of the test results to the simulation in terms of: pressure behind the throttles, pressure in the inlet pipe, and time course for pressure in the first inlet pipe, power, and specific fuel consumption. Accordingly, the required coefficients and error of simulation calculation relative to the real-object experiments were determined. Obtained the time course for pressure and its value is compatible with the experimental results. Additionally the engine power and specific fuel consumption tends to be significantly compatible with the bench tests. The mapping error does not exceed 1.5%, which verifies positively the model of combustion and allows us to predict engine performance if the process of combustion will be modified. The next conducted tests verified completely model. The maximum mapping error for the pressure behind the throttles and the inlet pipe pressure is 4 %, which proves the model of the inlet duct in the engine with the charging compressor to be correct.

Keywords: 1D-model, aircraft engine, performance, validation

Procedia PDF Downloads 330

Authors: Tibor Ajtai, Noémi Utry, Máté Pintér, Tomi Smausz, Zoltán Kónya, Béla Hopp, Gábor Szabó, Zoltán Bozóki

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Characterization of spectral responses of light absorbing carbonaceous particulate matter (LAC) is of great importance in both modelling its climate effect and interpreting remote sensing measurement data. The residential or domestic combustion of coal is one of the dominant LAC constituent. According to some related assessments the residential coal burning account for roughly half of anthropogenic BC emitted from fossil fuel burning. Despite of its significance in climate the comprehensive investigation of optical properties of residential coal aerosol is really limited in the literature. There are many reason of that starting from the difficulties associated with the controlled burning conditions of the fuel, through the lack of detailed supplementary proximate and ultimate chemical analysis enforced, the interpretation of the measured optical data, ending with many analytical and methodological difficulties regarding the in-situ measurement of coal aerosol spectral responses. Since the gas matrix of ambient can significantly mask the physicochemical characteristics of the generated coal aerosol the accurate and controlled generation of residential coal particulates is one of the most actual issues in this research area. Most of the laboratory imitation of residential coal combustion is simply based on coal burning in stove with ambient air support allowing one to measure only the apparent spectral feature of the particulates. However, the recently introduced methodology based on a laser ablation of solid coal target opens up novel possibilities to model the real combustion procedure under well controlled laboratory conditions and makes the investigation of the inherent optical properties also possible. Most of the methodology for spectral characterization of LAC is based on transmission measurement made of filter accumulated aerosol or deduced indirectly from parallel measurements of scattering and extinction coefficient using free floating sampling. In the former one the accuracy while in the latter one the sensitivity are liming the applicability of this approaches. Although the scientific community are at the common platform that aerosol-phase PhotoAcoustic Spectroscopy (PAS) is the only method for precise and accurate determination of light absorption by LAC, the PAS based instrumentation for spectral characterization of absorption has only been recently introduced. In this study, the investigation of the inherent, spectral features of laser generated and chemically characterized residential coal aerosols are demonstrated. The experimental set-up and its characteristic for residential coal aerosol generation are introduced here. The optical absorption and the scattering coefficients as well as their wavelength dependency are determined by our state-of-the-art multi wavelength PAS instrument (4λ-PAS) and multi wavelength cosinus sensor (Aurora 3000). The quantified wavelength dependency (AAE and SAE) are deduced from the measured data. Finally, some correlation between the proximate and ultimate chemical as well as the measured or deduced optical parameters are also revealed.

Keywords: absorption, scattering, residential coal, aerosol generation by laser ablation

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Authors: Sambit Supriya Dash, Rahul Ravi R, Vikram Ramanan, Vinayak Malhotra

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Combustion in itself is a complex phenomenon that involves the interaction and interplay of multiple phenomena, the combined effect of which gives rise to the common flame that we see and use in our daily life applications from cooking to propelling our vehicles to space. The most important thing that goes unnoticed about these flames is the effect of the various phenomena from its surrounding environment that affects its behavior and properties. These phenomena cause a variety of energy interactions that lead to various types of energy transformations which in turn affect the flame behavior. This paper focuses on experimentally investigating the effect of one such phenomenon, which is the acoustics or sound energy on diffusion flames. The subject in itself is extensively studied upon as thermo-acoustics globally, whereas the current work focuses on studying its effect on soot formation on diffusion flames. The said effect is studied in this research work by the use of a butane as fuel, fitted with a nozzle that houses 3 arrays consisting of 4 holes each that are placed equidistant to each other and the resulting flame impinged with sound from two independent and similar sound sources that are placed equidistant from the centre of the flame. The entire process is systematically video graphed using a 60 fps regular CCD and analysed for variation in flame heights and flickering frequencies where the fuel mass flow rate is maintained constant and the configuration of entrainment holes and frequency of sound are varied, whilst maintaining constant ambient atmospheric conditions. The current work establishes significant outcomes on the effect of acoustics on soot formation; it is noteworthy that soot formation is the main cause of pollution and a major cause of inefficiency of current propulsion systems. This work is one of its kinds, and its outcomes are widely applicable to commercial and domestic appliances that utilize combustion for energy generation or propulsion and help us understand them better, so that we can increase their efficiency and decrease pollution.

Keywords: thermoacoustics, entrainment, propulsion system, efficiency, pollution

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Authors: N. Wijayati, Kusoro Siadi, Hanny Wijaya, Maggy Thenawijjaja Suhartono

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This work describes the lipase-mediated synthesis of α-pinene oxide at ambient temperature. The immobilized lipase from Pseudomonas aeruginosa is used to generate peroxyoctanoic acid directly from octanoic acid and hydrogen peroxide. The peroxy acid formed is then applied for in situ oxidation of α-pinene. High conversion of α-pinene to α-pinene oxide (approximately 78%) was achieved when using 0,1 g enzim lipase, 6 mmol H2O2, dan 5 mmol octanoic acid. Various parameters affecting the conversion of α-pinene to α pinene oxide were studied.

Keywords: α-Pinene; P. aeruginosa; Octanoic acid

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Authors: Iryna Atamaniuk, Hannah Boysen, Nils Wieczorek, Natalia Politaeva, Iuliia Bazarnova, Kerstin Kuchta

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Over the last decade due to climate change and a strategy of natural resources preservation, the interest for the aquatic biomass has dramatically increased. Along with mitigation of the environmental pressure and connection of waste streams (including CO₂ and heat emissions), microalgae bioeconomy can supply food, feed, as well as the pharmaceutical and power industry with number of value-added products. Furthermore, in comparison to conventional biomass, microalgae can be cultivated in wide range of conditions without compromising food and feed production, thus addressing issues associated with negative social and the environmental impacts. This paper presents the state-of-the art technology for microalgae bioeconomy from cultivation process to production of valuable components and by-streams. Microalgae Chlorella sorokiniana were cultivated in the pilot-scale innovation concept in Hamburg (Germany) using different systems such as race way pond (5000 L) and flat panel reactors (8 x 180 L). In order to achieve the optimum growth conditions along with suitable cellular composition for the further extraction of the value-added components, process parameters such as light intensity, temperature and pH are continuously being monitored. On the other hand, metabolic needs in nutrients were provided by addition of micro- and macro-nutrients into a medium to ensure autotrophic growth conditions of microalgae. The cultivation was further followed by downstream process and extraction of lipids, proteins and saccharides. Lipids extraction is conducted in repeated-batch semi-automatic mode using hot extraction method according to Randall. As solvents hexane and ethanol are used at different ratio of 9:1 and 1:9, respectively. Depending on cell disruption method along with solvents ratio, the total lipids content showed significant variations between 8.1% and 13.9 %. The highest percentage of extracted biomass was reached with a sample pretreated with microwave digestion using 90% of hexane and 10% of ethanol as solvents. Proteins content in microalgae was determined by two different methods, namely: Total Kejadahl Nitrogen (TKN), which further was converted to protein content, as well as Bradford method using Brilliant Blue G-250 dye. Obtained results, showed a good correlation between both methods with protein content being in the range of 39.8–47.1%. Characterization of neutral and acid saccharides from microalgae was conducted by phenol-sulfuric acid method at two wavelengths of 480 nm and 490 nm. The average concentration of neutral and acid saccharides under the optimal cultivation conditions was 19.5% and 26.1%, respectively. Subsequently, biomass residues are used as substrate for anaerobic digestion on the laboratory-scale. The methane concentration, which was measured on the daily bases, showed some variations for different samples after extraction steps but was in the range between 48% and 55%. CO₂ which is formed during the fermentation process and after the combustion in the Combined Heat and Power unit can potentially be used within the cultivation process as a carbon source for the photoautotrophic synthesis of biomass.

Keywords: bioeconomy, lipids, microalgae, proteins, saccharides

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Authors: Maha Bakakri, Rachid Tadili, Fatiha Lemmini

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Morocco is one of the few countries that have kept their traditional crafts, despite the competition of modern industry and its impact on manual labor. Therefore the optimization of energy consumption becomes an obligation and this is the purpose of this document. In this work we present some characteristics of the furnace studied, its operating principle and the experimental measurements of the evolutions of the temperatures inside and outside the walls of the furnace, values which will be used later in the calculation of its thermal losses. In order to determine the major source of the thermal losses of the furnace we have established the heat balance of the furnace. The energy consumed, the useful energy and the thermal losses through the walls and the chimney of the furnace are calculated thanks to the experimental measurements which we realized for several firings. The results show that the energy consumption of this type of furnace is very high and that the main source of energy loss is mainly due to the heat losses of the combustion gases that escape from the furnace by the chimney while the losses through the walls are relatively small. it have opted for energy recovery as a solution where we can recover some of the heat lost through the use of a heat exchanger system using a double tube introduced into the flue gas exhaust stack compartment. The study on the heat recovery system is presented and the heat balance inside the exchanger is established. In this paper we also present the numerical modeling of heat transfer by conduction through the walls of the furnace. A numerical model has been established based on the finite volume method and the double scan method. It makes it possible to determine the temperature profile of the furnace and thus to calculate the thermal losses of its walls and to deduce the thermal losses due to the combustion gases. Validation of the model is done using the experimental measurements carried out on the furnace. The results obtained in this work, relating to the energy consumed during the operation of the furnace are important and are part of the energy efficiency framework that has become a key element in global energy policies. It is the fastest and cheapest way to solve energy, environmental and economic security problems.

Keywords: energy cunsumption, energy recovery, modeling, energy eficiency

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Authors: Hellal Abdelkader, Chafaa Salah, Boudjemaa Fouzia

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A new, convenient, and high yielding procedure for the preparation of diethyl α-aminophosphonates in water via Kabachnik-Fields reaction by one-pot reaction of aromatic aldehydes, ortho-aminophenols, and dialkylphosphites in the presence of a low catalytic amount of citric, malic, tartaric, and oxalic acids as a natural, bi-functional, and highly stable catalyst is described, the obtained products were characterized by elemental analyses, molar conductance, magnetic susceptibility, FTIR, Uv-Vis spectral data, NMR-C, NMR-H, and NMR-P analyses.

Keywords: α-aminophosphonates, aminophenols, natural acids, aqueous media, Kabachnik-Fields reaction

Procedia PDF Downloads 326

Authors: Domenico Carmelo Mongelli

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The context of this research is that of the Italian reality, which, in order to adapt to the EU Directives that prohibit the production of internal combustion engines in favor of electric mobility from 2035, is extremely concerned about the significant loss of jobs resulting from the difficulty of the automotive industry in converting in such a short time and due to the reticence of potential buyers in the face of such an epochal change. The aim of the research is to evaluate for Italy the potential of the most valid alternative to this transition to electric: leaving the current production of diesel engines unchanged, no longer powered by gasoil, imported and responsible for greenhouse gas emissions, but powered entirely by a nationally produced and eco-sustainable fuel such as biodiesel. Today in Italy, the percentage of biodiesel mixed with gasoil for diesel engines is too low (around 10%); for this reason, this research aims to evaluate the functioning of current diesel engines powered 100% by biodiesel and the ability of the Italian production system to cope to this hypothesis. The research geographically identifies those abandoned lands in Italy, now out of the food market, which is best suited to an energy crop for the final production of biodiesel. The cultivation of oilseeds is identified, which for the Italian agro-industrial reality allows maximizing the agricultural and industrial yields of the transformation of the agricultural product into a final energy product and minimizing the production costs of the entire agro-industrial chain. To achieve this objective, specific databases are used, and energy and economic balances are prepared for the different agricultural product alternatives. Solutions are proposed and tested that allow the optimization of all production phases in both the agronomic and industrial phases. The biodiesel obtained from the most feasible of the alternatives examined is analyzed, and its compatibility with current diesel engines is identified, and from the evaluation of its thermo-fluid-dynamic properties, the engineering measures that allow the perfect functioning of current internal combustion engines are examined. The results deriving from experimental tests on the engine bench are evaluated to evaluate the performance of different engines fueled with biodiesel alone in terms of power, torque, specific consumption and useful thermal efficiency and compared with the performance of engines fueled with the current mixture of fuel on the market. The results deriving from experimental tests on the engine bench are evaluated to evaluate the polluting emissions of engines powered only by biodiesel and compared with current emissions. At this point, we proceed with the simulation of the total replacement of gasoil with biodiesel as a fuel for the current fleet of diesel vehicles in Italy, drawing the necessary conclusions in technological, energy, economic, and environmental terms and in terms of social and employment implications. The results allow us to evaluate the potential advantage of a total replacement of diesel fuel with biodiesel for powering road vehicles with diesel cycle internal combustion engines without significant changes to the current vehicle fleet and without requiring future changes to the automotive industry.

Keywords: biodiesel, economy, engines, environment

Procedia PDF Downloads 66

Authors: Lotanna Ezeonu, Jason P. Robbins, Ziyu Tang, Xiaofang Yang, Bruce E. Koel, Simon G. Podkolzin

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The interaction of organic molecules with metal surfaces is of interest in numerous technological applications, such as catalysis, bone replacement, and biosensors. Acetic acid is one of the main products of bio-oils produced from the pyrolysis of hemicellulosic feedstocks. However, their high oxygen content makes them unsuitable for use as fuels. Hydrodeoxygenation is a proven technique for catalytic deoxygenation of bio-oils. An understanding of the energetics and control of the bond-breaking sequences of biomass-derived oxygenates on metal surfaces will enable a guided optimization of existing catalysts and the development of more active/selective processes for biomass transformations to fuels. Such investigations have been carried out with the aid of ultrahigh vacuum and its concomitant techniques. The high catalytic activity of platinum in biomass-derived oxygenate transformations has sparked a lot of interest. We herein exploit infrared reflection absorption spectroscopy(IRAS), temperature-programmed desorption(TPD), and density functional theory(DFT) to study the adsorption and decomposition of acetic acid on a Pt(111) surface, which was then compared with Ni(111), a model non-noble metal. We found that acetic acid adsorbs molecularly on the Pt(111) surface, interacting through the lone pair of electrons of one oxygen atomat 90 K. At 140 K, the molecular form is still predominant, with some dissociative adsorption (in the form of acetate and hydrogen). Annealing to 193 K led to complete dehydrogenation of molecular acetic acid species leaving adsorbed acetate. At 440 K, decomposition of the acetate species occurs via decarbonylation and decarboxylation as evidenced by desorption peaks for H₂,CO, CO₂ and CHX fragments (x=1, 2) in theTPD.The assignments for the experimental IR peaks were made using visualization of the DFT-calculated vibrational modes. The results showed that acetate adsorbs in a bridged bidentate (μ²η²(O,O)) configuration. The coexistence of linear and bridge bonded CO was also predicted by the DFT results. Similar molecular acid adsorption energy was predicted in the case of Ni(111) whereas a significant difference was found for acetate adsorption.

Keywords: acetic acid, platinum, nickel, infared-absorption spectrocopy, temperature programmed desorption, density functional theory

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Authors: Aman Johri, Sidhant Sood, Pooja Suresh

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This paper suggests a new and more efficient method of atomization of fuel in a combustor nozzle of a high bypass turbofan engine, using ultrasonic vibrations. Since atomization of fuel just before the fuel spray is injected into the combustion chamber is an important and crucial aspect related to functioning of a propulsion system, the technology suggested by this paper and the experimental analysis on the system components eventually proves to assist in complete and rapid combustion of the fuel in the combustor module of the engine. Current propulsion systems use carburetors, atomization nozzles and apertures in air intake pipes for atomization. The idea of this paper is to deploy new age hybrid technology, namely the Ultrasound Field Effect (UFE) to effectively atomize fuel before it enters the combustion chamber, as a viable and effective method to increase efficiency and improve upon existing designs. The Ultrasound Field Effect is applied axially, on diametrically opposite ends of an atomizer tube that gloves onto the combustor nozzle, where the fuel enters and exits under a pre-defined pressure. The Ultrasound energy vibrates the fuel particles to a breakup frequency. At reaching this frequency, the fuel particles start disintegrating into smaller diameter particles perpendicular to the axis of application of the field from the parent boundary layer of fuel flow over the baseplate. These broken up fuel droplets then undergo swirling effect as per the original nozzle design, with a higher breakup ratio than before. A significant reduction of the size of fuel particles eventually results in an increment in the propulsive efficiency of the engine. Moreover, the Ultrasound atomizer operates within a control frequency such that effects of overheating and induced vibrations are least felt on the overall performance of the engine. The design of an electrical manifold for the multiple-nozzle system over a typical can-annular combustor is developed along with this study, such that the product can be installed and removed easily for maintenance and repairing, can allow for easy access for inspections and transmits least amount of vibrational energy to the surface of the combustor. Since near-field ultrasound is used, the vibrations are easily controlled, thereby successfully reducing vibrations on the outer shell of the combustor. Experimental analysis is carried out on the effect of ultrasonic vibrations on flowing jet turbine fuel using an ultrasound generator probe and results of an effective decrease in droplet size across a constant diameter, away from the boundary layer of flow is noted using visual aid by observing under ultraviolet light. The choice of material for the Ultrasound inducer tube and crystal along with the operating range of temperatures, pressures, and frequencies of the Ultrasound field effect are also studied in this paper, while taking into account the losses incurred due to constant vibrations and thermal loads on the tube surface.

Keywords: atomization, ultrasound field effect, titanium mesh, breakup frequency, parent boundary layer, baseplate, propulsive efficiency, jet turbine fuel, induced vibrations

Procedia PDF Downloads 233

Authors: Timur S. Zaripov, Artur K. Gilfanov, Sergei S. Sazhin, Steven M. Begg, Morgan R. Heikal

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The calculation of the concentration of inertial droplets in complex flows is encountered in the modelling of numerous engineering and environmental phenomena; for example, fuel droplets in internal combustion engines and airborne pollutant particles. The results of recent research, focused on the development of methods for calculating concentration and their implementation in the commercial CFD code, ANSYS Fluent, is presented here. The study is motivated by the investigation of the mixture preparation processes in internal combustion engines with direct injection of fuel sprays. Two methods are used in our analysis; the Fully Lagrangian method (also known as the Osiptsov method) and the Eulerian approach. The Osiptsov method predicts droplet concentrations along path lines by solving the equations for the components of the Jacobian of the Eulerian-Lagrangian transformation. This method significantly decreases the computational requirements as it does not require counting of large numbers of tracked droplets as in the case of the conventional Lagrangian approach. In the Eulerian approach the average droplet velocity is expressed as a function of the carrier phase velocity as an expansion over the droplet response time and transport equation can be solved in the Eulerian form. The advantage of the method is that droplet velocity can be found without solving additional partial differential equations for the droplet velocity field. The predictions from the two approaches were compared in the analysis of the problem of a dilute gas-droplet flow around an infinitely long, circular cylinder. The concentrations of inertial droplets, with Stokes numbers of 0.05, 0.1, 0.2, in steady-state and transient laminar flow conditions, were determined at various Reynolds numbers. In the steady-state case, flows with Reynolds numbers of 1, 10, and 100 were investigated. It has been shown that the results predicted using both methods are almost identical at small Reynolds and Stokes numbers. For larger values of these numbers (Stokes — 0.1, 0.2; Reynolds — 10, 100) the Eulerian approach predicted a wider spread in concentration in the perturbations caused by the cylinder that can be attributed to the averaged droplet velocity field. The transient droplet flow case was investigated for a Reynolds number of 200. Both methods predicted a high droplet concentration in the zones of high strain rate and low concentrations in zones of high vorticity. The maxima of droplet concentration predicted by the Osiptsov method was up to two orders of magnitude greater than that predicted by the Eulerian method; a significant variation for an approach widely used in engineering applications. Based on the results of these comparisons, the Osiptsov method has resulted in a more precise description of the local properties of the inertial droplet flow. The method has been applied to the analysis of the results of experimental observations of a liquid gasoline spray at representative fuel injection pressure conditions. The preliminary results show good qualitative agreement between the predictions of the model and experimental data.

Keywords: internal combustion engines, Eulerian approach, fully Lagrangian approach, gasoline fuel sprays, droplets and particle concentrations

Procedia PDF Downloads 254

Authors: Chitresh Prasad, Arvind Ramesh, Aditya Virkar, Karan Dholkaria, Vinayak Malhotra

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Solid Propellant Rocket is a rocket that utilises a combination of a solid Oxidizer and a solid Fuel. Success in Solid Rocket Motor design and development depends significantly on knowledge of burning rate behaviour of the selected solid propellant under all motor operating conditions and design limit conditions. Most Solid Motor Rockets consist of the Main Engine, along with multiple Boosters that provide an additional thrust to the space-bound vehicle. Though widely used, they have been eclipsed by Liquid Propellant Rockets, because of their better performance characteristics. The addition of a catalyst such as Iron Oxide, on the other hand, can drastically enhance the performance of a Solid Rocket. This scientific investigation tries to emulate the working of a Solid Rocket using Sparklers and Energized Candles, with a central Energized Candle acting as the Main Engine and surrounding Sparklers acting as the Booster. The Energized Candle is made of Paraffin Wax, with Magnesium filings embedded in it’s wick. The Sparkler is made up of 45% Barium Nitrate, 35% Iron, 9% Aluminium, 10% Dextrin and the remaining composition consists of Boric Acid. The Magnesium in the Energized Candle, and the combination of Iron and Aluminium in the Sparkler, act as catalysts and enhance the burn rates of both materials. This combustion of Metallized Propellants has an influence over the regression rate of the subject candle. The experimental parameters explored here are Separation Distance, Systematically varying Configuration and Layout Symmetry. The major performance parameter under observation is the Regression Rate of the Energized Candle. The rate of regression is significantly affected by the orientation and configuration of the sparklers, which usually act as heat sources for the energized candle. The Overall Efficiency of any engine is factorised by the thermal and propulsive efficiencies. Numerous efforts have been made to improve one or the other. This investigation focuses on the Orientation of Rocket Motor Design to maximize their Overall Efficiency. The primary objective is to analyse the Flame Spread Rate variations of the energized candle, which resembles the solid rocket propellant used in the first stage of rocket operation thereby affecting the Specific Impulse values in a Rocket, which in turn have a deciding impact on their Time of Flight. Another objective of this research venture is to determine the effectiveness of the key controlling parameters explored. This investigation also emulates the exhaust gas interactions of the Solid Rocket through concurrent ignition of the Energized Candle and Sparklers, and their behaviour is analysed. Modern space programmes intend to explore the universe outside our solar system. To accomplish these goals, it is necessary to design a launch vehicle which is capable of providing incessant propulsion along with better efficiency for vast durations. The main motivation of this study is to enhance Rocket performance and their Overall Efficiency through better designing and optimization techniques, which will play a crucial role in this human conquest for knowledge.

Keywords: design modifications, improving overall efficiency, metallized combustion, regression rate variations

Procedia PDF Downloads 171

Authors: L. M. López López, J. V. Montesdeoca Contreras, A. R. Cuji Fajardo, L. E. Garzón Muñoz, J. I. Fajardo Seminario

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In this article a new method of cleaning process of metal sheets for household appliances was developed, using low-pressure cold plasma. In this context, this research consist in analyze the results of metal sheets cleaning process using plasma and compare with pickling process to determinate the efficiency of each process and the level of contamination produced. Surface Cleaning was evaluated by measuring the contact angle with deionized water, diiodo methane and ethylene glycol, for the calculus of the surface free energy by means of the Fowkes theories and Wu. Showing that low-pressure cold plasma is very efficient both in cleaning process how in environment impact.

Keywords: efficient use of plasma, ecological impact of plasma, metal sheets cleaning means, plasma cleaning process.

Procedia PDF Downloads 344

Authors: Sandeep K. Saxena, N. Viswanadham, Ala’a H. Al-Muhtaseb

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In an attempt to facilitate effective conversion of biomass derived products into gasoline rich in aromatics and iso-paraffins, various zeolite catalysts with special features such as nano crystallite size and acidity has been synthesized and evaluated. The catalyst (NZ) exhibits highest gasoline yield of about 74wt% with aromatics and iso-paraffins as major components. The product measures Research Octane Number (RON) of about 95, which is desirable for the gasoline specifications. Moreover, considerable amount of the Liquefied Petroleum Gas (LPG) (15wt%) and light olefins (14wt%) are also formed as bi-product that adds value to the process. The study reveals the effective conversion of bio- ethanol to high-octane gasoline.

Keywords: biomass, ethanol, acetone, gasoline, zeolite

Procedia PDF Downloads 442