Search results for: water flow velocity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13022

Search results for: water flow velocity

11822 A Plan of Smart Management for Groundwater Resources

Authors: Jennifer Chen, Pei Y. Hsu, Yu W. Chen

Abstract:

Groundwater resources play a vital role in regional water supply because over 1/3 of total demand is satisfied by groundwater resources. Because over-pumpage might cause environmental impact such as land subsidence, a sustainable management of groundwater resource is required. In this study, a blueprint of smart management for groundwater resource is proposed and planned. The framework of the smart management can be divided into two major parts, hardware and software parts. First, an internet of groundwater (IoG) which is inspired by the internet of thing (IoT) is proposed to observe the migration of groundwater usage and the associated response, groundwater levels. Second, algorithms based on data mining and signal analysis are proposed to achieve the goal of providing highly efficient management of groundwater. The entire blueprint is a 4-year plan and this year is the first year. We have finished the installation of 50 flow meters and 17 observation wells. An underground hydrological model is proposed to determine the associated drawdown caused by the measured pumpages. Besides, an alternative to the flow meter is also proposed to decrease the installation cost of IoG. An accelerometer and 3G remote transmission are proposed to detect the on and off of groundwater pumpage.

Keywords: groundwater management, internet of groundwater, underground hydrological model, alternative of flow meter

Procedia PDF Downloads 379
11821 Mathematical Modelling and Parametric Study of Water Based Loop Heat Pipe for Ground Application

Authors: Shail N. Shah, K. K. Baraya, A. Madhusudan Achari

Abstract:

Loop Heat Pipe is a passive two-phase heat transfer device which can be used without any external power source to transfer heat from source to sink. The main aim of this paper is to have modelling of water-based LHP at varying heat loads. Through figures, how the fluid flow occurs within the loop has been explained. Energy Balance has been done in each section. IC (Iterative Convergence) scheme to find out the SSOT (Steady State Operating Temperature) has been developed. It is developed using Dev C++. To best of the author’s knowledge, hardly any detail is available in the open literature about how temperature distribution along the loop is to be evaluated. Results for water-based loop heat pipe is obtained and compared with open literature and error is found within 4%. Parametric study has been done to see the effect of different parameters on pressure drop and SSOT at varying heat loads.

Keywords: loop heat pipe, modelling of loop heat pipe, parametric study of loop heat pipe, functioning of loop heat pipe

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11820 Modeling of Sand Boil near the Danube River

Authors: Edina Koch, Károly Gombás, Márton Maller

Abstract:

The Little Plain is located along the Danube river, and this area is a “hotbed” of sand boil formation. This is due to the combination of a 100-250 m thick gravel layer beneath the Little Plain with a relatively thin blanket of poor soil spreading the gravel with variable thickness. Sand boils have a tradition and history in this area. It was possible to know which sand boil started and stopped working at what water level, and some of them even have names. The authors present a 2D finite element model of groundwater flow through a selected cross-section of the Danube river, which observed activation of piping phenomena during the 2013 flood event. Soil parametrization is based on a complex site investigation program conducted along the Danube River in the Little Plain.

Keywords: site characterization, groundwater flow, numerical modeling, sand boil

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11819 Evaluation of Geotechnical Parameters at Nubian Habitations in Kurkur Area, Aswan, Egypt

Authors: R. E. Fat-Helbary, A. A. Abdel-latief, M. S. Arfa, Alaa Mostafa

Abstract:

The Egyptian Government proposed a general plan, aiming at constructing new settlements for Nubian in south Aswan in different places around Nasser Lake, one of these settlements in Kurkur area. The Nubian habitations in Wadi Kurkur are located around 30 km southwest of Aswan City. This area are affecting by near distance earthquakes from Kalabsha faults system. The shallow seismic refraction technique was conducted at the study area, to evaluate the soil and rock material quality and geotechnical parameters, in addition to the detection of the subsurface ground model under the study area. The P and S-wave velocities were calculated. The surface layer has P-wave, velocity ranges from 900 m/sec to 1625 m/sec and S-wave velocity ranges from 650 m/sec to 1400 m/sec. On the other hand the bedrock has P-wave velocity ranges from 1300 m/sec to 1980 m/sec and S-wave velocity ranges from 1050 m/sec to1725 m/sec. Measuring Vp and Vs velocities together with bulk density are calculated and used to extract the mechanical properties and geotechnical parameters of the foundation material at the study area. Output of this study is very important for solving the problems, which associated with the construction of various civil engineering purposes, for land use planning and for earthquakes resistant structure design.

Keywords: shallow seismic refraction technique, Kurkur area, p and s-wave velocities, geotechnical parameters, bulk density, Kalabsha faults

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11818 A Theoretical Model for a Humidification Dehumidification (HD) Solar Desalination Unit

Authors: Yasser El-Henawy, M. Abd El-Kader, Gamal H. Moustafa

Abstract:

A theoretical study of a humidification dehumidification solar desalination unit has been carried out to increase understanding the effect of weather conditions on the unit productivity. A humidification-dehumidification (HD) solar desalination unit has been designed to provide fresh water for population in remote arid areas. It consists of solar water collector and air collector; to provide the hot water and air to the desalination chamber. The desalination chamber is divided into humidification and dehumidification towers. The circulation of air between the two towers is maintained by the forced convection. A mathematical model has been formulated, in which the thermodynamic relations were used to study the flow, heat and mass transfer inside the humidifier and dehumidifier. The present technique is performed in order to increase the unit performance. Heat and mass balance has been done and a set of governing equations has been solved using the finite difference technique. The unit productivity has been calculated along the working day during the summer and winter sessions and has compared with the available experimental results. The average accumulative productivity of the system in winter has been ranged between 2.5 to 4 kg/m2.day, while the average summer productivity has been found between 8 to 12 kg/m2 day.

Keywords: solar desalination, solar collector, humidification and dehumidification, simulation, finite difference, water productivity

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11817 Study on the Wave Dissipation Performance of Double-Cylinder and Double-Plate Floating Breakwater

Authors: Liu Bijin

Abstract:

Floating breakwaters have several advantages, including being environmentally friendly, easy to construct, and cost-effective regardless of water depth. They have a broad range of applications in coastal engineering. However, they face significant challenges due to the unstable effect of wave dissipation, structural vulnerability, and high mooring system requirements. This paper investigates the wave dissipation performance of a floating breakwater structure. The structure consists of double cylinders, double vertical plates, and horizontal connecting plates. The investigation is carried out using physical model tests and numerical simulation methods based on STAR-CCM+. This paper discusses the impact of wave elements, relative vertical plate heights, and relative horizontal connecting plate widths on the wave dissipation performance of the double-cylinder, double-plate floating breakwater (DCDPFB). The study also analyses the changes in local vorticity and velocity fields around the DCDPFB to determine the optimal structural dimensions. The study found that the relative width of the horizontal connecting plate, the relative height of the vertical plate, and the size of the semi-cylinder are the key factors affecting the wave dissipation performance of the DCDPFB. The transmittance coefficient is minimally affected by the wave height and the depth of water entry. The local vortex and velocity field formed around the DCDPFB are important factors for dissipating wave energy. The test section of the DCDPFB, constructed according to the relative optimal structural dimensions, showed good wave dissipation performance during offshore prototype tests. The test section of DCDPFB, constructed with optimal structural dimensions, exhibits excellent wave dissipation performance in offshore prototype tests.

Keywords: floating breakwater, wave dissipation performance, transmittance coefficient, model test

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11816 Experimental and Computational Investigation of Flow Field and Thermal Behavior of a Mechanical Seal

Authors: Hossein Shokouhmand, Masoomeh Shadab, Rohallah Torabi

Abstract:

Turbulent flow inside the seal chamber of a pump operating at nearly high Reynolds number is investigated. A comparison of a 3-D computational model for flow and thermal analysis of a mechanical seal with experimental thermal results is presented. The computational model adequately predicts the flow field in the seal chamber and thermal characteristics with the rotating and stationary rings and the twister flow around the seal parts by solving N-S and energy equations in ANSYS-CFX software. The Reynolds stress model (RSM) is applied as a turbulence model for this purpose. Experimental work is discussed which quantifies the temperature of five different points of the working fluid in chamber, mass flow at inlet and the fluid pressure at inlet and outlet. Experimental measurements are combined with computational modeling to obtain local and average heat transfer characteristics. Numerical results of three cases including different flush rates are reported.

Keywords: mechanical seal, CFD_CFX, reynolds stress model, flow field, heat transfer analysis, stream line, heat transfer coefficient, heat flux, nusselt

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11815 Energy Saving in Handling the Air-Conditioning Latent-Load Using a Liquid Desiccant Air Conditioner: Parametric Experimental Analysis

Authors: Mustafa Jaradat

Abstract:

Reasonable energy saving for dehumidification is feasible with the use of desiccants. Desiccants are able to lower the humidity content in the air irrespective of the dew point temperature. In this paper, a tube bundle liquid desiccant air conditioner was experimentally designed and evaluated using lithium chloride as a desiccant. Several experiments were conducted to evaluate the influence of the inlet parameters on the dehumidifier performance. The results show a reduction in the relative humidity in the range of 17 to 46%, and the change in the humidity ratio was between 1.5 to 4.7 g/kg, depending on the inlet conditions. A water removal rate in the range between 0.54 and 1.67 kg/h was observed. The effects of air relative humidity and the desiccant flow rate on the dehumidifier’s performance were investigated. It was found that the moisture removal rate remarkably increased with increasing desiccant flow rate and air inlet humidity ratio. The dehumidifier effectiveness increased sharply with increasing desiccant flow rate. Also, it was found that the dehumidifier effectiveness slightly decreased with air humidity ratio.

Keywords: air conditioning, dehumidification, desiccant, lithium chloride, tube bundle

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11814 Determination of Optimum Water Consumptive Using Deficit Irrigation Model for Barely: A Case Study in Arak, Iran

Authors: Mohsen Najarchi

Abstract:

This research was carried out in five fields (5-15 hectares) in Arak located in center of Iran, to determine optimum level of water consumed for Barely in four stages growth (vegetative, yield formation, flowering, and ripening). Actual evapotranspiration was calculated using measured water requirement in the fields. Five levels of water requirement equal to 50, 60, 70, 80, and 90 percents formed the treatments. To determine the optimum level of water requirement linear programming was used. The study showed 60 percent water requirement (40 percent deficit irrigation) has been the optimum level of irrigation for winter wheat in four stages of growth. Comparison between all of the treatments indicated above with normal condition (100% water requirement) shows increasing in water use efficiency. Although 40% deficit irrigation treatment lead to decrease of 38% in yield, net benefit was increasing in 11.37%. Furthermore, in comparison with normal condition, 70% of water requirement increased water use efficiency as 30%.

Keywords: optimum, deficit irrigation, water use efficiency, evapotranspiration

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11813 An Experimental Study of the Influence of Flow Rate on Formation Damage at Different pH

Authors: Khabat M. Ahmad

Abstract:

This experiment focuses on the reduction of permeability (formation damage) as a result of fines migration by changing pH and flow rate on core plugs selected from sandstone reservoir of Pannonian basin (Upper Miocene, East Hungary). The main objective of coreflooding experiments was to investigate the influence of both high and low pH fluids and the flow rate on stability of clay minerals. The selected core samples were examined by X-ray powder diffraction (XRD) for bulk mineralogical and clay mineral composition. The shape, position, distribution and type of clay minerals within the core samples were diagnosed by scanning electron microscopy and energy dispersive spectroscopy (SEM- EDS). The basic petrophysical properties such as porosity and initial permeability were determined prior to experiments. The special core analysis (influence of pH and flow rate) on permeability reduction was examined through a series of laboratory coreflooding experiments, testing for acidic (3) and alkaline (11) solutions at different flow rates (50, 100 and 200 ml/h). Permeability in continuously reduced for pH 11 to more than 50 % of initial permeability. However, at pH 3 after a slow decrease, a significant increase is observed, to more than 40 % of initial permeability. The variation is also influenced by flow rate.

Keywords: flow rate, pH, permeability, fine migration, formation damage, XRD, SEM- EDS

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11812 The Effect of Magnetic Water on the Growth of Radish Cherry

Authors: Elisha Didam Markus, Thapelo Maqame

Abstract:

This paper focuses on studying the effects of magnetism on water and their impact to plant growth. Magnetic fields are known to induce higher rate of biochemical reaction and therefore can be used for growth related reactions in plants. For the purpose of this study, two 2 litres bottles were taken, one with two opposite poles magnets (500 mT) one on top and one at the bottom of the bottle. Another bottle was not altered in any way (used as control). Each bottle contained tap water stored up for 24 hours. Plants planted into different pots were watered using water from these bottles. Four pots with soil and manure equally mixed were used and equal volume of radish berry seeds were planted. Two pots were watered with magnetised water and the other two with normal tap water. The developments of plants were monitored in terms of their lengths for a period of 21 days. After 21 days, the lengths of plants watered with magnetised water were found to be 5.6% longer than those watered with tap water.

Keywords: magnetised water, radish berry, growth percentage, magnetic fields

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11811 Investigation of Turbulent Flow in a Bubble Column Photobioreactor and Consequent Effects on Microalgae Cultivation Using Computational Fluid Dynamic Simulation

Authors: Geetanjali Yadav, Arpit Mishra, Parthsarathi Ghosh, Ramkrishna Sen

Abstract:

The world is facing problems of increasing global CO2 emissions, climate change and fuel crisis. Therefore, several renewable and sustainable energy alternatives should be investigated to replace non-renewable fuels in future. Algae presents itself a versatile feedstock for the production of variety of fuels (biodiesel, bioethanol, bio-hydrogen etc.) and high value compounds for food, fodder, cosmetics and pharmaceuticals. Microalgae are simple microorganisms that require water, light, CO2 and nutrients for growth by the process of photosynthesis and can grow in extreme environments, utilize waste gas (flue gas) and waste waters. Mixing, however, is a crucial parameter within the culture system for the uniform distribution of light, nutrients and gaseous exchange in addition to preventing settling/sedimentation, creation of dark zones etc. The overarching goal of the present study is to improve photobioreactor (PBR) design for enhancing dissolution of CO2 from ambient air (0.039%, v/v), pure CO2 and coal-fired flue gas (10 ± 2%) into microalgal PBRs. Computational fluid dynamics (CFD), a state-of-the-art technique has been used to solve partial differential equations with turbulence closure which represents the dynamics of fluid in a photobioreactor. In this paper, the hydrodynamic performance of the PBR has been characterized and compared with that of the conventional bubble column PBR using CFD. Parameters such as flow rate (Q), mean velocity (u), mean turbulent kinetic energy (TKE) were characterized for each experiment that was tested across different aeration schemes. The results showed that the modified PBR design had superior liquid circulation properties and gas-liquid transfer that resulted in creation of uniform environment inside PBR as compared to conventional bubble column PBR. The CFD technique has shown to be promising to successfully design and paves path for a future research in order to develop PBRs which can be commercially available for scale-up microalgal production.

Keywords: computational fluid dynamics, microalgae, bubble column photbioreactor, flue gas, simulation

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11810 The Relation of Water Intake with Level of Knowledge Related to Water Intake in Workers of Food Production Unit, Nutrition Installation at Puspa Hospital, Jakarta

Authors: Siti Rahmah Fitrianti, Mela Milani

Abstract:

Inadequate of water intake has negative effects on the health of the body, which can cause kidney failure and death. One of the factors that can affect someone intake of water is level of knowledge about the importance of water intake itself. A good knowledge of the daily water intake can increase the awareness of daily needed of water intake. Therefore, researchers initiated a study on the relationship of water intake to the level of knowledge related with water intake in food workers, at “Puspa” Hospital. Type of this research is quantitative research with cross-sectional approach. The research data was collected by measuring the independent and dependent variable at a time. This study took place in the food production unit of Nutrition Installation in "Puspa" Hospital, Jakarta in October 2016. The population target in this study were workers in food production unit aged 30-64 years. The instrument was a questionnaire question regarding water intake and 24 hours food recall. The result is 78.6% of respondents have less knowledge about the importance of water intake. Meanwhile, as many as 85.7% of respondents have adequate water intake. Tested by Chi-Square test, showed that no significant relationship between water intake with the level of knowledge related to water intake in workers of food production unit. Adequate intake of water in food workers commonly may be not caused by the level of knowledge related to water intake, but it may be cause of work environment factor which has a high temperature.

Keywords: food production unit, food workers, level of knowledge, water intake

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11809 A Study on Energy Efficiency of Vertical Water Treatment System with DC Power Supply

Authors: Young-Kwan Choi, Gang-Wook Shin, Sung-Taek Hong

Abstract:

Water supply system consumes large amount of power load during water treatment and transportation of purified water. Many energy conserving high efficiency materials such as DC motor and LED light have recently been introduced to water supply system for energy conservation. This paper performed empirical analysis on BLDC, AC motors, and comparatively analyzed the change in power according to DC power supply ratio in order to conserve energy of a next-generation water treatment system called vertical water treatment system. In addition, a DC distribution system linked with photovoltaic generation was simulated to analyze the energy conserving effect of DC load.

Keywords: vertical water treatment system, DC power supply, energy efficiency, BLDC

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11808 Infection Risk of Fecal Coliform Contamination in Drinking Water Sources of Urban Slum Dwellers: Application of Quantitative Microbiological Risk Assessment

Authors: Sri Yusnita Irda Sari, Deni Kurniadi Sunjaya, Ardini Saptaningsih Raksanagara

Abstract:

Water is one of the fundamental basic needs for human life, particularly drinking water sources. Although water quality is getting better, fecal-contamination of water is still found around the world, especially in the slum area of mid-low income countries. Drinking water source contamination in urban slum dwellers increases the risk of water borne diseases. Low level of sanitation and poor drinking water supply known as risk factors for diarrhea, moreover bacteria-contaminated drinking water source is the main cause of diarrhea in developing countries. This study aimed to assess risk infection due to Fecal Coliform contamination in various drinking water sources in urban area by applying Quantitative Microbiological Risk Assessment (QMRA). A Cross-sectional survey was conducted in a period of August to October 2015. Water samples were taken by simple random sampling from households in Cikapundung river basin which was one of urban slum area in the center of Bandung city, Indonesia. About 379 water samples from 199 households and 15 common wells were tested. Half of the households used treated drinking water from water gallon mostly refill water gallon which was produced in drinking water refill station. Others used raw water sources which need treatment before consume as drinking water such as tap water, borehole, dug well and spring water source. Annual risk to get infection due to Fecal Coliform contamination from highest to lowest risk was dug well (1127.9 x 10-5), spring water (49.7 x 10-5), borehole (1.383 x 10-5) and tap water (1.121 x 10-5). Annual risk infection of refill drinking water was 1.577 x 10-5 which is comparable to borehole and tap water. Household water treatment and storage to make raw water sources drinkable is essential to prevent risk of water borne diseases. Strong regulation and intense monitoring of refill water gallon quality should be prioritized by the government; moreover, distribution of tap water should be more accessible and affordable especially in urban slum area.

Keywords: drinking water, quantitative microbiological risk assessment, slum, urban

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11807 Thermal Performance of an Air-Water Heat Exchanger (AWHE) Operating in Groundwater and Hot-Humid Climate

Authors: César Ramírez-Dolores, Jorge Wong-Loya, Jorge Andaverde, Caleb Becerra

Abstract:

Low-depth geothermal energy can take advantage of the use of the subsoil as an air conditioning technique, being used as a passive system or coupled to an active cooling and/or heating system. This source of air conditioning is possible because at a depth less than 10 meters, the subsoil temperature is practically homogeneous and tends to be constant regardless of the climatic conditions on the surface. The effect of temperature fluctuations on the soil surface decreases as depth increases due to the thermal inertia of the soil, causing temperature stability; this effect presents several advantages in the context of sustainable energy use. In the present work, the thermal behavior of a horizontal Air-Water Heat Exchanger (AWHE) is evaluated, and the thermal effectiveness and temperature of the air at the outlet of the prototype immersed in groundwater is experimentally determined. The thermohydraulic aspects of the heat exchanger were evaluated using the Number of Transfer Units-Efficiency (NTU-ε) method under conditions of groundwater flow in a coastal region of sandy soil (southeastern Mexico) and air flow induced by a blower, the system was constructed of polyvinyl chloride (PVC) and sensors were placed in both the exchanger and the water to record temperature changes. The results of this study indicate that when the exchanger operates in groundwater, it shows high thermal gains allowing better heat transfer, therefore, it significantly reduces the air temperature at the outlet of the system, which increases the thermal effectiveness of the system in values > 80%, this passive technique is relevant for building cooling applications and could represent a significant development in terms of thermal comfort for hot locations in emerging economy countries.

Keywords: convection, earth, geothermal energy, thermal comfort

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11806 A Dynamic Column Adsorption Study of Methyl Blue on Synthesis onto Synthesized Chitosan Immobilized Sawdust Cellulose Nanocrystals

Authors: Opeyemi A. Oyewo, Seshibe Makgato

Abstract:

This paper presents the synthesis, characterization, and application of pelletized chitosan immobilized sawdust cellulose nanocrystals (PCCN) in a fixed-bed column for the continuous adsorption of methyl blue (MB) from water. The product was characterized using FT-IR, XRD, and SEM analysis. Microstructural examination revealed that the pellets are porous and spherical. XRD examination revealed phases that can be attributed to the presence of chitosan in PCCN. The effects of starting concentration, bed depth, and flow rate on synthetic water were explored. To identify MB breakthrough behaviour, performance indices such as bed volume, adsorbent exhaustion rate, and service time were investigated. Furthermore, the breakthrough data were incorporated into both the Thomas and Bohart-Adams models. The Thomas model was suitable for describing MB breakthrough curves. However, more research with diverse water matrices may be required to assess the resilience of PCCN.

Keywords: adsorption, dynamic, methyl blue, pelletization

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11805 Modification of Polyolefin Membrane Using Supercritical Carbon Dioxide for Redox Flow Batteries

Authors: Vadim V. Zefirov, Victor E. Sizov, Marina A. Pigaleva, Igor V. Elmanovich, Mikhail S. Kondratenko, Marat O. Gallyamov

Abstract:

This work presents a novel method for treating porous hydrophobic polyolefin membranes using supercritical carbon dioxide that allows usage of the modified membrane in redox flow batteries with an aqueous electrolyte. Polyolefin membranes are well known and widely used, however, they cannot be used as separators in redox flow batteries with an aqueous electrolyte since they have insufficient wettability, and therefore do not provide sufficient proton conductivity. The main aim of the presented work was the development of hydrophilic composites based on cheap membranes and precursors. Supercritical fluid was used as a medium for the deposition of the hydrophilic phase on the hydrophobic surface of the membrane. Due to the absence of negative capillary effects in a supercritical medium, a homogeneous composite is obtained as a result of synthesis. The in-situ synthesized silicon oxide nanoparticles and the chitosan polymer layer act as the hydrophilic phase and not only increase the affinity of the membrane towards the electrolyte, but also reduce the pore size of the polymer matrix, which positively affects the ion selectivity of the membrane. The composite material obtained as a result of synthesis has enhanced hydrophilic properties and is capable of providing proton conductivity in redox flow batteries. The morphology of the obtained composites was characterized by electron microscopy. To analyze the phase composition, infrared spectroscopy was used. The hydrophilic properties were studied by water contact angle measurements. In addition, the proton conductivity and ion selectivity of the obtained samples were studied, and tests in real redox flow batteries were performed. As a result, modified membrane was characterised in detail and moreover it was shown that modified cheap polyolefin membranes have pronounced proton conductivity and high ion selectivity, so their performance in a real redox flow battery approaches expensive commercial analogues, reaching 70% of energy efficiency.

Keywords: carbon dioxide, chitosan, polymer membrane, redox flow batteries, silica nanoparticles, supercritical fluid

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11804 Evaluation of Sloshing in Process Equipment for Floating Cryogenic Application

Authors: Bo Jin

Abstract:

A variety of process equipment having flow in and out is widely used in industrial land-based cryogenic facilities. In some of this equipment, such as vapor-liquid separator, a liquid level is established during the steady operation. As the implementation of such industrial processes extends to off-shore floating facilities, it is important to investigate the effect of sea motion on the process equipment partially filled with liquid. One important aspect to consider is the occurrence of sloshing therein. The flow characteristics are different from the classical study of sloshing, where the fluid is enclosed inside a vessel (e.g., storage tank) with no flow in or out. Liquid inside process equipment continuously flows in and out of the system. To understand this key difference, a Computational Fluid Dynamics (CFD) model is developed to simulate the liquid motion inside a partially filled cylinder with and without continuous flow in and out. For a partially filled vertical cylinder without any continuous flow in and out, the CFD model is found to be able to capture the well-known sloshing behavior documented in the literature. For the cylinder with a continuous steady flow in and out, the CFD simulation results demonstrate that the continuous flow suppresses sloshing. Given typical cryogenic fluid has very low viscosity, an analysis based on potential flow theory is developed to explain why flow into and out of the cylinder changes the natural frequency of the system and thereby suppresses sloshing. This analysis further validates the CFD results.

Keywords: computational fluid dynamics, CFD, cryogenic process equipment, off-shore floating processes, sloshing

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11803 Contamination of the Groundwater by the Flow of the Discharge in Khouribga City (Morocco) and the Danger It Presents to the Health of the Surrounding Population.

Authors: Najih Amina

Abstract:

Our study focuses on monitoring the spatial evolution of a number of physico-chemical parameters of wells waters located at different distances from the discharge of the city of Khouribga (S0 upstream station, S1, S2 et S3 are respectively located at 5.5, 7.5, 11 Km away from solid waste discharge of the city). The absence of a source of drinking water in this region involves the population to feeding on its groundwater wells. Through the results, we note that most of the analyzed parameters exceed the potable water standards from S1. At this source of water, we find that the conductivity (1290 μmScm-1; Standard 1000 μmScm-1), Total Hardness TH (67.2°F/ Standard 50° F), Ca2 + (146 mg l-1 standard 60 mg l-1), Cl- (369 mg l-1 standard 150 mg l-1), NaCl (609 mgl-1), Methyl orange alakanity “M. alk” (280 mg l-1) greatly exceed the drinking water standards. By following these parameters, it is obvious that some values have decreased in the downstream stations, while others become important. We find that the conductivity is always higher than 950 μmScm-1; the TH registers 72°F in S3; Ca 2+ is in the range of 153 mg l-1 in S3, Cl- and NaCl- reached 426 mg l-1 and 702 mg l-1 respectively in S2, M alk becomes higher and reaches 430 to 350 in S3. At the wells S2, we found that the nitrites are well beyond the standard 1.05 mg l-1. Whereas, at the control station S0, the values are lower or at the limit of drinking water standards: conductivity (452 μmScm-1), TH (34 F°), Ca2+ (68 mg l-1), Cl- (157 mg l-1), NaCl- (258 mg l-1), M alk (220 mg l-1). Thus, the diagnosis reveals the presence of a high pollution caused by the leachates of the household waste discharge and by the effluents of the sewage waste water plant (SWWP). The phenomenon of the water hardness could, also, be generated by the processes of erosion, leaching and soil infiltration in the region (phosphate layers, intercalated layers of marl and limestone), phenomenons also caused by the acidity due to this surrounding pollution. The source S1 is the nearest surrounding site of the discharge and the most affected by the phenomenon of pollution, especially, it is near to a superficial water source S’1 polluted by the effluents coming from the sewage waste water plant of the city. In the light of these data, we can deduce that the consumption of this water from S1 does not conform the standards of drinking waters, and could affect the human health.

Keywords: physico-chemical parameters, ground water wells, infiltration, leaching, pollution, leachate discharge effluent SWWP, human health.

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11802 Analysis of the Detachment of Water Droplets from a Porous Fibrous Surface

Authors: Ibrahim Rassoul, E-K. Si Ahmed

Abstract:

The growth, deformation, and detachment of fluid droplets adherent to solid substrates is a problem of fundamental interest with numerous practical applications. Specific interest in this proposal is the problem of a droplet on a fibrous, hydrophobic substrate subjected to body or external forces (gravity, convection). The past decade has seen tremendous advances in proton exchange membrane fuel cell (PEMFC) technology. However, there remain many challenges to bring commercially viable stationary PEMFC products to the market. PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On the one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause 'flooding' (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The aim of this work is to investigate the stability of a liquid water droplet emerging form a GDL pore, to gain fundamental insight into the instability process leading to detachment. The approach will combine analytical and numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, water droplet, gas diffusion layer, contact angle, surface tension

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11801 A Novel NRIS Index to Evaluate Brain Activity in Prefrontal Regions While Listening to First and Second Languages for Long Time Periods

Authors: Kensho Takahashi, Ko Watanabe, Takashi Kaburagi, Hiroshi Tanaka, Kajiro Watanabe, Yosuke Kurihara

Abstract:

Near-infrared spectroscopy (NIRS) has been widely used as a non-invasive method to measure brain activity, but it is corrupted by baseline drift noise. Here we present a method to measure regional cerebral blood flow as a derivative of NIRS output. We investigate whether, when listening to languages, blood flow can reasonably localize and represent regional brain activity or not. The prefrontal blood flow distribution pattern when advanced second-language listeners listened to a second language (L2) was most similar to that when listening to their first language (L1) among the patterns of mean and standard deviation. In experiments with 25 healthy subjects, the maximum blood flow was localized to the left BA46 of advanced listeners. The blood flow presented is robust to baseline drift and stably localizes regional brain activity.

Keywords: NIRS, oxy-hemoglobin, baseline drift, blood flow, working memory, BA46, first language, second language

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11800 Approach to Study the Workability of Concrete with the Fractal Model

Authors: Achouri Fatima, Chouicha Kaddour

Abstract:

The main parameters affecting the workability are the water content, particle size, and the total surface of the grains, as long as the mixing water begins by wetting the surface of the grains and then fills the voids between the grains to form entrapped water, the quantity of water remaining is called free water. The aim is to undertake a fractal approach through the relationship between the concrete formulation parameters and workability, to develop this approach a series of concrete taken from the literature was investigated by varying formulation parameters such as G / S, the quantity of cement C and the quantity of mixing water E. We also call on other model as the model for the thickness of the water layer and model of the thickness of the paste layer to judge their relevance, hence the following results : the relevance of the model of the thickness of the water layer is considered relevant when there is a variation in the water quantity, the model of the thickness of the layer of the paste is only applicable if we consider that the paste is made with the grain value Dmax = 2.85: value from which we see a stable model.

Keywords: concrete, fractal method, paste thickness, water thickness, workability

Procedia PDF Downloads 379
11799 A Model for Predicting Organic Compounds Concentration Change in Water Associated with Horizontal Hydraulic Fracturing

Authors: Ma Lanting, S. Eguilior, A. Hurtado, Juan F. Llamas Borrajo

Abstract:

Horizontal hydraulic fracturing is a technology to increase natural gas flow and improve productivity in the low permeability formation. During this drilling operation tons of flowback and produced water which contains many organic compounds return to the surface with a potential risk of influencing the surrounding environment and human health. A mathematical model is urgently needed to represent organic compounds in water transportation process behavior and the concentration change with time throughout the hydraulic fracturing operation life cycle. A comprehensive model combined Organic Matter Transport Dynamic Model with Two-Compartment First-order Model Constant (TFRC) Model has been established to quantify the organic compounds concentration. This algorithm model is composed of two transportation parts based on time factor. For the fast part, the curve fitting technique is applied using flowback water data from the Marcellus shale gas site fracturing and the coefficients of determination (R2) from all analyzed compounds demonstrate a high experimental feasibility of this numerical model. Furthermore, along a decade of drilling the concentration ratio curves have been estimated by the slow part of this model. The result shows that the larger value of Koc in chemicals, the later maximum concentration in water will reach, as well as all the maximum concentrations percentage would reach up to 90% of initial concentration from shale formation within a long sufficient period.

Keywords: model, shale gas, concentration, organic compounds

Procedia PDF Downloads 226
11798 Secured Power flow Algorithm Including Economic Dispatch with GSDF Matrix Using LabVIEW

Authors: Slimane Souag, Amel Graa, Farid Benhamida

Abstract:

In this paper we present a new method for solving the secured power flow problem by the economic dispatch using DC power flow method and Generation Shift Distribution Factor (GSDF), in this work we create a graphical interface in LabVIEW as a virtual instrument. Hence the dc power flow reduces the power flow problem to a set of linear equations, which make the iterative calculation very fast and the GSFD matrix present the effects of single and multiple generator MW change on the transmission line. The effectiveness of the method developed is identified through its application to an IEEE-14 bus test system. The calculation results show excellent performance of the proposed method, in regard to computation time and quality of results.

Keywords: electrical power system security, economic dispatch, sensitivity matrix, labview

Procedia PDF Downloads 489
11797 A Sustainable and Low-Cost Filter to Treat Pesticides in Water

Authors: T. Abbas, J. McEvoy, E. Khan

Abstract:

Pesticide contamination in water supply is a common environmental problem in rural agricultural communities. Advanced water treatment processes such as membrane filtration and adsorption on activated carbon only remove pesticides from water without degrading them into less toxic/easily degradable compounds leaving behind contaminated brine and activated carbon that need to be managed. Rural communities which normally cannot afford expensive water treatment technologies need an economical and sustainable filter which not only treats pesticides from water but also degrades them into benign products. In this study, iron turning waste experimented as potential point-of-use filtration media for the removal/degradation of a mixture of six chlorinated pesticides (lindane, heptachlor, endosulfan, dieldrin, endrin, and DDT) in water. As a common and traditional medium for water filtration, sand was also tested along with iron turning waste. Iron turning waste was characterized using scanning electron microscopy and energy dispersive X-Ray analyzer. Four glass columns with different filter media layer configurations were set up: (1) only sand, (2) only iron turning, (3) sand and iron turning (two separate layers), and (4) sand, iron turning and sand (three separate layers). The initial pesticide concentration and flow rate were 2 μg/L and 10 mL/min. Results indicate that sand filtration was effective only for the removal of DDT (100%) and endosulfan (94-96%). Iron turning filtration column effectively removed endosulfan, endrin, and dieldrin (85-95%) whereas the lindane and DDT removal were 79-85% and 39-56%, respectively. The removal efficiencies for heptachlor, endosulfan, endrin, dieldrin, and DDT were 90-100% when sand and iron turning waste (two separate layers) were used. However, better removal efficiencies (93-100%) for five out of six pesticides were achieved, when sand, iron turning and sand (three separate layers) were used as filtration media. Moreover, the effects of water pH, amounts of media, and minerals present in water such as magnesium, sodium, calcium, and nitrate on the removal of pesticides were examined. Results demonstrate that iron turning waste efficiently removed all the pesticides under studied parameters. Also, it completely de-chlorinated all the pesticides studied and based on the detection of by-products, the degradation mechanisms for all six pesticides were proposed.

Keywords: pesticide contamination, rural communities, iron turning waste, filtration

Procedia PDF Downloads 255
11796 Comparison of On-Site Stormwater Detention Real Performance and Theoretical Simulations

Authors: Pedro P. Drumond, Priscilla M. Moura, Marcia M. L. P. Coelho

Abstract:

The purpose of On-site Stormwater Detention (OSD) system is to promote the detention of addition stormwater runoff caused by impervious areas, in order to maintain the peak flow the same as the pre-urbanization condition. In recent decades, these systems have been built in many cities around the world. However, its real efficiency continues to be unknown due to the lack of research, especially with regard to monitoring its real performance. Thus, this study aims to compare the water level monitoring data of an OSD built in Belo Horizonte/Brazil with the results of theoretical methods simulations, usually adopted in OSD design. There were made two theoretical simulations, one using the Rational Method and Modified Puls method and another using the Soil Conservation Service (SCS) method and Modified Puls method. The monitoring data were obtained with a water level sensor, installed inside the reservoir and connected to a data logger. The comparison of OSD performance was made for 48 rainfall events recorded from April/2015 to March/2017. The comparison of maximum water levels in the OSD showed that the results of the simulations with Rational/Puls and SCS/Puls methods were, on average 33% and 73%, respectively, lower than those monitored. The Rational/Puls results were significantly higher than the SCS/Puls results, only in the events with greater frequency. In the events with average recurrence interval of 5, 10 and 200 years, the maximum water heights were similar in both simulations. Also, the results showed that the duration of rainfall events was close to the duration of monitored hydrograph. The rising time and recession time of the hydrographs calculated with the Rational Method represented better the monitored hydrograph than SCS Method. The comparison indicates that the real discharge coefficient value could be higher than 0.61, adopted in Puls simulations. New researches evaluating OSD real performance should be developed. In order to verify the peak flow damping efficiency and the value of the discharge coefficient is necessary to monitor the inflow and outflow of an OSD, in addition to monitor the water level inside it.

Keywords: best management practices, on-site stormwater detention, source control, urban drainage

Procedia PDF Downloads 188
11795 Preliminary Study on Using of Thermal Energy from Effluent Water for the SBR Process of RO

Authors: Gyeong-Sung Kim, In-soo Ahn, Yong Cho

Abstract:

SBR (Sequencing Batch Reactor) process is usually applied to membrane water treatment plants to treat its concentrated wastewater. The role of SBR process is to remove COD (Chemical Oxygen Demand) and NH3 from wastewater before discharging it outside of the water treatment plant using microorganism. Microorganism’s nitrification capability is influenced by water temperature because the nitrification rate of the concentrated wastewater becomes ‘zero’ as water temperature approach 0℃. Heating system is necessary to operate SBR in winter season even though the operating cost increase sharply. The operating cost of SBR at ‘D’ RO water treatment plant in Korea was 51.8 times higher in winter (October to March) compare to summer (April to September) season in 2014. Otherwise the effluent water temperature maintained around 8℃ constantly in winter. This study focuses on application heat pump system to recover the thermal energy from the effluent water of ‘D’ RO plant so that the operating cost will be reduced.

Keywords: water treatment, water thermal energy, energy saving, RO, SBR

Procedia PDF Downloads 516
11794 Aerodynamic Design Optimization of Ferrari F430 Flying Car with Enhanced Takeoff Performance

Authors: E. Manikandan, C. Chilambarasan, M. Sulthan Ariff Rahman, S. Kanagaraj, Abhimanyu Pugazhandhi, V. R. Sanal Kumar

Abstract:

The designer of any flying car has the major concern on the creation of upward force with low takeoff velocity, with minimum drag, coupled with better stability and control warranting its overall high performance both in road and air. In this paper, 3D numerical simulations of external flow of a Ferrari F430 fitted with different NACA series rectangular wings have been carried out for finding the best aerodynamic design option in road and air. The principle that allows a car to rise off the ground by creating lift using deployable wings with desirable lifting characteristics is the main theme of our paper. Additionally, the car body is streamlined in accordance with the speed range. Further, the rounded and tapered shape of the top of the car is designed to slice through the air and minimize the wind resistance. The 3D SST k-ω turbulence model has been used for capturing the intrinsic flow physics during the take off phase. In the numerical study, a fully implicit finite volume scheme of the compressible, Reynolds-Averaged, Navier-Stokes equations is employed. Through the detailed parametric analytical studies, we have conjectured that Ferrari F430 can be converted into a lucrative flying car with best fit NACA wing through a proper aerodynamic design optimization.

Keywords: aerodynamics of flying car, air taxi, Ferrari F430, roadable airplane

Procedia PDF Downloads 210
11793 Gas Flow, Time, Distance Dynamic Modelling

Authors: A. Abdul-Ameer

Abstract:

The equations governing the distance, pressure- volume flow relationships for the pipeline transportation of gaseous mixtures, are considered. A derivation based on differential calculus, for an element of this system model, is addressed. Solutions, yielding the input- output response following pressure changes, are reviewed. The technical problems associated with these analytical results are identified. Procedures resolving these difficulties providing thereby an attractive, simple, analysis route are outlined. Computed responses, validating thereby calculated predictions, are presented.

Keywords: pressure, distance, flow, dissipation, models

Procedia PDF Downloads 473