Search results for: tube feeding weaning
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 540

Search results for: tube feeding weaning

390 Temperature Effect on Sound Propagation in an Elastic Pipe with Viscoelastic Liquid

Authors: S. Levitsky, R. Bergman

Abstract:

Fluid rheology may have essential impact on sound propagation in a liquid-filled pipe, especially, in a low frequency range. Rheological parameters of liquid are temperature-sensitive, which ultimately results in a temperature dependence of the wave speed and attenuation in the waveguide. The study is devoted to modeling of this effect at sound propagation in an elastic pipe with polymeric liquid, described by generalized Maxwell model with non-zero high-frequency viscosity. It is assumed that relaxation spectrum is distributed according to the Spriggs law; temperature impact on the liquid rheology is described on the basis of the temperature-superposition principle and activation theory. The dispersion equation for the waveguide, considered as a thin-walled tube with polymeric solution, is obtained within a quasi-one-dimensional formulation. Results of the study illustrate the influence of temperature on sound propagation in the system.

Keywords: elastic tube, sound propagation, temperature effect, viscoelastic liquid

Procedia PDF Downloads 420
389 Species Composition of Lepidoptera (Insecta: Lepidoptera) Inhabited on the Saxaul (Chenopodiáceae: Haloxylon spp.) in the Desert Area of South-East Kazakhstan

Authors: N. Tumenbayeva

Abstract:

At the present time in Kazakhstan, the area for saxaul growing is strongly depopulateddue to anthropogenic and other factors. To prevent further reduction of natural haloxylon forest area their artificial crops are offered. Seed germination and survival of young plants in such haloxylon crops are very low. Insects, as one of the most important nutrient factors have appreciable effect on seed germination and saxaul productivity at the all stages of its formation. Insects, feeding on leaves, flowers, seeds and developing inside the trunk, branches, twigs, roots have a change in its formation and influence on the lifespan of saxaul. Representatives of Lepidoptera troop (Lepidopteraare the most harmful pests forsaxaul. As a result of our research we have identified 15 species of Lepidoptera living on haloxylon which display very different cycles and different types of food relations. It allows them to inhabit a variety of habitats, and feeding on various parts of saxaul. Some of them cause significant and sometimes very heavy damage for saxaul. There are 17identified species of Lepidoptera from the Coleophoridaefamily - 1, Gelechidae - 5, Pyralidae - 4, Noctuidae - 4, Lymantridae- 1, Cossidae - 2 species. At the same time we found 8 species for the first time, which have not been mentioned in the literature before. According to food specialization they are divided into monophages (2 types), oligophages (6 species) and polyphages (3 species). By affinity to plant parts, leaves and seeds are fed by 8 species, shoots by 1 specie, scions by 5 species, flowers, scions, seeds by 1, and 2species damage the roots and trunks. In whole installed seasonal groups of Lepidoptera - saxaul pests in the desert area, confined to the certain parts of the year, as well as certain parts of the plant for feeding. Harmfulness, depending on their activity appear during the growing season is also different.

Keywords: saxaul, Lepidoptera, insecta, haloxylon

Procedia PDF Downloads 323
388 An Improved Parameter Identification Method for Three Phase Induction Motor

Authors: Liang Zhao, Chong-quan Zhong

Abstract:

In order to improve the control performance of vector inverter, an improved parameter identification solution for induction motor is proposed in this paper. Dc or AC voltage is applied to the induction motor using the SVPWM through the inverter. Then stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance and mutual inductance are obtained according to the signal response. The discrete Fourier transform (DFT) is used to deal with the noise and harmonic. The impact on parameter identification caused by delays in the inverter switch tube, tube voltage drop and dead-time is avoided by effective compensation measures. Finally, the parameter identification experiment is conducted based on the vector inverter which using TMS320F2808 DSP as the core processor and results show that the strategy is verified.

Keywords: vector inverter, parameter identification, SVPWM; DFT, dead-time compensation

Procedia PDF Downloads 461
387 Maternal and Child Health Care: A Study among the Rongmeis of Manipur, India

Authors: Lorho Mary Maheo, Arundhati Maibam Devi

Abstract:

Background: Maternal and child health (MCH) cares are the health services provided to mothers and children. It includes the health promotion, preventive, curative and rehabilitation health care for mothers and children. Materials and method: The present study sample comprises of 208 women within the age range 15-69 years from two remote villages of Tamenglong District in Manipur. They were randomly chosen for assessing their health as well as the child’s health adopting an interview schedule method. Results: The findings of the study revealed that majority (80%) of the women have their first conception in their first year of married life. A decadal change has been observed with regard to the last pregnancy i.e., antenatal check-up, place of delivery as well as the service provider. However, irrespective of age of the women, home delivery is still preferred though very few are locally trained. Pre- and post-delivery resting period vary depending on the busy schedule of the agricultural works as the population under study is basically agriculturist. Postnatal care remains to be traditional as they are strongly associated with cultural beliefs and practices that continue to prevail in the studied community. Breast feeding practices such as colostrums given, initiation of breastfeeding, weaning was all taken into account.  Immunization of children has not reached the expected target owing to a variety of reasons. Maternal health care also includes use of birth control measures. The health status of women would invariably improve if family planning is meaningfully adopted. Only 10.1% of the women adopted the modern birth control implying its deep-rooted value attached to the children. Based on the self-assessment report on their health treatment a good number of the respondents resorted to self-medication even to the extent of buying allopathic medicine without a doctor’s prescription. One important finding from the study is the importance attributed to the traditional health care system which is easily affordable and accessible to the villagers. Conclusion: The overall condition of maternal and child care is way behind till now as no adequate/proper health services are available.

Keywords: antenatal, breastfeeding, child health, maternal, Tamenglong District

Procedia PDF Downloads 243
386 Study on NOₓ Emission Characteristics of Internal Gas Recirculation Technique

Authors: DaeHae Kim, MinJun Kwon, Sewon Kim

Abstract:

This study is aimed to develop ultra-low NOₓ burner using the internal recirculation of flue gas inside the combustion chamber that utilizes the momentum of intake fuel and air. Detailed experimental investigations are carried out to study these fluid dynamic effects on the emission characteristics of newly developed burner in industrial steam boiler system. Experimental parameters are distance of Venturi tube from burner, Coanda nozzle gap distance, and air sleeve length at various fuel/air ratio and thermal heat load conditions. The results showed that NOₓ concentration decreases as the distance of Venturi tube from burner increases. The CO concentration values at all operating conditions were negligible. In addition, the increase of the Coanda nozzle gap distance decreased the NOₓ concentration. It is experimentally found out that both fuel injection recirculation and air injection recirculation technique was very effective in reducing NOₓ formation.

Keywords: Coanda effect, combustion, burner, low NOₓ

Procedia PDF Downloads 201
385 Improving the Crashworthiness Characteristics of Long Steel Circular Tubes Subjected to Axial Compression by Inserting a Helical Spring

Authors: Mehdi Tajdari, Farzad Mokhtarnejad, Fatemeh Moradi, Mehdi Najafizadeh

Abstract:

Nowadays, energy absorbing devices have been widely used in all vehicles and moving parts such as railway couches, aircraft, ships and lifts. The aim is to protect these structures from serious damages while subjected to impact loads, or to minimize human injuries while collision is occurred in transportation systems. These energy-absorbing devices can dissipate kinetic energy in a wide variety of ways like friction, facture, plastic bending, crushing, cyclic plastic deformation and metal cutting. On the other hand, various structures may be used as collapsible energy absorbers. Metallic cylindrical tubes have attracted much more attention due to their high stiffness and strength combined with the low weight and ease of manufacturing process. As a matter of fact, favorable crash worthiness characteristics for energy dissipation purposes can be achieved from axial collapse of tubes while they crush progressively in symmetric modes. However, experimental and theoretical results have shown that depending on various parameters such as tube geometry, material properties of tube, boundary and loading conditions, circular tubes buckle in different modes of deformation, namely, diamond and Euler collapsing modes. It is shown that when the tube length is greater than the critical length, the tube deforms in overall Euler buckling mode, which is an inefficient mode of energy absorption and needs to be avoided in crash worthiness applications. This study develops a new method with the aim of improving energy absorption characteristics of long steel circular tubes. Inserting a helical spring into the tubes is proved experimentally to be an efficient solution. In fact when a long tube is subjected to axial compression load, the spring prevents of undesirable Euler or diamond collapsing modes. This is because the spring reinforces the internal wall of tubes and it causes symmetric deformation in tubes. In this research three specimens were prepared and three tests were performed. The dimensions of tubes were selected so that in axial compression load buckling is occurred. In the second and third tests a spring was inserted into tubes and they were subjected to axial compression load in quasi-static and impact loading, respectively. The results showed that in the second and third tests buckling were not happened and the tubes deformed in symmetric modes which are desirable in energy absorption.

Keywords: energy absorption, circular tubes, collapsing deformation, crashworthiness

Procedia PDF Downloads 340
384 Experimental Study on Capturing of Magnetic Nanoparticles Transported in an Implant Assisted Cylindrical Tube under Magnetic Field

Authors: Anurag Gaur Nidhi

Abstract:

Targeted drug delivery is a method of delivering medication to a patient in a manner that increases the concentration of the medication in some parts of the body relative to others. Targeted drug delivery seeks to concentrate the medication in the tissues of interest while reducing the relative concentration of the medication in the remaining tissues. This improves efficacy of the while reducing side effects. In the present work, we investigate the effect of magnetic field, flow rate and particle concentration on the capturing of magnetic particles transported in a stent implanted fluidic channel. Iron oxide magnetic nanoparticles (Fe3O4) nanoparticles were synthesized via co-precipitation method. The synthesized Fe3O4 nanoparticles were added in the de-ionized (DI) water to prepare the Fe3O4 magnetic particle suspended fluid. This fluid is transported in a cylindrical tube of diameter 8 mm with help of a peristaltic pump at different flow rate (25-40 ml/min). A ferromagnetic coil of SS 430 has been implanted inside the cylindrical tube to enhance the capturing of magnetic nanoparticles under magnetic field. The capturing of magnetic nanoparticles was observed at different magnetic magnetic field, flow rate and particle concentration. It is observed that capture efficiency increases from 47-67 % at magnetic field 2-5kG, respectively at particle concentration 0.6 mg/ml and at flow rate 30 ml/min. However, the capture efficiency decreases from 65 to 44 % by increasing the flow rate from 25 to 40 ml/min, respectively. Furthermore, it is observed that capture efficiency increases from 51 to 67 % by increasing the particle concentration from 0.3 to 0.6 mg/ml, respectively.

Keywords: capture efficiency, implant assisted-Magnetic drug targeting (IA-MDT), magnetic nanoparticles, In-vitro study

Procedia PDF Downloads 307
383 Characteristic of Ta Alloy Coating Films on Near-Net Shape with Different Current Densities Using MARC Process

Authors: Young Jun Lee, Tae Hyuk Lee, Kyoung Tae Park, Jong Hyeon Lee

Abstract:

The harsh atmosphere of the sulfur-iodine process used for producing hydrogen requires better corrosion resistance and mechanical properties that is possible to obtain with pure tantalum. Ta-W alloy is superior to pure tantalum but is difficult to alloy due to its high melting temperature. In this study, substrates of near-net shape (Swagelok® tube ISSG8UT4) were coated with Ta-W using the multi-anode reactive alloy coating (MARC) process in molten salt (LiF-NaF-K2TaF7) at different current densities (1, 2 and 4mA/cm2). Ta-4W coating films of uniform coating thicknesses, without any entrapped salt, were successfully deposited on Swagelok tube by electrodeposition at 1 mA/cm2. The resulting coated film with a corrosion rate of less than 0.011 mm/year was attained in hydriodic acid at 160°C, and hardness up to 12.9 % stronger than pure tantalum coated film. The alloy coating films also contributed to significant enhancement of corrosion resistance.

Keywords: tantalum, tantalum alloy, tungsten alloy, electroplating

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382 Design and Study of a Parabolic Trough Solar Collector for Generating Electricity

Authors: A. A. A. Aboalnour, Ahmed M. Amasaib, Mohammed-Almujtaba A. Mohammed-Farah, Abdelhakam, A. Noreldien

Abstract:

This paper presents a design and study of Parabolic Trough Solar Collector (PTC). Mathematical models were used in this work to find the direct and reflected solar radiation from the air layer on the surface of the earth per hour based on the total daily solar radiation on a horizontal surface. Also mathematical models had been used to calculate the radiation of the tilted surfaces. Most of the ingredients used in this project as previews data required on several solar energy applications, thermal simulation, and solar power systems. In addition, mathematical models had been used to study the flow of the fluid inside the tube (receiver), and study the effect of direct and reflected solar radiation on the pressure, temperature, speed, kinetic energy and forces of fluid inside the tube. Finally, the mathematical models had been used to study the (PTC) performances and estimate its thermal efficiency.

Keywords: CFD, experimental, mathematical models, parabolic trough, radiation

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381 The Design of Acoustic Horns for Ultrasonic Aided Tube Double Side Flange Making

Authors: Kuen-Ming Shu, Jyun-Wei Chen

Abstract:

Encapsulated O-rings are specifically designed to address the problem of sealing the most hostile chemicals and extreme temperature applications. Ultrasonic vibration hot embossing and ultrasonic welding techniques provide a fast and reliable method to fabricate encapsulated O-ring. This paper performs the design and analysis method of the acoustic horns with double extrusion to process tube double side flange simultaneously. The paper deals with study through Finite Element Method (FEM) of ultrasonic stepped horn used to process a capsulated O-ring, the theoretical dimensions of horns, and their natural frequencies and amplitudes are obtained through the simulations of COMOSOL software. Furthermore, real horns were fabricated, tested and verified to proof the practical utility of these horns.

Keywords: encapsulated O-rings, ultrasonic vibration hot embossing, flange making, acoustic horn, finite element analysis

Procedia PDF Downloads 317
380 Heat Transfer Analysis of a Multiphase Oxygen Reactor Heated by a Helical Tube in the Cu-Cl Cycle of a Hydrogen Production

Authors: Mohammed W. Abdulrahman

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In the thermochemical water splitting process by Cu-Cl cycle, oxygen gas is produced by an endothermic thermolysis process at a temperature of 530oC. Oxygen production reactor is a three-phase reactor involving cuprous chloride molten salt, copper oxychloride solid reactant and oxygen gas. To perform optimal performance, the oxygen reactor requires accurate control of heat transfer to the molten salt and decomposing solid particles within the thermolysis reactor. In this paper, the scale up analysis of the oxygen reactor that is heated by an internal helical tube is performed from the perspective of heat transfer. A heat balance of the oxygen reactor is investigated to analyze the size of the reactor that provides the required heat input for different rates of hydrogen production. It is found that the helical tube wall and the service side constitute the largest thermal resistances of the oxygen reactor system. In the analysis of this paper, the Cu-Cl cycle is assumed to be heated by two types of nuclear reactor, which are HTGR and CANDU SCWR. It is concluded that using CANDU SCWR requires more heat transfer rate by 3-4 times than that when using HTGR. The effect of the reactor aspect ratio is also studied and it is found that increasing the aspect ratio decreases the number of reactors and the rate of decrease in the number of reactors decreases by increasing the aspect ratio. Comparisons between the results of this study and pervious results of material balances in the oxygen reactor show that the size of the oxygen reactor is dominated by the heat balance rather than the material balance.

Keywords: heat transfer, Cu-Cl cycle, hydrogen production, oxygen, clean energy

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379 Investigation of Axisymmetric Bimetallic Tube Extrusion with Conic Die

Authors: A. Eghbali, M. Goodarzi, M. Hagh Panahi

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In this article process of direct extrusion of axisymmetric bimetallic tube with conic die profile and constant Mandrel by upper bound method has been analyzed and finite element method is simulated. Deformation area is divided into six smaller deformation areas and are calculated by presenting two generalized velocity field and applicable input and output sections separately (velocity profile with logarithmic curve for input section and spherical velocity profile for materials output ) for each die profile in spherical coordinate system strain rate values in every deformation area. After internal power, shearing power and material friction power is obtained, extrusion force is calculated. The results of upper bound analysis method with given results from other researcher's experiments and simulation by finite parts method (Abaqus software) are compared for conic die.

Keywords: extrusion, upper bound, axisy metric, deformation velocity field

Procedia PDF Downloads 375
378 Integrated Design of Froth Flotation Process in Sludge Oil Recovery Using Cavitation Nanobubbles for Increase the Efficiency and High Viscose Compatibility

Authors: Yolla Miranda, Marini Altyra, Karina Kalmapuspita Imas

Abstract:

Oily sludge wastes always fill in upstream and downstream petroleum industry process. Sludge still contains oil that can use for energy storage. Recycling sludge is a method to handling it for reduce the toxicity and very probable to get the remaining oil around 20% from its volume. Froth flotation, a common method based on chemical unit for separate fine solid particles from an aqueous suspension. The basic composition of froth flotation is the capture of oil droplets or small solids by air bubbles in an aqueous slurry, followed by their levitation and collection in a froth layer. This method has been known as no intensive energy requirement and easy to apply. But the low efficiency and unable treat the high viscosity become the biggest problem in froth flotation unit. This study give the design to manage the high viscosity of sludge first and then entering the froth flotation including cavitation tube on it to change the bubbles into nano particles. The recovery in flotation starts with the collision and adhesion of hydrophobic particles to the air bubbles followed by transportation of the hydrophobic particle-bubble aggregate from the collection zone to the froth zone, drainage and enrichment of the froth, and finally by its overflow removal from the cell top. The effective particle separation by froth flotation relies on the efficient capture of hydrophobic particles by air bubbles in three steps. The important step is collision. Decreasing the bubble particles will increasing the collision effect. It cause the process more efficient. The pre-treatment, froth flotation, and cavitation tube integrated each other. The design shows the integrated unit and its process.

Keywords: sludge oil recovery, froth flotation, cavitation tube, nanobubbles, high viscosity

Procedia PDF Downloads 377
377 Performance Analysis of Modified Solar Water Heating System for Climatic Condition of Allahabad, India

Authors: Kirti Tewari, Rahul Dev

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Solar water heating is a thermodynamic process of heating water using sunlight with the help of solar water heater. Thus, solar water heater is a device used to harness solar energy. In this paper, a modified solar water heating system (MSWHS) has been proposed over flat plate collector (FPC) and Evacuated tube collector (ETC). The modifications include selection of materials other than glass, and glass wool which are conventionally used for fabricating FPC and ETC. Some modifications in design have also been proposed. Its collector is made of double layer of semi-cylindrical acrylic tubes and fibre reinforced plastic (FRP) insulation base. Water tank is made of double layer of acrylic sheet except base and north wall. FRP is used in base and north wall of the water tank. A concept of equivalent thickness has been utilised for calculating the dimensions of collector plate, acrylic tube and tank. A thermal model for the proposed design of MSWHS is developed and simulation is carried out on MATLAB for the capacity of 200L MSWHS having collector area of 1.6 m2, length of acrylic tubes of 2m at an inclination angle 25° which is taken nearly equal to the latitude of the given location. Latitude of Allahabad is 24.45° N. The results show that the maximum temperature of water in tank and tube has been found to be 71.2°C and 73.3°C at 17:00hr and 16:00hr respectively in March for the climatic data of Allahabad. Theoretical performance analysis has been carried out by varying number of tubes of collector, the tank capacity and climatic data for given months of winter and summer.

Keywords: acrylic, fibre reinforced plastic, solar water heating, thermal model, conventional water heaters

Procedia PDF Downloads 337
376 Production and Investigation of Ceramic-Metal Composite from Electroless Ni Plated AlN and Al Powders

Authors: Ahmet Yönetken

Abstract:

Al metal matrix composites reinforced with AlN have been fabricated by Tube furnace sintering at various temperatures. A uniform nickel layer on Al(%1AlN)%19Ni, Al(%2AlN)%18Ni, Al(%3AlN)%17Ni, Al(%4AlN)%16Ni, Al(%5AlN)%15Ni powders were deposited prior to sintering using electroless plating technique, allowing closer surface contact than can be achieved using conventional methods such as mechanical alloying. A composite consisting of quaternary additions, a ceramic phase, AlN, within a matrix of Al, AlN, Ni has been prepared at the temperature range between 550°C and 650°C under Ar shroud. X-Ray diffraction, SEM (Scanning Electron Microscope) density, and hardness measurements were employed to characterize the properties of the specimens. Experimental results carried out for 650°C suggest that the best properties as comprehension strength σmax and hardness 681.51(HV) were obtained at 650°C, and the tube furnace sintering of electroless Al plated (%5AlN)%15Ni powders is a promising technique to produce ceramic reinforced Al (%5AlN)%15Ni composites.

Keywords: electroless nickel plating, ceramic-metal composites, powder metallurgy, sintering

Procedia PDF Downloads 237
375 The Effect of Zinc Oxide Nanoparticles on Performance Traits, Carcass Quality, Gut Morphology and Haematological Parameters of Broilers Fed Wet Diet

Authors: Farhad Ahmadi, Vafa Pahlavani, Pejman Bidar

Abstract:

This study was conducted to investigate the effect of zinc oxide nanoparticles (Nano-ZnO) on carcass quality, blood parameters, and gut morphology in broiler chickens feeding wet diets. This research was conducted by total of 300 one-day-old broiler chicks (Ross-308) were distributed into a completely randomized design inclusion of 5 treatments in 4 replicated and 15 birds in each from 1 to 42 d. The experimental diets contain: 1) diet-based on corn-soybean dry (without Nano-ZnO), 2) dry diet whit 25 mg Nano-ZnO, 3) wet diet whit 25 mg Nano-ZnO, 4) dry diet whit 50 mg Nano-ZnO, 5) wet diet whit 50 mg Nano-ZnO to wet diet. The results indicated that trail diets had no significant effect on carcass and fraction cuts in 21 age (P > 0.05). Wet feeding increased (P < 0.05) live, carcass, pancreas, gizzard, proventriculus, breast, wing and SI weight index so that the birds fed wet diet contain 50mg/kg of Nano-ZnO had the highest (P < 0.05) live, carcass, pancreas, proventriculus, gizzard, breast, wing, and gut weights at 42d compared other treatments. The birds fed diet contain 25mg/kg Nano-ZnO had the higher (P < 0.05) leg weight and lowest gizzard and gut weight than others treatment. Wet diet inclusion of 50mg Nano-ZnO increased (P < 0.05) liver weight on d 42. Experimental treatments had no significant effect on blood hematology on 21 and 42. The lymphocyte count had increased (P < 0.05) in dry than wet diet, however, monocyte Percent had significantly (P < 0.05) decreased in dry and increased in wet diets. The birds of height and height: crypts villi ratio had significantly (P < 0.05) increased on d 42, so that the highest and lowest villus height observed in 50 mg Nano-ZnO to form dry and control, respectively. In conclusion, the results of indicated that used of Nano-ZnO and wet feeding had no effect on performance parameters. Wet diet caused increased monocyte percent and 50 mg level Nano-ZnO to form dry caused increased height of villi.

Keywords: broiler, blood, gut, performance, nanoparticles

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374 CFD Modeling of Air Stream Pressure Drop inside Combustion Air Duct of Coal-Fired Power Plant with and without Airfoil

Authors: Pakawhat Khumkhreung, Yottana Khunatorn

Abstract:

The flow pattern inside rectangular intake air duct of 300 MW lignite coal-fired power plant is investigated in order to analyze and reduce overall inlet system pressure drop. The system consists of the 45-degree inlet elbow, the flow instrument, the 90-degree mitered elbow and fans, respectively. The energy loss in each section can be determined by Bernoulli’s equation and ASHRAE standard table. Hence, computational fluid dynamics (CFD) is used in this study based on Navier-Stroke equation and the standard k-epsilon turbulence modeling. Input boundary condition is 175 kg/s mass flow rate inside the 11-m2 cross sectional duct. According to the inlet air flow rate, the Reynolds number of airstream is 2.7x106 (based on the hydraulic duct diameter), thus the flow behavior is turbulence. The numerical results are validated with the real operation data. It is found that the numerical result agrees well with the operating data, and dominant loss occurs at the flow rate measurement device. Normally, the air flow rate is measured by the airfoil and it gets high pressure drop inside the duct. To overcome this problem, the airfoil is planned to be replaced with the other type measuring instrument, such as the average pitot tube which generates low pressure drop of airstream. The numerical result in case of average pitot tube shows that the pressure drop inside the inlet airstream duct is decreased significantly. It should be noted that the energy consumption of inlet air system is reduced too.

Keywords: airfoil, average pitot tube, combustion air, CFD, pressure drop, rectangular duct

Procedia PDF Downloads 157
373 Trophic Ecology of Sarotherodon Melanotheron Heudelotii and Tilapia Guineensis from the Banc D'Arguin National Park, Mauritania

Authors: Néné Gallé Kide, Mamadou Dia, Lemhaba Ould Yarba, Youssouf Kone, Fatimetou Mint Khalil, Hajar Bouksir, Ghislane Salhi, Younès Saoud

Abstract:

The diet of Sarotherodon melanotheron and Tilapia guineensis were investigated in the National Park of Banc d'Arguin (PNBA) from September 2012 to October 2013. A total of 499 individuals ranging in size between 219 and 400 mm total length of S. melanotheron (253 males and 246 females), and 280 individuals of T.guineensis (229 males and 51 females) ranged between 180 and 424mm total length. We used for studying the feeding habits of both two species the frequency of occurrence method. The coefficient of emptiness was 40.88% for S. melanotheron and 38.57% for T. guineensis. Both two species were herbivorous and very close feedings. Their diet consists of Seagrass, green, red, blue, and brown algae, diatoms, gastropods, bivalves, Crustaceans, and mud. The Seagrass and green algae were prey preference of these two species. The diet feeding showed that the composition varies slightly depending on the season and size of individuals.

Keywords: Cichlidae, trophic ecology, National park, Banc d'Arguin, Mauritania

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372 Nutritional Indices and Biology of the Armyworm, Spodoptera litura on Five Cotton Varieties

Authors: Md. Ruhul Amin

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The effects of CB1, CB3, CB5, CB8 and CB12 cotton varieties on the nutritional indices and biological parameters of armyworm Spodoptera litura were studied under laboratory conditions. The armyworm larvae showed the highest and lowest food consumption rates on CB8 and CB1 variety, respectively. The efficiency of the conversion of digested food, efficiency of conversion of ingested food, approximate digestibility rates were statistically higher and similar on CB5 and CB8, and lowest on CB1. The larvae reared on CB12 variety exerted the lowest feeding and growth indices, and the relative growth rate was highest on CB8. The survival rates of egg, larva, pupa and adult moths were found highest on CB8 and lowest on CB12. The development durations of the immature stages of the insect differed significantly and the time elapsed from egg-to-adult emergence, longevity of both male and female moths, and their lifecycle were shortest on CB12 variety. The nutritional indices and biological parameters of the armyworm indicated that the varieties CB5 and CB8 were suitable host plants for feeding and development of S. litura.

Keywords: gossypium hirsutum, spodoptera litura, food consumption, life history

Procedia PDF Downloads 382
371 Nurses' Knowledge and Practice Regarding Care of Patients Connected to Intra-Aortic Balloon Pump at Cairo University Hospitals

Authors: Tharwat Ibrahim Rushdy, Warda Youssef Mohammed Morsy, Hanaa Ali Ahmed Elfeky

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Background: Intra-aortic balloon pump (IABP) is the first and the most commonly used mechanical circulatory support for patients with acute coronary syndromes and cardiogenic shock. Therefore, critical care nurses not only have to know how to monitor and operate the IABP, but also to provide interventions for preventing possible complications. Aim of the study: To assess nurses' knowledge and practices regarding care of patients connected to IABP at the ICUs of Cairo University Hospitals. Research design: A descriptive exploratory design was utilized. Sample: Convenience samples of 40 nurses were included in the current study. Setting: This study was carried out at the Intensive Care Units of Cairo University Hospitals. Tools of data collection: Three tools were developed, tested for clarity, and feasibility: a- Nurses' personal background sheet, b- IABP nurses' knowledge self-administered questionnaire, and c- IABP Nurses' practice observational checklist. Results: The majority of the studied sample had unsatisfactory knowledge and practice level (88% & 95%) respectively with a mean of 9.45+2.94 and 30.5+8.7, respectively. Unsatisfactory knowledge was found regarding description and physiological effects, nursing care, indications, contraindications, complications, weaning, and removal of IABP in percentage of 95%, 90%, 72.5%, and 57.5%, respectively, with a mean total knowledge score of 9.45 +2.94. In addition, unsatisfactory practice was found regarding about preparation and initiation of IABP therapy, nursing practice during therapy, weaning, and removal of IABP in percentages of (97.5%, 97.5%, and 90%), respectively. Finally, knowledge level was found to differ significantly in relation to gender (t = 2.46 at P ≤ 0.018). However, gender didn't play a role in relation to practice (t = 0.086 at P≤ 0.932). Conclusion: In spite of having vital role in assessment and management of critically ill patients, critical care nurses in the current study had in general unsatisfactory knowledge and practice regarding care of patients connected to IABP. Recommendation: updating knowledge and practice of ICU nurses through carrying out continuing educational programs about IABP; strict observation of nurses' practice when caring for patients connected to IABP and provision of guidance to correct of poor practices and replication of this study on larger probability sample selected from different geographical locations.

Keywords: knowledge, practice, intra-aortic balloon pump (IABP), ICU nurses, intensive care unit (ICU), introduction

Procedia PDF Downloads 497
370 Co-Gasification of Petroleum Waste and Waste Tires: A Numerical and CFD Study

Authors: Thomas Arink, Isam Janajreh

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The petroleum industry generates significant amounts of waste in the form of drill cuttings, contaminated soil and oily sludge. Drill cuttings are a product of the off-shore drilling rigs, containing wet soil and total petroleum hydrocarbons (TPH). Contaminated soil comes from different on-shore sites and also contains TPH. The oily sludge is mainly residue or tank bottom sludge from storage tanks. The two main treatment methods currently used are incineration and thermal desorption (TD). Thermal desorption is a method where the waste material is heated to 450ºC in an anaerobic environment to release volatiles, the condensed volatiles can be used as a liquid fuel. For the thermal desorption unit dry contaminated soil is mixed with moist drill cuttings to generate a suitable mixture. By thermo gravimetric analysis (TGA) of the TD feedstock it was found that less than 50% of the TPH are released, the discharged material is stored in landfill. This study proposes co-gasification of petroleum waste with waste tires as an alternative to thermal desorption. Co-gasification with a high-calorific material is necessary since the petroleum waste consists of more than 60 wt% ash (soil/sand), causing its calorific value to be too low for gasification. Since the gasification process occurs at 900ºC and higher, close to 100% of the TPH can be released, according to the TGA. This work consists of three parts: 1. a mathematical gasification model, 2. a reactive flow CFD model and 3. experimental work on a drop tube reactor. Extensive material characterization was done by means of proximate analysis (TGA), ultimate analysis (CHNOS flash analysis) and calorific value measurements (Bomb calorimeter) for the input parameters of the mathematical and CFD model. The mathematical model is a zero dimensional model based on Gibbs energy minimization together with Lagrange multiplier; it is used to find the product species composition (molar fractions of CO, H2, CH4 etc.) for different tire/petroleum feedstock mixtures and equivalence ratios. The results of the mathematical model act as a reference for the CFD model of the drop-tube reactor. With the CFD model the efficiency and product species composition can be predicted for different mixtures and particle sizes. Finally both models are verified by experiments on a drop tube reactor (1540 mm long, 66 mm inner diameter, 1400 K maximum temperature).

Keywords: computational fluid dynamics (CFD), drop tube reactor, gasification, Gibbs energy minimization, petroleum waste, waste tires

Procedia PDF Downloads 520
369 Comparative Performance Analysis of Parabolic Trough Collector Using Twisted Tape Inserts

Authors: Atwari Rawani, Hari Narayan Singh, K. D. P. Singh

Abstract:

In this paper, an analytical investigation of the enhancement of thermal performance of parabolic trough collector (PTC) with twisted tape inserts in the absorber tube is being reported. A comparative study between the absorber with various types of twisted tape inserts and plain tube collector has been performed in turbulent flows conditions. The parametric studies were conducted to investigate the effects of system and operating parameters on the performance of the collector. The parameters such as heat gain, overall heat loss coefficient, air rise temperature and efficiency are used to analyze the relative performance of PTC. The results show that parabolic through collector with serrated twisted tape insert shows the best performance under same set of conditions under range of parameters investigated. Results reveal that for serrated twisted tape with x=1, Nusselt number/heat transfer coefficient is found to be 4.38 and 3.51 times over plain absorber of PTC at mass flow rate of 0.06 kg/s and 0.16 kg/s respectively; while corresponding enhancement in thermal efficiency is 15.7% and 5.41% respectively.

Keywords: efficiency, heat transfer, twisted tape ratio, turbulent flow

Procedia PDF Downloads 288
368 Status, Habitat Use, and Behaviour of Wintering Greater Flamingos Phoenicopterus roseus in Semi-Arid and Saharan Wetlands of Algeria

Authors: E. Bensaci, M. Saheb, Y. Nouidjem, A. Zoubiri, A. Bouzegag, M. Houhamdi

Abstract:

The Greater flamingo is considered the flagship species of wetlands across semi-arid and Saharan regions of Africa, especially Chotts and Sebkhas, which also concentrate significant numbers of bird species. Flamingos have different status (wintering and breeder) which vary between sites in different parts of Algeria. We conducted surveys and recorded banded flamingos across distinct regions within two climatic belts: semi-arid (Hauts Plateaux) and arid (Sahara), showing the importance of these sites in the migratory flyways particularly the relation between West Mediterranean and West Africa populations. The distribution of Greater flamingos varied between sites and seasons, where the concentrations mainly were in the wide, lees deep and salt lakes. Many of the sites (17) in the surveyed area were regularly supporting at least 1% of the regional population during winter. The analysis of Greater flamingos behaviour in different climatic regions in relation showed that the feeding is the dominant diurnal activity with rates exceeding 60% of the time. While feeding varies between seasons, and showed a negative relationship with the degree of disturbance.

Keywords: Algeria, greater flamingo, Phoenicopterus roseus, Sahara, semi-arid

Procedia PDF Downloads 510
367 Numerical Study of Laminar Mixed Convection Heat Transfer of a Nanofluid in a Concentric Annular Tube Using Two-Phase Mixture Model

Authors: Roghayyeh Motallebzadeh, Shahin Hajizadeh, Mohammad Reza Ghasemi

Abstract:

Laminar mixed convection heat transfer of a nanofluid with prescribed constant heat flux on the inner wall of horizontal annular tube has been studied numerically based on two-phase mixture model in different Rayleigh numbers and Azimuth angles. Effects of applying of different volume fractions of Al2O3 nanoparticles in water as a base fluid on hydrodynamic and thermal behaviours of the fluid flow such as axial velocity, secondary flow, temperature, heat transfer coefficient and friction coefficient at the inner and outer wall region, has been investigated. Conservation equations in elliptical form has been utilized and solved in three dimensions for a steady flow. It is observed that, there is a good agreement between results in this work and previously published experimental and numerical works on mixed convection in horizontal annulus. These particles cause to increase convection heat transfer coefficient of the fluid, meanwhile there is no considerable effect on friction coefficient.

Keywords: buoyancy force, laminar mixed convection, mixture model, nano-fluid, two-phase

Procedia PDF Downloads 469
366 Seasonal Profile of the Feeding Ecology of Auchenoglanis Occidentalis from Tagwai Lake, Minna Niger State, Nigeria

Authors: V. I. Chukwuemeka, S. M. Tsadu, R. O. Ojutiku, R. J. Kolo

Abstract:

The food and feeding habits of Auchenoglanis occidentalis, which is commonly called the “BuBu” cat fish or the giraffe cat fish from Tagwai Lake Minna, was analysed from January to June, 2013. A total of 216 fish specimen were used for the study which were obtained from the local fishermen operating in Tagwai Lake Minna. Fishing gears used include cast nets and gills nets of various sizes. They also use hook and lines. The frequency of occurrence and dominance method were used to analyse the food in the gut. Auchenoglanis occidentalis from Tagwai Lake, Minna had a broad spectrum of food items in the gut, ranging from insects, fish, plant materials to protozoan. The percentage of insects was (31.75%), fish (12.70%), Chyme (20.63%), plant materials (20.63%), protozoa (1.59%) and soil (12.70%). The presence of different food items in the gut of the Auchenoglanis occidentalis which ranged from animal to plant and soil made it to be considered as an omnivore bottom feeder. The food habits of this fish showed no remarkable difference between the dry season months and the rainy season months. The broad food spectrum of the fish makes them a good aquaculture candidate. It also suggests that the specie feed both in surface water and near the substratum (sand).

Keywords: Auchenoglanis occidentalis, ecology, Tagwai Lake, Nigeria

Procedia PDF Downloads 572
365 Heat Transfer Enhancement Using Aluminium Oxide Nanofluid: Effect of the Base Fluid

Authors: M. Amoura, M. Benmoussa, N. Zeraibi

Abstract:

The flow and heat transfer is an important phenomenon in engineering systems due to its wide application in electronic cooling, heat exchangers, double pane windows etc.. The enhancement of heat transfer in these systems is an essential topic from an energy saving perspective. Lower heat transfer performance when conventional fluids, such as water, engine oil and ethylene glycol are used hinders improvements in performance and causes a consequent reduction in the size of such systems. The use of solid particles as an additive suspended into the base fluid is a technique for heat transfer enhancement. Therefore, the heat transfer enhancement in a horizontal circular tube that is maintained at a constant temperature under laminar regime has been investigated numerically. A computational code applied to the problem by use of the finite volume method was developed. Nanofluid was made by dispersion of Al2O3 nanoparticles in pure water and ethylene glycol. Results illustrate that the suspended nanoparticles increase the heat transfer with an increase in the nanoparticles volume fraction and for a considered range of Reynolds numbers. On the other hand, the heat transfer is very sensitive to the base fluid.

Keywords: Al2O3 nanoparticles, circular tube, heat transfert enhancement, numerical simulation

Procedia PDF Downloads 322
364 Turbulent Forced Convection of Cu-Water Nanofluid: CFD Models Comparison

Authors: I. Behroyan, P. Ganesan, S. He, S. Sivasankaran

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This study compares the predictions of five types of Computational Fluid Dynamics (CFD) models, including two single-phase models (i.e. Newtonian and non-Newtonian) and three two-phase models (Eulerian-Eulerian, mixture and Eulerian-Lagrangian), to investigate turbulent forced convection of Cu-water nanofluid in a tube with a constant heat flux on the tube wall. The Reynolds (Re) number of the flow is between 10,000 and 25,000, while the volume fraction of Cu particles used is in the range of 0 to 2%. The commercial CFD package of ANSYS-Fluent is used. The results from the CFD models are compared with results from experimental investigations from literature. According to the results of this study, non-Newtonian single-phase model, in general, does not show a good agreement with Xuan and Li correlation in prediction of Nu number. Eulerian-Eulerian model gives inaccurate results expect for φ=0.5%. Mixture model gives a maximum error of 15%. Newtonian single-phase model and Eulerian-Lagrangian model, in overall, are the recommended models. This work can be used as a reference for selecting an appreciate model for future investigation. The study also gives a proper insight about the important factors such as Brownian motion, fluid behavior parameters and effective nanoparticle conductivity which should be considered or changed by the each model.

Keywords: heat transfer, nanofluid, single-phase models, two-phase models

Procedia PDF Downloads 484
363 Effect of the Tooling Conditions on the Machining Stability of a Milling Machine

Authors: Jui-Pui Hung, Yong-Run Chen, Wei-Cheng Shih, Shen-He Tsui, Kung-Da Wu

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This paper presents the effect on the tooling conditions on the machining stabilities of a milling machine tool. The machining stability was evaluated in different feeding direction in the X-Y plane, which was referred as the orientation-dependent machining stability. According to the machining mechanics, the machining stability was determined by the frequency response function of the cutter. Thus, we first conducted the vibration tests on the spindle tool of the milling machine to assess the tool tip frequency response functions along the principal direction of the machine tool. Then, basing on the orientation dependent stability analysis model proposed in this study, we evaluated the variation of the dynamic characteristics of the spindle tool and the corresponding machining stabilities at a specific feeding direction. Current results demonstrate that the stability boundaries and limited axial cutting depth of a specific cutter were affected to vary when it was fixed in the tool holder with different overhang length. The flute of the cutter also affects the stability boundary. When a two flute cutter was used, the critical cutting depth can be increased by 47 % as compared with the four flute cutter. The results presented in study provide valuable references for the selection of the tooling conditions for achieving high milling performance.

Keywords: tooling condition, machining stability, milling machine, chatter

Procedia PDF Downloads 431
362 Fasted and Postprandial Response of Serum Physiological Response, Hepatic Antioxidant Abilities and Hsp70 Expression in M. amblycephala Fed Different Dietary Carbohydrate

Authors: Chuanpeng Zhou

Abstract:

The effect of dietary carbohydrate (CHO) level on serum physiological response, hepatic antioxidant abilities and heat shock protein 70 (HSP70) expression of Wuchang bream (Megalobrama amblycephala) was studied. Two isonitrogenous (28.56% crude protein) and isolipidic (5.28% crude lipid) diets were formulated to contain 30% or 53% wheat starch. Diets were fed for 90 days to fish in triplicate tanks (28 fish per tank). At the end of feeding trial, significantly higher serum triglyceride level, insulin level, cortisol level, malondialdehyde (MDA) content were observed in fish fed the 53% CHO diet, while significantly lower serum total protein content, alkaline phosphatase (AKP) activity, superoxide dismutase (SOD) activity and total antioxidative capacity (T-AOC) were found in fish fed the 53% CHO diet compared with those fed the 30% diet. The relative level of hepatic heat shock protein 70 mRNA was significantly higher in the 53% CHO group than that in the 30% CHO at 6, 12, and 48 h after feeding. The results of this study indicated that ingestion of 53% dietary CHO impacted the nonspecific immune ability and caused metabolic stress of Megalobrama amblycephala.

Keywords: Megalobrama amblycephala, carbohydrate, fasted and postprandial response, immunity, Hsp70

Procedia PDF Downloads 457
361 Experimental Investigation of Folding of Rubber-Filled Circular Tubes on Energy Absorption Capacity

Authors: MohammadSadegh SaeediFakher, Jafar Rouzegar, Hassan Assaee

Abstract:

In this research, mechanical behavior and energy absorption capacity of empty and rubber-filled brazen circular tubes under quasi-static axial loading are investigated, experimentally. The brazen tubes were cut out of commercially available brazen circular tubes with the same length and diameter. Some of the specimens were filled with rubbers with three different shores and also, an empty tube was prepared. The specimens were axially compressed between two rigid plates in a quasi-static process using a Zwick testing machine. Load-displacement diagrams and energy absorption of the tested tubes were extracted from experimental data. The results show that filling the brazen tubes with rubber causes those to absorb more energy and the energy absorption of specimens are increased by increasing the shore of rubbers. In comparison to the empty tube, the first fold for the rubber-filled tubes occurs at lower load and it can be concluded that the rubber-filled tubes are better energy absorbers than the empty tubes. Also, in contrast with the empty tubes, the tubes that were filled with lower rubber shore deform asymmetrically.

Keywords: axial compression, quasi-static loading, folding, energy absorbers, rubber-filled tubes

Procedia PDF Downloads 429