bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Load and Interface Materials on Thermal Contact Resistance between Similar and Dissimilar Materials
Authors: Narayana Swamy R. , Narayan Prabhu K.
Published: July 2014

The thermal contact resistance (TCR) between similar and dissimilar materials (copper, aluminium, brass and type 304 stainless steel) was assessed. Copper foil, aluminium foil, lead and Sn-9Zn lead free solder were selected as thermal interface materials (TIMs). The interfacial contact pressure was varied by application of load on materials in contact. The interfacial heat flux was estimated by solving the inverse heat conduction problem (IHCP). At higher load, the temporal variation of thermal contact resistance showed early occurrence of peak and lower values of TCR. The use of thermal interface materials reduced the contact resistance between the hot source and cold sink materials. Among the interface materials used, Sn-9Zn lead free solder showed the lowest contact resistance. This was attributed to the solid to liquid phase transformation at higher temperatures and the conformance of the interface material to surfaces in contact. Factorial experiments were carried out to determine the significance of experimental variables on TCR. The analysis showed that the effect of applied load on TCR was significant compared to other parameters.
Effect of Methanol Additive with LPG in Three Cylinder Four Stroke S.I. Engine
Authors: Somasundaram S. , Mohanraj T. , Pasupathy Raju S.
Published: July 2014

LPG is a mixture of gas, mainly propane and butane. It is commonly used as a fuel for cooking and as a transportation fuel. It is normally created as a by-product of petroleum refining and from the production of Natural Gas. An experiment is conducted to obtain the operating characteristics of the four stroke three cylinder inline water cooled spark ignition engine operated with LPG and methanol. The engine is started with LPG and methanol with various ratios at constant volume rate in the vaporizer. Solenoid valve was used to allow either LPG or petrol in the carburetor. The LPG supplied through the vaporizer and the quantity is metered by hanging type weighing scale. The additives are added with LPG before supplied to the vaporizer. The performance characteristics of engine were analyzed using petrol with increase in load. Further the engine run with LPG and adjusts the flow based on the mixing of additives. The best ratio of additives can be selected based on the experimental results obtained in the engine.The findings of the present research work suggest that optimum % of methanol as additive to increase the overall performance and to reduce the emission levels.
Effect of Operating Temperature on the Performance and Thermal Load of Water/Lithium Bromide Vapour Absorption Heat Pump in the Absence of Solution Heat Exchanger
Authors: Manu S. , Chandrashekar T.K. , Antony A.J.
Published: July 2014

In this investigation, a thorough thermodynamic analysis of the water/lithium bromide absorption refrigeration cycle in the absence of solution heat exchanger is performed. The influence of operating temperature on the thermal loads of components, COPc (Carnot Coefficient of Performance), COPE (Enthalpy based Coefficient of Performance) and efficiency ratio (η) is studied. It is concluded that the COPc and COPE values decreases with increasing condenser and absorber temperature but increase with increasing generator and evaporator temperatures .
Effect of Piston Shape on Scavenging in a Two-Stroke Engine - A CFD Analysis
Authors: Agrawal Vivek , Mallikarjuna J.M.
Published: July 2014

This study focuses on effect of piston shape on in-cylinder flows in a conventional loop scavenged two-stroke engine using CFD. Three piston-shapes viz., flat, flat with center-bowl and flat with center-dome are analyzed along with standard piston. The CFD solution has been obtained by using commercial code STAR-CD. First the CFD results are compared with those of experimental values obtained from particle image velocimetry (PIV). For comparison among various piston shapes, various parameters viz., velocity vector plots, tumble ratio (TR), turbulent kinetic energy (TKE) at various crank angles are used. Scavenging and trapping efficiencies are also calculated for each piston configuration. From the results, it is found that flat with center-bowl piston is the best in terms of in-cylinder flow characteristics. It gives higher TR and TKE with very little effect on efficiencies.
Exhaust Manifold Waste Heat Recovery System of a Single Cylinder Engine
Authors: Tiwari Neha , Singh Appu Kumar , Vishwakarma Tejas , Sharma Harshal , Suhail Mohammed
Published: July 2014

The current worldwide trend of rapid economic development and increasing energy requirement in the transportation sector are one of many segments that is responsible for a growing share of fossil fuel usage. Supply and demand for fuel is accelerating prices and eventually will affect availability. The selected contemporary paper will address on how a prototype Stirling engine capable of reining in waste heat spilling out of the typical engine exhaust and its intensity level to oppose against the tyranny of inefficiency. Stirling engine systems are fuel flexible with respect to source of thermal energy and unprocessed waste heat that resulting in entropy rise can be harvested to power Ancillaries and increase overall efficiency. The preliminary prototype design and methodology follows process, heat to mechanical energy and latter to electrical energy. Experimental verification of analytical data was carried out and presented here. The shortcomings of these methods are highlighted and an alternative approach to solving particulars suggested.
Expansion Joint Design, Manufacture and Testing for Large Capacity Steam Turbines
Authors: Pargaonkar C.S. , Batrani Maneesh
Published: July 2014

The rapidly growing trend for higher capacity steam turbines with large steam flows demand the use of long lengths and large size pipes. Thermal expansions of up-to 50mm and pipe diameters up-to 2600mm are required to be dealt with calling for the use of Expansion Joints to control the stresses in both the pipes as well as the end equipment. The bellows in the Expansion Joints used for the steam turbine application are stretched to their limiting values of the stresses in order to make them as flexible as possible with the aim of limiting the pipe and end equipment operational stresses. Three fundamental types of loading are presented to provide insight into the way bellows convolutions are stressed during operation. The optimization of the bellows profile geometry is discussed briefly. A comparison of the resulsts obtainied by proven computational methods as well as by using international EJMA standard is made to highlight the safety built in the well established methods used.
Experimental Analysis of Cardanol Biofuel as an Alternative Fuel for Diesel Engines with Air-Side Oxygen Enrichment
Authors: Dinesha P. , Nayak Vighnesha , Kumar Dheeraj , Mohanan P.
Published: July 2014

The present study investigates the effect of air-side oxygen concentration enrichment on the performance and emission of a single cylinder diesel engine using a bio-fuel blend as fuel. In this study, a natural phenolic compound, namely, cardanol is selected as the bio-fuel, which is obtained from the shell of cashew nut after purification. A blend of B10M10 (10% cardanol +10% methanol + 80% diesel by volume) is prepared and tested in the engine at various loading conditions. The experiments are carried out at atmospheric oxygen condition and an increment of 3, 5, and 7% of atmospheric oxygen concentration by weight. There is a drastic reduction in HC, CO, and smoke except for NOx emission. The level of NOx emission increases as the oxygen concentration in the intake air is increased. The performance characteristic will increase as the oxygen concentration increases, and higher brake thermal efficiency is obtained for B10M10 at 7% oxygen concentration. B10M10 with 7% oxygen enrichment gives better results, similar to diesel, except for NOx emission.
Experimental Investigation of Performance of Spiral Coil in Spiral Tube Heat Exchanger
Authors: Deshpande G.N. , Sali Nitin V.
Published: July 2014

In the present work of experimental investigation, the heat transfer performance of Spiral Tube Heat Exchanger (STHE) is studied by manufacturing the heat exchanger. STHEs are known as excellent heat exchanger because it is compact in size and having high heat transfer ability. The STHE consists of copper coils in the spiral shape and placed inside the shell which is made of Stainless Steel. The spiral shape coil is made by bending the straight copper tube of 10 mm inside diameter. The heat exchanger uses 3 such spiral coil brazed with straight header tube of 25 mm inside diameter and at a distance of 15mm apart, the number of turn in a spiral coil is four. Pump is used for circulation of water in both circuits. Cold water is circulated through spiral coil which entered at the periphery and comes out from centre; hot water is entered at the bottom centre of shell and comes out from the top of the shell. The inlet temperature range of hot water and cold water is 50 to 80°C and 30 to 48°C. Mass flow rate range of hot water and cold water is from 0.0633 kg/s to 0.0833kg/s and 0.01 kg/s to 0.0833kg/s.
Experimental Investigation on Droplet Cooling of Brakes
Authors: Kathiresan K. , Adhavan J. , Venkatesan M.
Published: July 2014

Braking system is one of the important systems in Automobiles. It is essential to decelerate the vehicle and stop it when essential. The temperature of the brake pad (stator) and disc (rotor) increases because of frictional force between them. Higher temperatures may lead to brake fading or failure of braking system. In the present study droplet cooling of commercially available Brake pad is analyzed with surface temperatures in the range of 80°C - 150°C. The brake pad material analyzed is a composite material with Fe2O3, BaO, CaO, SiO2, SO3 and MgO as major constituents. The percentage of the constituents are found using Scanning Electron Microscope (SEM). The brake pad is artificially heated using cartridge heater and a fixed volume of water is dropped on to the brake pad surface using a syringe pump. The characteristics of droplet on the surface of the brake pad are recorded using a High speed camera. The temperature is measured continuously using a K type thermocouple and is recorded using an online data acquisition system. The characteristic of droplet enhanced cooling is presented.
Experimental Investigations on Heat Transfer Enhancement in a Horizontal Tube Using Converging and Diverging Conical Strip Inserts
Authors: G Ravi , Devi Sri Rama R. , Gugulothu Ravi
Published: July 2014

The present work deals with the results of the experimental investigations carried out on augmentation of turbulent flow heat transfer in a horizontal circular tube by means of tube inserts, with air as working fluid. Experiments were carried out initially for the plain tube (without tube inserts). The Nusselt number and friction factor obtained experimentally were validated against those obtained from theoretical correlations.
Secondly experimental investigations using three kinds of tube inserts namely Rectangular bar with diverging conical strips, Rectangular bar with converging conical strips, Rectangular bar with alternate converging diverging conical strips were carried out to estimate the enhancement of heat transfer rate for air in the presence of inserts. The Reynolds number ranged from 8000 to 19000. In the presence of inserts, Nusselt number and pressure drop increased, overall enhancement ratio is calculated to determine the optimum geometry of the tube insert.
Based on experimental investigations, it is observed that, the enhancement of heat transfer using Rectangular bar with converging and diverging conical strips is more effective compared to other inserts.
Key words: Heat transfer, enhancement, turbulent flow, conical strip inserts, friction factor, pressure drop.
Experimental Study of Heat Transfer Enhancement in Pool Boiling by Using 2-Ethyl 1-Hexanol an Additive
Authors: Gajghate Sameer Sheshrao , Aacharya Anil R. , Pise Anil T. , Jadhav Ganesh S.
Published: July 2014

The addition of additives to the water is known to enhance boiling heat transfer. In the present investigation, boiling heat transfer coefficients are measured for Nichrome wire, immersed in saturated water with & without additive. An additive used is 2-Ethyl 1-Hexanol with varying concentrations in the range of 10-10000 ppm. Extensive experimentation of pool boiling is carried out above the critical heat flux. Boiling behavior i.e. bubble dynamics are observed at higher heat flux for nucleate boiling of water over wide ranges of concentration of additive in water. Results are encouraging and show that a small amount of surface active additive makes the nucleate boiling heat transfer coefficient considerably higher, and that there is an optimum additive (500-1000ppm) concentration for higher heat fluxes. An optimum level of enhancement is observed up to a certain amount of additive 500-1000ppm in the tested range. Thereafter significant enhancement is not observed. This enhancement may be due to change in thermo-physical properties i.e. mainly due to a reduction in surface tension of water in the presence of additive.
Heat Transfer Analysis of Motorcycle Engine Cylinder Using CFD under Various Fin Geometries and Speed Condition
Authors: Ranjan Amit , Das D.H.
Published: July 2014

In thisstudy, the heat transfer analysis of internal combustion engine of motorbike is performed with the various fin geometries. Generally rectangular fins are used for motorbike but still this fin geometry could be modified to increase the heat transfer rate.A numerical investigation is carried out for two geometries such as annular and wavy, of finned engine cylinder using CFD and the results are compared. Various experimental methods are presented in literature to see the effect of wind velocity, fin geometry and the ambient temperature on heat transfer rate. In the present paper an effort is made to study the effect of wind velocities and fins geometries on the heat transfer rate and simulation of the heat transfer using CFD. The models are generated in CATIA V5 and simulated in FLUENT software. The results show that the heat transfer rate and effectiveness of the wavy fins is better than for the annular fins.
Influence of Fuel Injection Timing on the Performance and Emission Characteristics of a Diesel Engine Fueled with Jatropha Methyl Ester-Tyre Pyrolysis Oil Blend
Authors: Sharma Abhishek , Murugan S.
Published: July 2014

Early investigation on utilization of Jatropha methyl ester (JME) tyre pyrolysis oil (TPO) blends in a single cylinder, constant speed, direct injection diesel engine revealed that a blend of 80% JME and 20% TPO referred to as JMETPO20 blend give a better performance and lower emissions compared to other Jatropha methyl ester tyre pyrolysis oil (JMETPO) blends. In this study, for further improvement on performance and emission characteristics, and also to find optimum injection timing for blend, experiments have been carried out with varying the injection timing. Tests have been conducted under two advanced and two reratarded injection timings in addition to the original injection timing of 23 °CA bTDC. The experimental test results showed that for the JMETPO20 blend at advanced injection timing of 24.5 °CA the brake thermal efficiency increased by about 2.21%, compared to the result of original injection timing at full load. For the JMETPO20 blend at advanced injection timing of 24.5 °CA the nitric oxide and carbon dioxide emission increased by about 4.56% and 11.91% respectively at full load, and the carbon monoxide emission decreased by about 11.21%, compared to that of original injection timing.
Development of Tool Based Micromilling/Microdrilling Machine with Piezoactuated Workpiece Feeding System
Authors: Veeresha R. K. , Muralidhara Muralidhara , Rao Rathnamala
Published: July 2014

Tool based mechanical micromachining technology is gaining importance in MEMS device fabrication because of its ability to machine 3D micro features on different engineering materials. This paper presents the development of tool based mechanical micromachining center with piezoactuated workpiece feeding system. A high speed spindle is used to rotate the micromilling/drilling tool at a speed of 12,000 to 60,000 rpm. A thermoelectric based liquid cooling system is developed to control the temperature of the high speed spindle at a set value. Along with the X-Y positioning system, the workpiece is also mounted on a piezoactuator to provide Z-axis motion during machining operation. An electrical continuity based tool-workpiece contact detection system is developed to overcome premature tool failure during initial tool registration with the workpiece. Based on the developed tool-workpiece contact sensor, an in-situ measurement system is developed to measure the micromachining depth. Experiments were conducted to measure the performance of spindle cooling system and in-situ measurement system.
Microcalorimetry and Kinetics of Biodiesel
Authors: Sivapirakasham S.P. , Khan A. Afsal , Yogesh Mane G. , Anand R.
Published: July 2014

Now a day biodiesel becomes best alternative for diesel fuel. Thermogravimetry technique has great acceptance in the field of fossil fuel. The thermal and kinetics properties of diesel and Jatropha biodiesel are analyzed by using popular technique of thermogravimetry. The aim is to study the behavior of diesel, biodiesel and their blends in Nitrogen gas atmosphere at the heating rate of 5K/min, 10K/min and 15K/min from 30°C to 600°C. From study it is found that as heating rate increases peak is shifting toward higher value which shows that there is less uniform heating. The study clearly shows biodiesel is more stable than diesel indicating that transesterification make sample less stable. The Arrehenius Kinetic model is applied to study the activation energy. As percentage of biodiesel increases, stability of sample increases and hence increases in activation energy
Natural Convection Flows in Porous Square Enclosures with Different Aspect Ratios
Authors: Aparna K. , Karthik K. , Seetharamu K.N.
Published: July 2014

Natural convection is studied numerically using finite element based computational procedure. The enclosure used for flow and heat transfer analysis has been bounded by adiabatic top wall, constant temperature cold vertical walls and a horizontal bottom wall. The grid independent study has been made with different grids to yield consistent values. Different grid sizes 30x30, 40x40, 50x50 uniform meshes have been studied. Study shows the convergence of average Nusselt number for a grid size of 41x41. Hence a grid size of 40x40 is used in all computations. Nusselt numbers are computed for different Rayleigh’s numbers (Ra) and aspect ratios of 1,2 and 3. Results are presented in the form of streamlines, isotherm plots and average Nusselt number. The average Nusselt numbers increase with Rayleigh number and for a given Ra, increase in Nu is obtained with increase in aspect ratio for bottom wall.
Numerical Study on Proton Exchange Membrane Fuel Cell with 2mm×2mm and 25cm2 Serpentine Flow Channel
Authors: Vaibhav Pal , Karthikeyan P. , Anand R.
Published: July 2014

As fossil fuels are becoming less reliable and more costly, the Proton Exchange Membrane Fuel Cell (PEMFC) is emerging as the primary candidate to replace the stationary and transport applications. In this study numerical simulation on PEMFC is done by commercially available Computational Fluid Dynamics (CFD) software. A three-dimensional, model of a single PEM Fuel cell with serpentine flow field design has been used for the study. The numerical model is 3-D steady, incompressible, single phase and isothermal includes the governing of mass, momentum, energy, and species along with electrochemical equations. All of these equations are simultaneously solved in order to get current flux density and H2, O2 and H2O fractions along the flow field design.
Performance and Emission Characteristics of a Diesel Engine with Various Injection Pressures Using Bael Biodiesel
Authors: Dhanamurugan A. , Subramanian R.
Published: July 2014

Fuel injection pressures in diesel engines play an important role to distribute the fuel jet quickly and to form a uniform gas mixture after fuel injection in order to reduce fuel consumption and emissions. In this study, an attempt has been made to study the effect of injection pressure on a single cylinder direct injection diesel engine fueled with diesel, diesel – bael biodiesel blend (B20) and methyl ester of bael (Aegle marmelos) seed oil with injection pressures of 220,230,240 and 250 bar. Increasing the injector opening pressure has been found to increase brake thermal efficiency and reduce CO, HC and smoke emissions significantly. The optimum injection pressure was found to be 240 bar for bael seed biodiesel.
Radiation Adhered with Conduction Heat Transfer Adopting Finite Volume Method
Authors: Nashine Prerana , Satapathy Ashok Kumar
Published: July 2014

This article considers a radiative transport problem coupled with conduction in the one dimensional slab in the presence of participating media. The finite volume method of computation is presented to discretize the radiative transfer equation over the control volume and by using the error function, conduction term is being computed. In the mathematical derivation the RTE is integrated with respect to control volume and control angles with the freedom in choosing number of angular nodes. The results reveals that the proposed method is a promising alternative to the well-established practices like the discrete ordinates method (DOM), discrete transfer method (DTM), monte-carlo method and many more.
Dry Sliding Wear Performance of A356 Alloy with Minor Additions of Magnesium
Authors: M.S. Prabhudev , Auradi Virupaxi , Venkateshwarlu Karodi , Suresha S.M. , Kori S.A.
Published: July 2014

In the present investigation, effect of minor additions of magnesium (Mg) content on the dry sliding wear behavior of A356 alloy has been reported. Alloy composition, normal pressures and sliding distances on A356 alloy has been studied. The worn surfaces were characterized by SEM microanalysis. The results indicate that, the wear rate of A356 alloy increases with increase in normal pressures and sliding distances in all the cases and decreases with 0.7% Mg addition to the A356 alloy. This is due to the change in microstructure resulting in improvement of hardness and strength of the alloy. The worn surface study indicates that, the formation of oxide layer between the mating surfaces during sliding improves sliding wear performance.
Reductions of Bio-Diesel Exhaust Emissions through Engine Combustion Chamber Design Modifications — An Experimental Study
Authors: Rajashekhar C.R. , Chandrashekar T.K. , Umashankar C. , Harish Kumar R.
Published: July 2014

Increased demand and production in all segments of the automotive industry has driven the nation to impose stringent emission norms for automobile engines. At this juncture, bio-diesel has sufficient attraction as vehicular fuel. But the properties of bio-diesels are not the same as diesel fuels, including high viscosity and low volatility. Due to this inherent problem it exhibits poor atomization, which results in incomplete combustion and increased exhaust emissions. This naturally implies that automotive designers have to focus their research more on engine emissions while at the same time not compromising on power development. This has put enormous pressure on automotive industry to design the engine efficiently and economically to compete with the global market. This paper relates the modification of engine combustion chamber design, for inducing turbulence to improve the combustibility of combustible mixture of karanja bio-diesel and to reduce the exhaust emissions. The modification includes the tri-chambered piston and twisting blade pistons. In the present work the emission characteristics of modified piston engine are compared with the standard piston engine. It was observed that the CO and UBHC emissions can be effectively reduced with tri-chambered piston engine.
Review of Solar Cooking Using Latent Heat Storage
Authors: Gore Bhagwat , Tandale Madhukar
Published: July 2014

Use of latent heat storage system using Phase Change Materials (PCM) is an effective way of storing thermal energy and has several advantages like high storage density, isothermal nature of the energy storage etc. Solar cooking is one of the solutions to overcome increasing demand of fossil fuels in country like India. However it suffers from problems like low solar intensity, fluctuations during cloudy environment, limited availability (only during few hours of the day), and fluctuations with time. Use of latent heat storage system in solar cooking, can overcome some of the problems listed above. In this paper, efforts were made to gather the information on previous works on solar cooking system using PCM, use of Phase Change Materials (PCMs) for evening / night cooking and conceptual design of solar cooker using PCM. This review will be important for further research in this field. Heat storage system enables cooking food during cloudy sky or in the evening. Hence, solar cooker with PCM storage will increase the utility and reliability of the solar cookers. As the source temperature raises, the chemical bonds within the PCM breaks which changes phase from solid to liquid. The phase change is a heat-seeking (endothermic) process and therefore, the PCM absorbs heat on melting. Upon storing heat in the storage material, the material begins to melt when the phase change temperature is reached. The temperature then stays constant until the melting process is completed. The solar energy stored during day time can be used directly for cooking or can be stored in PCM and used during night/evening time.
Steady State Analysis on Efficiency Improving Methods for Series Flat Plate Solar Water Heaters
Authors: Sridharan M. , Siva Prakash E. , Prasanna N.
Published: July 2014

Now a day’s different types of solar flat plate collectors are in use. Out of which only few type of collectors proved their performance by producing better results of expected level. In this paper a new set of collectors are combined as mean to improve performance of series SFPC collectors available in market now a days. In such new combination a collector with reduced overall loss coefficient was used to improve the efficiency of the existing system. New collector with zig-zag flow pattern gives a slight change in flow path. Thus the objective of this experimental analysis is to improve efficiency with new set of series FPC by comparing with existing series FPC. Experimental results obtained give better and higher results suggested by theoretical analysis.
Effect of Boron Carbide and Graphite on Machining Characteristics of Aluminium Boron Carbide Composite
Authors: Rajkumar K. , Rajan P.
Published: July 2014

This paper presents the mechanical and machinability properties of aluminium 6061 alloy reinforced with boron carbide composite is compared with the addition of graphite particles with AlB4C. The composites were fabricated by stir casting process. The experimental results showed that the hardness of the composite increases with the increasing addition of boron carbide. Tests for machinability characteristics was carried out with carbide tool at different cutting speeds keeping feed and depth of cut as constant. The machining tests revealed that the addition of graphite to Al-B4C composite has enhanced its machining properties.
Thermal Error Modelling in CNC Machines
Authors: Jamuna R. , Natarajan U.
Published: July 2014

Latest trend in increasing the performance characteristics of precision machines is reducing error in machines. Today research is focused on Machine tool accuracy. The effect of thermal error contributes to major part of 70% of volumetric error. The present study aims to establish a new compensation method for CNC Turning centre. Selection of proper temperature variables is a great task in thermal error compensation. In this paper 3 thermal process variables namely spindle speed; temperature and time are used to create thermal error models. Using ANSYS simulation experiments are created.
Thermochemical Cycles for Hydrogen Production
Authors: Babu N. Narendra , Jayaraj S. , Pavan Kumar M.V. , Kamath H.C.
Published: July 2014

Increasing energy consumption, high cost and exhaustible nature of fossil fuels and their impacts on environment have increased interest in production of hydrogen from thermochemical cycles by harvesting energy from renewable energy sources in the present scenario. By using thermochemical cycles the large quantity of hydrogen production is possible. The main thermochemical cycles out of all reference cycles are Cu-Cl, Zn-ZnO, S-I, Ca-Br and Fe-Cl.
Thermodynamic Analysis of Heat and Mass Transfer Enhancement for R134a-DMAC/CNT Vapour Absorption Refrigeration System
Authors: Kathiravan A. , Karthikeyan E. , Mariappan V. , Muthiah Chidambaram T.
Published: July 2014

The objective of this paper is to study thermodynamic analysis of R134a-DMAC and R134a-DMAC/CNT vapour absorption system and compare this both system performance. This investigation for R134a-DMAC is carried out based on the correlations available in the literature. The change of thermophysical properties for R134a-DMAC/CNT is predicted and is incorporated in the pure R134a-DMAC correlations. The analysis is carried for 1 kW evaporator capacity and effectiveness of solution heat exchanger is taken as 0.8. Variations in the performance parameters of the system with and without nano fluids are studied against various operating temperatures of generator, absorber and different volume concentration. The result of this theoretical study shows that co-efficient of performance (COP) of system with CNT nano fluid is improved as well as the absorber capacity also increased due to enhanced heat transfer of nano fluids. It also observed that the performance achieved by the pure R134a-DMAC at the elevated generator temperature could be achieved at low generator temperature using R134a-DMAC/CNT.
Working Characteristics of a C.I. Engine Fuelled with Oxygenates as Additives in Jatropha Biodiesel
Authors: Prabu A. , Anand R.B.
Published: July 2014

An experimental investigation is conducted for studying the effect of the oxygenates blended with Jatropha biodiesel in a single cylinder Direct Injection diesel engine by using AVL 444 Di-gas analyzer for measuring level of pollutants at engine exhaust and AVL 437 smoke meter for measuring smoke opacity. Two oxygenated additives namely Ethylene Glycol (C2H6O2) and Propylene Glycol (C3H8O2) are added equally to neat biodiesel at geometric sequence (1, 2 and 4 %) forming the blends EGPG1 (Biodiesel + 0.5 % Ethylene Glycol + 0.5 % Propylene Glycol), EGPG2 (Biodiesel + 1 % Ethylene Glycol + 1 % Propylene Glycol) and EGPG4 (Biodiesel + 2 % Ethylene Glycol + 2 % Propylene Glycol). This paper highlights the effect of two oxygenates added as additive in biodiesel, that affecting the performance and emission characteristics of the engine. Marginal improvement in the performance of the engine and reduced level of pollutant such as Carbon monoxide (CO) and Smoke opacity for the test fuels are observed with slight increase in NO ( Nitrogen oxide ) and Unburned Hydro carbon (UHC) emission.
Effect of Carbon Fiber, Silica and Fly-Ash Particulate Addition on Tensile and Impact Behaviour of Polyester and Epoxy Resin
Authors: Kumar P. Nantha , Rajadurai A.
Published: July 2014

Thermosetting and thermoplastic resins are becoming widely accepted alternate materials in engineering industry. Industries seek alternate materials starting from containers to aircraft parts for reducing weight and increasing durability. Mere resin based plastic components may not fulfil these requirements. Fiber materials are added in composites to increase the strength, whereas filler materials are generally inert materials which are added to reduce material cost and to improve the mechanical properties such as hardness and wear resistance to some extent. In this paper the effect of carbon fibre, silica and fly-ash particulate addition on the tensile and impact behaviour of polyester and epoxy resin are investigated. The composite laminates were fabricated by hand layup method and cured in room temperature. Tensile and impact properties are increased on addition of carbon fiber up to 30% by weight. Addition of fly-ash particulate and silica in micron sizes decresed the tensile and impact strength.
Design and Fabrication of Single Effect Absorption Cooling System of 5.25kW Cooling Capacity for Domestic Use
Authors: Raja V.Boopathi , Shanmugam V.
Published: July 2014

The aim of this work is to design and fabricate solar assisted single effect absorption cooling system of 5.25 kW cooling capacity to cool a room having floor area of 15m2. The design of the major components of the cooling system like generator, condenser, evaporator, absorber and solution heat exchanger are described in this paper.
Comparison of Performance of Diesel and LPG Blends in Dual Fuel Engine with Tallow Methyl Ester (TME) as a Fuel
Authors: Hariprasad Tarigonda , Rao P. Mallikarjuna , Reddy R. Meenakshi
Published: July 2014

Bio-diesel manufactured from vegetable oils, animal fats and used cooking oils is an alternative fuel for diesel engines. It offers many advantages such as renewable, energy efficient, nontoxic, sulfur free and bio-degradable, and also offers cleaner combustion and reduces global warming gas emissions. Experiments are conducted by fuelling the diesel engine with bio-diesel with LPG blends. The engine is properly modified to operate under dual fuel operation using LPG as the mixed fuel along with Diesel and TME as ignition source. The brake thermal efficiency of TME with LPG (2LPM) blend is increased at an average of 5%.HC emissions of TME with LPG (2LPM) blend is reduced by about at an average 21%. CO emissions of TME with LPG (2LPM) blends are reduced at an average of 33.6%. NOx emissions of TME with LPG (2LPM) blend are reduced at an average of 4.4%. Smoke Opacity of TME with LPG (2LPM) blend is reduced at an average of 10%. Keywords Biodiesel, diesel engine, alternate fuels, tallow oil and methyl esters of tallow oil, LPG
CFD Modelling of Biomass Gasification in Fluidized-Bed Reactor Using the Eulerian-Eulerian Approach
Authors: Thankachan Issac , Rupesh S. , Muraleedharan C.
Published: July 2014

A comprehensive two dimensional numerical model has been developed to simulate the biomass gasification in a fluidised bed reactor. Gas-solid flows as well as the chemical reactions are considered. Euler-Euler model is adopted to describe the multiphase flow regime inside the reactor. The standard k-є model is used to model the turbulence for each phase. The particle motion inside the reactor is modelled using various drag laws derived from Kinetic Theory of Granular Flow. Biomass fuel after pyrolysis is fed as char and volatile matter. The reaction rates of homogeneous reactions and heterogeneous reactions are determined by Eddy dissipation reaction rate and Arrhenius-Diffusion reaction rate, respectively. Gas velocities, flow patterns, composition of gas product and distribution of reaction rates are obtained. Results are compared with experimental data and found to be in agreement.
Flow Visualization Study on Radial Flow Pump under Cavitating Condition
Authors: Christopher S. , Kumaraswamy Sivasailam
Published: July 2014

The aim of this paper was to present a method to identify the extent of cavitation in pump using the photographic records of cavitation tests conducted on pumps having three different leading edge profiles of the vane. Based on the extent of cavitation in pump, the impeller with circular leading edge was found to be better in operation, followed by plain and ellipse2 leading edge impellers. The technique adapted here was useful to correlate the extent of cavitation with the head drop in pump.
Effect of Chills on the Microstructure and Mechanical Properties of Carbidic Austempered Ductile Iron
Authors: Prem Kumar R. , Mohamed Nazirudeen S.S. , Anburaj J.
Published: July 2014

Carbidic Austempered Ductile Iron (CADI) is a recent addition to the Austempered Ductile Iron (ADI) family. The effect of chills on the microstructure and mechanical properties of CADI was investigated after Austempering. Three samples of chromium alloyed CADI, the first sample without chill, the second sample with bottom chill and the third sample with bottom and side chills were produced in order to evaluate the effect of chills on its mechanical properties. The samples were austenised for 2 hours at 925° C and then austempered at 325° C for 2 hours in a salt bath furnace. The microstructural features of the as-cast and the austempered CADI samples were analysed using Optical Microscope and Scanning Electron Microscope (SEM). The mechanical properties of the CADI samples (as-cast and austempered) were evaluated for hardness, impact and wear. By austempering at 325° C for 2 hours a typical microstructure of bainite was produced in all the three samples. Hardness and wear resistance of austempered samples produced using bottom and side chills were considerably higher than the corresponding values in samples produced without using any chill and also by using only bottom chill. This enhanced mechanical property in the bottom and side chill sample is attributed to the presence of bainite, carbides and more of uniform fine graphite nodules.
Numerical Simulation of Two Dimensional Laminar Wall Jet Flow over Solid Obstacle
Authors: Arul Prakash M , Mayilsamy K. , Kanna P. Rajesh
Published: July 2014

A Computational Fluid Dynamics code was developed to study the flow characteristics of two dimensional laminar incompressible flow. Stream function-vorticity formulation was used for solving two dimensional continuity and momentum equations. The unsteady vorticity transport equation is solved by alternate direction implicit scheme. The stream function equation is solved by the successive over relaxation method. A computational code in c-language was developed to solve the tridiagonal system of algebraic equations. Two dimensional flow through a channel with rectangular block at the bottom wall was considered for the validation. The streamline patterns obtained for different Reynolds number shows good agreement with published results. The code was modified to simulate an incompressible laminar wall jet flow around a solid obstacle. Simulations were carried out for different Reynolds numbers. Contour plots of Stream line, u-velocity and v-velocity were obtained. The variations of flow patterns and the development of vortices were studied and reported.
Pneumatic Transport of Coarse Grain Particle Using Air Mass Balance Model
Authors: Mukherjee Abhisekh , Dhar Mrinmoy , Barman Nilkanta
Published: July 2014

In this work, the pneumatic transport of coarse grain particles (alumina) through a horizontal pipe is considered. Corresponding flow of the mixture is assumed as a two-phase one-dimensional flow. The present work considers a air mass balance model. A MATLAB program is developed to update the governing equations. Since a good agreement is observed between the present prediction and the result available in the literature, the model is used for further investigation. The variation of pressure drop, velocity and mass flow rate along the length of pipe for both low and high volume flow rate is predicted. It is observed that the pneumatic transport of the alumina particles is permitted up to a limiting length of the pipe due to a huge pressure drop in the pipe at very high velocity. Corresponding limiting length of the pipe with different mixture velocities is predicted.
Simulation of Propulsive Dynamics of an Organism in a Viscous Fluid Using an Immersed Boundary Finite Volume Method
Authors: Maniyeri Ranjith
Published: July 2014

Inspired by the propulsion of organisms in a viscous fluid, we develop a two-dimensional computational model to study the propulsive and fluid dynamic features of an organism modeled as an elastic filament in viscous fluid using immersed boundary (IB) finite volume method. The elastic filament is modeled using discrete number of IB points. The elastic forces are computed based on an elastic energy function. The Navier-Stokes equations governing the fluid flow are solved on a staggered Cartesian grid system using the fractional step based finite volume method. The computational model is validated by comparing the numerical simulation results pertinent to the swimming of an infinite with that of the existing analytical results. The interplay of propulsive and fluiddynamic features of the organism in the viscous fluid is well captured using the developed model.
Computation of Lattice Kinetic Scheme for Double-Sided Parallel and Antiparallel Wall Motion
Authors: Perumal D. Arumuga , Dass Anoop K.
Published: July 2014

This paper is concerned with the double-sided lid-driven cavity simulation of two-dimensional lattice kinetic scheme on the uniform lattice arrangement based on the standard lattice Boltzmann method. The double-sided lid-driven cavity problem has multiple steady solutions for some aspect ratios. However, for the double-sided square cavity no multiplicity of solutions has been observed for both the parallel and antiparallel motion of the walls. To validate this new lattice kinetic scheme, the numerical simulations of the double-sided square driven cavity flow at Reynolds numbers from 10 to 1000 are carried out. The Reynolds number effect on the flow structure is clearly manifested by the streamline patterns and velocity profiles. It is concluded that the present study in double-sided lid-driven cavity produces results that are in excellent conformity with earlier conventional numerical observations.
Transient Simulation of Flow Past Smooth Circular Cylinder at very High Reynolds Number Using OpenFOAM
Authors: Hosur Sangamesh M. , Ramesha D.K. , Basu Suman
Published: July 2014

Flow past a smooth circular cylinder at high Reynolds number (Re=3.6 x 106) which covers the upper-transition regime has been investigated numerically by using Open source Field Operation and Manipulation (OpenFOAM) package. OpenFOAM is a free, open source Computational Fluid Dynamics (CFD) software package. The numerical model has been set up as two dimensional (2D), transient, incompressible and turbulent flow. A standard high Reynolds number k-ε turbulence model is included to evaluate the turbulence. The objective of the present work is to set up the case using pimpleFoam solver which is an Unsteady Reynolds Averaged Simulations (URANS) model and to evaluate the model for its conformance with available literature and experiments. The results obtained are compared with experimental and numerical data.
Experimental Study on Effect of Vibratory Flap Position on Dynamic Response of Clamped Rectangular Plate with Cut-Out
Authors: Mahadevaswamy P. , Suresh B.S.
Published: July 2014

In structural applications, plates with cut-out or holes are commonly used. The structure will deteriorate dynamically due to presence of cut-out and experiences amplification in vibrations. This paper presents an experimental study on effect of position of vibratory flap on dynamic response of a clamped rectangular plate with cut-out subjected to harmonic excitation. Vibratory flap is an auxiliary plate attached on the main plate as a cantilever plate and acts as a dynamic vibration absorber, which is used to reduce the vibration of the plate at first and second frequencies. Investigation has been carried out for different combinations of flap location and orientation through experimental sine sweep test. From the test it is found that, there is an optimum position where vibration suppression is more effective with improved dynamic response of the plate with cut-out in the presence of flap. The experimental results have shown good agreement with the published finite element analysis results.
Free Vibration Analysis of a Carbon Nanotube Reinforced Composite Beam
Authors: Naresh B. , Babu A. Ananda , Sudhagar P. Edwin , Anisa Thaslim A. , Vasudevan R.
Published: July 2014

In this study, free vibration responses of a carbon nanotube reinforced composite beam are investigated. The governing differential equations of motion of a carbon nanotube (CNT) reinforced composite beam are presented in finite element formulation. The validity of the developed formulation is demonstrated by comparing the natural frequencies evaluated using present FEM with those of available literature. Various parametric studies are also performed to investigate the effect of aspect ratio and percentage of CNT content and boundary conditions on natural frequencies and mode shapes of a carbon nanotube reinforced composite beam. It is shown that the addition of carbon nanotube in fiber reinforced composite beam increases the stiffness of the structure and consequently increases the natural frequencies and alter the mode shapes.
Free Vibration Analysis of a Width Tapered Laminated Composite Beam
Authors: Chandrawanshi Aayush , Bhaiyat S. , Jain A. , Babu A. Ananda , Sudhagar P. Edwin , Vasudevan R.
Published: July 2014

A numerical investigation is performed to study the free vibration responses of a width tapered composite beam. The finite element simulation is performed to investigate the effect of taper angle along the longitudinal plane of the beam on the free transverse vibration responses. Experimental investigations are also performed to demonstrate the effectiveness of the developed finite element formulation (FEM) in identifying the free vibration responses of the uniform and tapered composite beam. Further, various parametric studies are performed to investigate the effect of taper angle and boundary conditions on natural frequencies of the uniform and tapered composite beams. It is shown that the natural frequencies of the taper configurations at all the modes considered are higher than those obtained from the uniform composite beam. It is concluded that the stiffness of the composite structures could be tailored according to the requirement by changing the taper angle of the composite along longitudinal plane to obtain the desired natural frequencies.
Free Vibration Characteristics of Metallic Propeller Blade Replaced with Composite Material Using Finite Element Approach
Authors: Kishore M.L. Pavan , Behera Rabindra K.
Published: July 2014

Structural vibrations problems presents a major hazard and design limitation for a wide range of engineering problems. A comprehensive study of vibration phenomena includes determining the nature and extent of vibration response levels. This paper focuses in determining suitability of composite material in replacement of metallic material for assessing the dynamic characteristics of the blade. This study reviews the natural frequencies and associated mode shapes for a pre twisted composite propeller blade for marine applications. MAB and composite are used .composite with symmetric and balanced stacking sequence were analyzed. From the results it can be concluded that by further changing the layup sequence composite materials can be made much stiffer than MAB propeller.
Effect of Filler Materials on the Mechanical and Thermal Properties of Epoxy Resin
Authors: Siva Sankari S. , Murugan N. , Sivaraj S.
Published: July 2014

In this present work the influence of Cenosphere filler material in thermal and mechanical properties of Epoxy resin is discussed. For comparative study, pure resin and composites made with different compositions (1, 3 and 5 wt% of Cenosphere) were prepared. The specimens were submitted to thermal analysis (DMA) and mechanical test (Tensile and Flexural) as well. Dynamic mechanical analysis (DMA) revealed an enhancement in the energy dissipation ability of the composite with 1wt%, wt3%, wt5% of Cenosphere and an increase in stiffness relative to the pure matrix phase. It was generally observed that the tensile strength found to increase with the inclusion of Cenosphere as filler material. Maximum value of tensile stress and strain of resin is not sensitively increased by filler material.