bluuebunny/crossref_metadata_2025 huggingface dataset:
A new approach to hydraulic calculations of free-flow drainage systems
Authors: Kitaytseva Elena
Published: February 2018

The accuracy of hydraulic calculations is determined by the accuracy of the mathematical models inherent in their foundation. The results of calculations, obtained by different models, and differing from each other by 5-10% is considered identical. The present study examines classical ways of finding the Chezy formula that are used for calculations of free-flow pipelines. These formulas differ from each other not only in parameters but also in the form of the functional dependence. The equation, underlying the hydraulic calculations, is nonlinear. Its solution is possible only in the number of well-established methods. It offers numerical computing to find pipelines diameters and their filling, as well as the algorithm to realize it. It conducts numerical experiment to compare pipelines diameters and filling and flow velocities. It presents frequency characteristics to distribute the parameters under analysis. For a specific example, the difference of cost of pipes, the diameters of which was found using the various formulas for coefficient Chezy, was calculated.
Hemodynamics of Idealized Carotid Artery
Authors: Puritipati Chaitanya , Keri Varun , Kumar Nitesh
Published: February 2018

The behavior of blood during its flow in human arteries has always been a subject of keen interest. Flow parameters such as pressure, velocity and wall shear stress vary with changes mainly in the geometry of the artery. The work focusses on the variation of wall shear stress along the walls of an Idealized Carotid Artery. Simulations are carried out for both Newtonian and Non-Newtonian behavior of blood. In the Non-Newtonian flow, Carreau-Yasoda model is chosen for the calculations. Steady flow and Transient flow cases are also analyzed where the User Defined Function is interpreted for further calculations. It is observed that recirculation of flow occurs at a critical area in the geometry. The results obtained are compared with the numerical results of Eleyas Shaik. The Wall Shear Stress plots are found to be in close correspondence to those in the thesis.
Vibration based condition monitoring of rotating machinery
Authors: Senapaty Goutam , Sathish Rao U.
Published: February 2018

This project looks at the different maintenance philosophies and the importance of vibration analysis in predictive maintenance. Since most industries and plants make use of rotational equipment, vibration analysis plays a major role in detecting machine defects and developing flaws before the equipment fails and potentially damages other related equipment and to avoid unwanted breakdowns and downtime. Vibration analysis can help increase the lifetime of equipment when the faults are diagnosed at the right time. Vibration analysis of a rotating table top model is also done to show that some faults might exist even though they are not visible to the naked eye.
Topological and fractal aspects of the main hydraulic parameters
Authors: Lyapin Anton , Lyapin Valery
Published: February 2018

The traditional concept of wetted cross-section, wetted perimeter and hydraulic radius seems fairly simple and clear, especially in the case of smooth boundaries of the flow. However, for the rough boundary surface covered with randomly arranged roughness the definition of the wetted cross-section as a normal to all elementary streams becomes notably problematic. More controversial seems the concept of wetted perimeter. This issue is of particular importance for the beds with high-dimensional roughness for which the geometric dimensions of the flow and the roughness elements are of the same order. The article shows that topological features of the boundary surfaces for the natural channels allow definitely refer them to fractals. Further study of the bed roughness based on its fractal nature can form a new approach to methodological soundness of main hydraulic parameters and open up new opportunities for their description.
Haemodynamic study of Flow in concentric and eccentric stenosed carotid Artery
Authors: Khader S. M. Abdul , Pai Raghuvir , Kamath Ganesh , Zuber Mohammed , Rao V. R. K.
Published: February 2018

Study of flow through arteries is gaining importance in the recent times due to onset of several cardio-vascular diseases like atherosclerosis (block in artery), aneurysms (bulging of artery), hypertension etc. The application of CFD will be useful in demonstrating the underlying mechanism of flow past the diseased arteries. In the present study, initially an approximate eccentric and concentric 50% stenosed carotid model is generated in ANSYS 12.0 based on patient data obtained from ultrasound Doppler scan. Later the percentage of stenosis is increased to 60%, 70%, 80% and 90% in both the cases. A transient analysis has been performed for several pulse cycles in ANSYS FLOTRAN for various percentage cases. The results obtained from ECN and CCN cases are compared to observe the changes in flow behavior in the downstream of stenosis as compared with normal case. The formation of vortices and flow separation zone in downstream in eccentric case is higher than in concentric case. Comparison of results concludes that, with the increase in severity of stenosis, the flow changes abruptly causing an increase in velocity and WSS at throat region. The simulation results obtained agree well with clinically observed data and available literature.
Fabrication of samarium strontium aluminate ceramic and deposition of thermal barrier coatings by air plasma spray process
Authors: Baskaran T , Arya Shashi Bhushan
Published: February 2018

Thermal barrier coatings (TBC) with the metallic NiCrAlY bond coat are often used in many aircraft engines to protect superalloy components from high-temperature corrosion thereby to improve the life of gas turbine components. The search for new TBC material has been intensified in recent years due to lack of thermo-physical properties of conventionally used Yttria stabilized Zirconia (YSZ) TBCs. Recently, the rare earth containing Samarium Strontium Aluminate (SSA) based ceramic was proposed as a new TBC material due to its matching thermo-physical properties with the substrate. The present work focused on the synthesis of SSA ceramics for TBCs application and its coatings development on Ni-based superalloy Inconel 718 substrate by air plasma spray process. The X-ray photoelectron spectroscopy (XPS) result confirmed the formation of single phase SSA ceramic after synthesis. The surface morphology of SSA TBCs is mainly composed of melted splats, semi and un-melted particles. The cross-sectional SEM micrographs did not show any spallation at the interface which indicated good mechanical interlocking between the bond coat and ceramic top coat. The Young’s modulus and hardness of SSA TBCs were found to be 80 and 6.1 GPa, respectively. The load-depth curve of SSA TBC showed good elastic recovery about 47 %.
Experimental Studies on SiC and Rice Husk Ash Reinforced Al Alloy Composite
Authors: Shivaprakash Y. M. , Sarkar Anunoy , Jha Sunit , Singh Muktesh , Bangera Shachin
Published: February 2018

In this research work Aluminium alloy with Cu (4.5%) as the major alloying element is used as the matrix in which SiC and Rice Husk Ash (RHA) are dispersed to develop a hybrid composite. The dispersion is done by the motorized stir casting arrangement. The composite is fabricated by varying the proportions of the reinforcements in the base alloy. The composite specimens were tested for density changes, hardness and the wear. The microstructure images showed a uniform dispersion of the reinforcements in the matrix and this resulted in higher strength to weight ratio. The increase in strength of the composite is probably attributed to the increase in the dislocation density. Also, the abrasive wear resistance of the produced composite is found to be superior as compared to the matrix alloy because of the hard-ceramic particles in the reinforcements.
Effect of SiC Nano powder on Multiaxial Woven and Chopped Randomly Oriented Flax/Sisal Fiber Reinforced composites
Authors: Kalagi Ganesh R. , Patil Rajashekar , Shetty Sunil Kumar , Nayak Madhukara
Published: February 2018

A study has been carried out to investigate effect of SiC Nano powder on tensile and impact properties of Multiaxial layers of Flax and Sisal fiber reinforced composites and randomly oriented chopped Flax and Sisal fiber reinforced composites. It has been observed that tensile strength and impact strength were improved using 6% of SiC Nanopowder into Multiaxial layer (+45º/-45º, 0º/90º) of Flax and Sisal where as randomly oriented chopped Flax and Sisal fiber reinforced composites are improved in its stiffnes for the same composition of fiber, epoxy and SiC Nano powder. SEM Analysis are done to analyse the distribution of SiC in both Multiaxial layers of Flax and Sisal fiber reinforced composites and randomly oriented chopped Flax and Sisal fiber reinforced composites.
Mechanical characterization of precipitation hardened Al7075-grey cast iron powder reinforced metal matrix composites
Authors: Hindi Jamaluddin , Achuta Kini , Amar Murthy
Published: February 2018

Al7075 alloy is the most commonly used by the aerospace industry. Al7075 alloy is characterized by its improved properties such as higher toughness, specific strength and hardness. The current work focuses on the preparation and characterization of age hardened Al7075-Grey cast iron composites. Two stage stir casting technique is used for the preparation of the composite. Age hardening treatment is imparted to enhance the mechanical characteristics. The variation of hardness and tensile strength with respect to aging temperature and percentage of reinforcement is analyzed. The composites exhibit higher hardness and tensile strength as the reinforcement percentage is increased at an aging temperature of 100°C.
Sliding wear studies of microwave clad versus unclad surface of stainless steel 304
Authors: Akshata M. K. , Hebbale Ajit M. , Srinath M. S.
Published: February 2018

Small and large scale (gas power plant, hydro power plant), automobile industries are suffering by failure of component. Sometimes, it is also observed that the component which was failed due to these reasons are very much costly and replacement of those also very difficult due to the complex geometry. By using Microwave hybrid heating, WC-12Co based clads were developed on austenitic stainless steel (SS304). Microwave clads were developed by introducing the preplaced, preheated powder for a duration of 15 min to microwave radiation at 2.45GHz frequency and 900 W power in domestic microwave applicator. By using optical microscope and scanning electron microscope (SEM), the developed clads were characterized. By using pin-on-disk, wear performance of the WC-12Co based clads and unclad samples were tested. It is observed that developed clad samples performed superior wear resistance than unclad samples.
Influence of post curing on GFRP hybrid composite
Authors: Chavan Vithal Rao , Dinesh K. R. , Veeresh K. , Algur Veerabhadrappa , Shettar Manjunath
Published: February 2018

Composite materials for the most part depicted as the mixes of two or more materials that outcome in the unmistakable properties than that of guard materials. Fibre strengthened plastics have been all around utilized for get-together flying machine and transport key parts as a delayed consequence of their specific mechanical and physical properties, for example, high particular quality and high particular robustness. Another pertinent application for fibre maintained polymeric composites (particularly glass fibre strengthened plastics) is in the electronic business, in which they are utilized for passing on printed wiring sheets. The utilization of polymer composite materials is winding up being powerfully essential. The present work delineates the change and mechanical portrayal of new polymer composites including glass fibre fortress, epoxy and maple cellulose fibre. The starting late made composites are delineated for their mechanical properties. The composite spreads were set up by utilizing hand layup framework. The experiments were conducted on and studied the effect of post curing on hybrid composites. The result reveals that the samples only with natural fibre have more promising results compared with synthetic fibre. The synthetic fibres get wrinkled due to post curing were as no such visuals in the natural fibres.
Case study on water based cellulose couplant in contact type ultrasonic testing
Authors: Shivamurthy B. , Krishnamurthy  , Sachidanada H. K.
Published: February 2018

In this paper the ultrasonic test performance of water based Methylcellulose couplant on steel is reported. The couplant used in the ultrasonic testing has an influence on the amplitude of the pulse echo signal. The ultrasonic energy which is transmitted from the transducer to the test material, through the couplant which is present in the interface. The amplitudes of back wall echo increases with increasing acoustic impedance of the couplant. In this research work couplant was prepared by using 0 to 50g of methylcellulose in steps of 10g in 250 ml of water. All five types of water based methylcellulose couplant were used for testing a standard stainless steel calibration U2 block. The effect on the amplitudes of back wall echoes was studied and best possible combination of water and methylcellulose are reported.
Sedimentation of suspended solids in ultrasound field
Authors: Vikulina Vera , Vikulin Pavel
Published: February 2018

Physical and chemical effects of aquatic environment that occur in an ultrasonic field change the sedimentation rate of coagulated suspension. This might only happen in case of cavitation of ultrasonic filed that causes a change of potentials of the medium. Research of the influence of ultrasonic vibrations on coagulation of suspended solids within water purification allows expanding their scope of implementation. The objective of the research is to estimate the effect of ultrasound on the sedimentation of the suspended solids, to determine of the efficiency of the process in relation to the dose of the coagulant, and to calculate the numerical values of the constants in the theoretical equation. The experiment condition was held in the water with the clay substances before the introduction of the coagulant. The method of magnetostriction ultrasonic generator was applied to receive ultrasonic vibration. Estimate of concentration of clay particles in water was performed using photometry. As a result of the research, the obtained data allow determining the increase in efficiency of suspended particles sedimentation related to the dose of coagulant, depending on time of ultrasonic treatment. The experiments confirmed the connection between the effect of sedimentation in the coagulation process, the coagulant dose and the time of scoring. Studies have shown that the increase in the duration of ultrasonic treatment causes a decrease of administered doses of coagulant.
A Review on Adsorption of Cationic Dyes using Activated Carbon
Authors: Corda Nikita Chrishel , Kini M. Srinivas
Published: February 2018

In this article efficiency of activated carbon as a potent adsorbent of cationic dyes has been reviewed. Non-biodegradable nature of pollutants and their removal in the present generation is a great challenge. Therefore, extensive study on adsorption of these classes of pollutants from water bodies is being carried out. Methylene blue (majorly) a dye seen in the effluent streams of textile, printing, paper industries along with some of the commonly used cationic dyes in process industries and their sorption on activated carbon are reviewed here. High cost of commercially activated carbon which is a limitation to its extensive use have paved way for study of adsorption by naturally obtained and extracted activated carbon from agricultural wastes and various other sources. The purpose of this review paper is to summarize the available information on the removal of cationic dyes using naturally extracted and commercially obtained activated carbon. Various parameters such as temperature, initial dye concentration, pH, contact time, adsorbent dosage, particle size, stirring, agitation etc. were studied and the optimum parameters were determined based on the experimental outcomes. Equilibrium data was examined using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich and few other isotherm models. Kinetic studies also have been carried out to find the most suitable way of expressing the adsorption process.
Influence of Sawdust Bio-filler on the Tensile, Flexural, and Impact Properties of Mangifera Indica Leaf Stalk Fibre Reinforced Polyester Composites
Authors: Heckadka Srinivas Shenoy , Nayak Suhas Yeshwant , Gouthaman P. V. , Talwar Abhishek , Ravishankar V. A. , Thomas Linto George , Mathur Ankur
Published: February 2018

The need to have biodegradable composites is aloft in today’s market as they are environment friendly and are also easy to fabricate. In this study, mangifera indica leaf stalk fibres were used as reinforcement along with saw dust as bio-filler material. Unsaturated isophthalic polyester resin was used as the matrix. The fibres were treated with 6 % vol. NaOH and neutralized with 3 % vol. of dilute HCl. Treatment of sawdust fillers was done by using 2% vol. NaOH solution. Hand layup method and compression moulding technique was used to fabricate the composite laminates. Specimens for evaluating the mechanical properties were prepared by using water jet machining. The results indicated an increase in tensile, flexural and impact strength of composites with addition of sawdust upto 3%. Further addition of the bio-filler resulted in decrease of mechanical properties.
Tensile and Flexural Properties of Chopped Strand E-glass Fibre Mat Reinforced CNSL-Epoxy Composites.
Authors: Nayak Suhas Yeshwant , Heckadka Srinivas Shenoy , Thomas Linto George , Baby Anil
Published: February 2018

Glass fibres have the principal advantages such as high tensile strength, high chemical resistance, low cost, and excellent insulating properties which makes them an important constituent in fibre reinforced plastic and composite industry. In this study, E-glass fibre in the form of Chopped Strand Mat (CSM) with different weight fractions such as 15%, 30%, and 45% were used as reinforcement in CNSL-epoxy resin composites. Fabrication of the composites was done by hand layup technique. Micro-hardness, tensile and flexural properties were investigated for all the composite panels of different compositions. The results clearly indicated an improvement in micro hardness, tensile and flexural properties with the increase in fibre content.
Influence of plasma modification on mechanical and thermal properties of Polypropylene/ Nano-Calcium Silicate Composites
Authors: Ajeesh. G , Raman Aditya , Parameswaran Adarsh , Pandiyan Sundhara , Parvathy S. , George Philip
Published: February 2018

The aim of the research is to study the influence of plasma modification on nano calcium silicate/polypropylene composites. Polypropylene (PP) is considered for this study as it possesses high impact strength, toughness and availability. Calcium silicate is considered as reinforcement because of its high temperature resistance, high flexural strength and high strength to mass ratio. Fourier transform infrared spectroscopy (FTIR) results show that there is a change in the functional group on the surface of calcium silicate after modification. Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) results show that the decomposition temperature increased with increasing amount of filler particles. It is also observed that the modification has produced a marginal increase in the decomposition and glass transition temperature. Tensile test results also show a gradual increase in the tensile properties of composites when high ratio is reinforcement. Tensile test results also show that there is a marginal increase in the tensile strength when reinforced with modified calcium silicate when compared to non-modified. Scanning Electron Microscopy (SEM) reveals that there is a enhanced dispersion of nano particles on modification. Based on the findings it can be concluded that plasma modification enhances the thermal and mechanical property marginally.
Machinability study of Al-TiC metal matrix composite
Authors: Siddappa P. N. , Shivakumar B. P. , Yogesha K. B. , Mruthunjaya M. , Hanamantraygouda M. B.
Published: February 2018

Aluminum Metal Matrix Composites have emerged as an advanced class of structural materials have a combination of different, superior properties compared to an unreinforced matrix, which can result in a number of service benefits such as increased strength, higher elastic moduli, higher service temperature, low CTE, improved wear resistance, high toughness, etc. The excellent mechanical properties of these materials together with weight saving makes them very attractive for a variety of engineering applications in aerospace, automotive, electronic industries, etc. Hence, these materials provide as alternative substitutes for conventional engineering materials when specific mechanical properties necessary for required applications. In this work an attempt is made to study the machining parameters of Al6061/TiC MMC. The composite is developed by reinforcing TiC particles in varying proportions of 3, 6, 9 and 12 % weight fractions to the Al6061 matric alloy through stir casting technique. Cutting forces were measured by varying cutting speed and feed rate with constant depth of cut for different % weight fractions. The results showed that the cutting force increases with the increase of feed rate and decreases with the increase of cutting speed for all the weight fractions. Cutting parameters were optimized using Taguchi technique.
Friction stir welding of Aluminium matrix composites – A Review
Authors: Subramanya Prabhu , Amar Murthy , Arun Shettigar , Mervin Herbert , Shrikantha Rao
Published: February 2018

Friction stir welding (FSW) is established as one of the prominent welding techniques to join aluminium matrix composites (AMCs). It is a solid state welding process, takes place well below the melting temperature of the material, eliminates the detrimental effects of conventional fusion welding process. Although the process is capable to join AMCs, challenges are still open that need to be fulfill to widen its applications. This paper gives the outline of the friction stir welding technique used to join AMCs. Effect of process variables on the microstructure and mechanical properties of the joints, behavior of reinforcing materials during welding, effect of tool profiles on the joint strength are discussed in detail. Few improvements and direction for future research are also proposed.
Performance improvement studies for cutting tools with perforated surface in turning of titanium alloy
Authors: Charitha Rao , Shrikantha Rao , Mervin Herbert
Published: February 2018

In turning process, the cutting tool is essential for shaping materials. The cutting tools with various perforated surfaces help to increase the cutting tool life. Also, advances in CNC machining technologies have enhanced the productivity of machining process. One of the best or futuristic approaches in modern manufacturing engineering is the use of FEM Simulation for the metal cutting process. FEM simulation helps in understanding the metal deformation process and also helps in the reduction of experiments. The simulation helps the researchers to predict the major influencing cutting variable values without carrying out any experiment which is time-consuming and expensive. This research presents the simulation study of the performance of micro-hole patterned Polycrystalline Diamond cutting insert in machining Titanium alloy (Ti-6Al-4V). Micro-holes are drilled using Electrical Discharge Wire Drilling machine on the rake face of Polycrystalline Diamond (PCD) cutting inserts. FEM analysis is carried out to evaluate the effect of perforations on the mechanical integrity of insert. The micro-hole patterned insert is modeled in PRO-E modeler and simulated using DEFORM-3D software. The effective stress, strain, and temperature distribution are analyzed and the results are compared with the normal insert.
Optimize the Rolling Process Parameters for Material AA1100 using Metal Forming Simulation
Authors: Hemanth T. S. , Arunkumar Y. , Srinath. M. S.
Published: February 2018

Metal forming plays a very important role in the manufacturing. Simulation of manufacturing process aids in the improvement of quality, reduce energy and resource consumption and helps in visualization of the process. The design of experiment helps in optimization of the parameters in any processes. In this paper, Taguchi optimization technique is used to predict the best results for the given inputs such as roller diameter, friction value, velocity of the rollers and percentage reduction to the forming process and get the optimized values for spread, hardness, effective stress, power required, strain rate and torque using the manufacturing simulation software. It is found that the important parameter is percentage reduction affecting the effective stress. Optimal parameters with desirability value of 0.87 have been obtained.
Surface roughness optimization in machining of AZ31 magnesium alloy using ABC algorithm
Authors: Abhijith  , Srinivasa Pai , Grynal D’Mello , Gautama Hebbar
Published: February 2018

Magnesium alloys serve as excellent substitutes for materials traditionally used for engine block heads in automobiles and gear housings in aircraft industries. AZ31 is a magnesium alloy finds its applications in orthopedic implants and cardiovascular stents. Surface roughness is an important parameter in the present manufacturing sector. In this work optimization techniques namely firefly algorithm (FA), particle swarm optimization (PSO) and artificial bee colony algorithm (ABC) which are based on swarm intelligence techniques, have been implemented to optimize the machining parameters namely cutting speed, feed rate and depth of cut in order to achieve minimum surface roughness. The parameter Ra has been considered for evaluating the surface roughness. Comparing the performance of ABC algorithm with FA and PSO algorithm, which is a widely used optimization algorithm in machining studies, the results conclude that ABC produces better optimization when compared to FA and PSO for optimizing surface roughness of AZ 31.
Study of mould hardness for alpha set type resin bonded moulding sand system using Taguchi approach for metal casting applications
Authors: Anand Deshpande , Aishwarya Gharge , Pratik Deshpande , Pratik Patil , Tejashree Vaidya , Ganesh Chate
Published: February 2018

The quality of the castings are depended on many properties of sand mould like mould hardness, green compression strength, shear strength etc. and these properties in turn dependent on factors such as grain fineness number of sand, setting/curing time, amount of resin, amount of hardener, moisture content etc. Mould hardness is very important while transferring mould from moulding station to pouring station when the weight of the mould is above 100kg and may lead to defects. In the present work, an effort is made to study the mould hardness of a moulding sand specimen using Taguchi technique.L9 orthogonal array is used and experiments are conducted randomly. The main factors such as the amount of resin, amount of hardener and setting time were considered. Factors were selected based on Literature review and brainstorming session with foundries. The chemical (resin and hardener) used is alphas set type two part system. From experiments, it was observed that the Amount of resin and setting time are significant for mould hardness. Confirmation tests were conducted to validate the obtained results.
Effect of variable thermal conductivity on entropy generation in a plate with internal energy generation
Authors: Favas T. K. , Jilani G.
Published: February 2018

The current numerical investigation aims at analyzing the effect of variable thermal conductivity on local and global entropy generation rates in an energy generating plate dissipating heat by conjugate conduction-forced convection heat transfer. In order to fulfill this objective, the physical model of the plate dissipating heat into surrounding coolant is transformed into a mathematical model governing the temperature field in the plate as well as flow and thermal fields in the fluid. The resulting mathematical model, being a set of coupled and non linear partial differential equations, is solved by adopting stream function-vorticity formulation and by employing Alternating direction implicit scheme. Keeping Prandtl number of the fluid, temperature of the free stream coolant and maximum permissible plate temperature as fixed, numerical predictions are obtained for wide range of values of aspect ratio, conduction-convection parameter, energy generation parameter and flow Reynolds number. It is concluded that unrealistic constant thermal conductivity assumption leads to underestimation of entropy generation rates. It is also found that an increase in energy generation parameter results in significant increase in underestimation of global entropy generation rate.
Design and Simulation of a Vapour Compression Refrigeration System Using Phase Change Material
Authors: Siddharth Raju , Jagannath Korody , Kini Giridhar P. , Vishnumurthy K. Kedlaya
Published: February 2018

The paper details the design and simulation of a solar powered vapour compression refrigeration system. The effect of a phase change material, in this case ice, on a vapour compression refrigeration system powered by solar panels is discussed. The battery and solar panels were sized to allow the system to function as an autonomous unit for a minimum of 12 hours. It was concluded that the presence of a phase change material in the refrigeration system caused a considerable increase in both the on and off time of the compressor. The ratio by which the on time increased was greater than the ratio by which the off time was increased. There was a 219% increase in the on time, a 139% increase in the compressor off time and a 3.5% increase in compressor work accompanied by a 5.5% reduction in COP. Thus, under conditions where there is enough load in the system to cause the initial on and off times of the compressor to be comparable, the presence of a phase change material may result in a greater on period than an off period for the compressor.
Thermoacoustic Refrigerator for High Temperature Gradient
Authors: Mishra Abhishek , Choudhary Ankur Kumar , Tomar Taniya , Korody Jagannath
Published: February 2018

Leakage of HFCs, thermal shocks to sensitive devices, moving mechanical components which in turn require more maintenance, are some of the cons of a conventional vapor compression system .The newest field in refrigeration overcoming such flaws is Thermoacoustic refrigerator (TAR), where the sound energy is used to generate a temperature difference which can be used for refrigeration. TAR are environment friendly, do not use any kind of refrigerants, and as the compressor and expander are not used, hence, its life is more than a conventional VCR. The objective is to obtain a substantial temperature gradient using a Thermoacoustic Refrigerator. The methodology is to choose the suitable material and design the prototype. A large part of this project is devoted to explore the different designs for thermo acoustic refrigerators, and select the optimum one for maximum utility. With the present system, it was possible to achieve a temperature difference across the stack of 14 K.
Performance analysis of PV panel under varying surface temperature
Authors: Kumar Tripathi Abhishek , Murthy Ch. S. N , Mangalpady Aruna
Published: February 2018

The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1°C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1°C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/°C.
Performance Testing of Diesel Engine using Cardanol-Kerosene oil blend
Authors: Ravindra  , Aruna M , Harsha Vardhan
Published: February 2018

Awareness of environmental pollution and fossil fuel depletion has necessitated the use of biofuels in engines which have a relatively cleaner emissions. Cardanol is a biofuel, abundantly available in India, which is a by-product of cashew processing industries. In this study performance of raw Cardanol blended with kerosene has been tested in diesel engine. Volumetric blend BK30 (30% kerosene and 70% Cardanol) has been used for the test. The properties like flash point, viscosity and calorific value of the blend have been determined. The test was carried out in four stroke diesel engine connected with an eddy current dynamometer. Performance of the engine has been analysed by finding the brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE). The results showed that the brake thermal efficiency of the blend is 29.87%, with less CO and smoke emission compared to diesel. The results were also compared with the performance of Cardanol diesel blend and Cardanol camphor oil blend, which were already tested in diesel engines by other researchers. Earlier research work reveals that the blend of 30% camphor oil and 70% Cardanol performs very closer to diesel fuel with a thermal efficiency of 29.1%. Similarly, higher brake thermal efficiency was obtained for 20% Cardanol and 80% diesel blend.
Performance computation of window air conditioner with very low GWP near azeotropic refrigerant mixtures as a drop in Substitutes to R22
Authors: Vali Shaik Sharmas , Setty Talanki Puttaranga , Babu Ashok
Published: February 2018

The principal objective of the present study is to compute the thermodynamic performance of window air conditioner based on standard vapour compression refrigeration cycle using R22, R407C and nineteen refrigerant mixtures. In this work nineteen R290/R1270 blends at different compositions are developed. A MATLAB code is developed to compute the thermodynamic performance parameters of all the studied refrigerants at condensing and evaporating temperatures of 54.4°C and 7.2°C respectively. The performance parameters are cooling effect, compressor work, COP, compressor discharge temperature, power per ton of refrigeration and volumetric cooling capacity respectively. Analytical results revealed that COP of new binary mixture R290/R1270 (90/10 by mass %) is 2.82% higher among R22, R407C and nineteen studied refrigerants. Energy required by the compressor per ton of refrigeration for R290/R1270 (90/10 by mass %) is 2.73% lower among R22, R407C and nineteen studied fluids. The discharge temperature of the compressor for all the nineteen investigated blends are reduced by 6.0-8.9oC compared to R22. Overall thermodynamic performance of window air conditioner with R290/R1270 (90/10 by mass %) is better than R22 with significant savings in energy consumption and hence it is an energy efficient ecofriendly refrigerant mixture as a drop in substitute to R22.
Effect of Various External Shading Devices on Windows for Minimum Heat Gain and Adequate Day lighting into Buildings of Hot and Dry Climatic Zone in India
Authors: Kirankumar Gorantla , Saboor Shaik , Talanki Setty Putta Ranga , Babu Ashok
Published: February 2018

Glass is the major component of the building envelope to provide visual comfort to inside the buildings. In général clear and bronze glass was used as a main building envelope for both residential and commercial buildings to provide better day lighting into the buildings. If we use more glass area as a building envelope more radiation allows into the buildings. So that it is necessary to reduce more solar radiation and provide sufficient daylight factor inside the building's through glass windows with the help of external devices called shading devices. In this work four shading devices was tried on bronze glass window to find the heat gain and daylighting into buildings. This paper presents the experimental measurement of spectral characteristics of bronze glass which include transmission and reflection in entire solar spectrum region (300nm-2500nm) based on ASTM standards. A MATLAB code was developed to compute visible and solar optical properties as per the British standards. A building model was designed by design builder software tool. 40% window to wall ratio was considered for building models, thermal and day lighting analysis of buildings through windows was carried out in Energy plus software tool for hot and dry climatic zone of India.
Experimental and numerical investigation of heat dissipation from an electronic component in a closed enclosure
Authors: George Bobin Saji , Ajmal M. , Deepu S. R. , Aswin M. , Ribin D. , Akhil J.
Published: February 2018

Intensifying electronic component power dissipation levels, shortening product design cycle times, and greater than before requirement for more compact and reliable electronic systems with greater functionality, has heightened the need for thermal design tools that enable accurate solutions to be generated and quickly assessed. The present numerical study aims at developing a computational tool in OpenFOAM that can predict the heat dissipation rate and temperature profile of any electronic component in operation. A suitable computational domain with defined aspect ratio is chosen. For analyzing, “buoyant Boussinesq Simple Foam“ solver available with OpenFOAM is used. It was modified for adapting to the investigation with specified initial and boundary conditions. The experimental setup was made with the dimensions taken up for numerical study. Thermocouples were calibrated and placed in specified locations. For different heat input, the temperatures are noted down at steady state and compared with results from the numerical study.
Numerical Analysis of Heat transfer Enhancement in a double pipe heat exchanger with a holed twisted tape
Authors: Kumar Akarsh , Sureka Ujjawal , Kumar Shiva
Published: February 2018

In the present study numerical analysis of enhancement in heat transfer characteristics in a double pipe heat exchanger is studied using a holed twisted tape.The twisted tape with a constant twist ratio is inserted in a double pipe heat exchanger. Holes of diameter 1mm, 3 mm and 5 mm were drilled at regular pitch throughout the length of the tape. Numerical modeling of a double pipe heat exchanger with the holed twisted tape was constructed considering hot fluid flowing in the inner pipe and cold fluid through the annulus.Simulation was done for varied mass flow rates of hot fluid in the turbulent condition keeping the mass flow rate of cold fluid being constant. Thermal properties like Outlet temperatures, Nusselt number, overall heat transfer coefficient, heat transfer rate and pressure drop were determined for all the cases. Results indicated that normaltwisted tape without holes performed better than the bare tube. In the tested range of mass flow rates the average Nusselt number and heat transfer rate were increased by 85% and 34% respectively. Performance of Twisted tape with holes was slightly reduced than the normal twisted tape and it deteriorated further for higher values hole diameter. Pressure drop was found to be higher for the holed twisted tape than the normal tape.
Augmentation of Effective Thermal Gain of Solar Air Heater using a Novel Turbulator Design- A CFD Study
Authors: Dhagat Animesh , Manjunath M. S.
Published: February 2018

Augmentation of thermal performance of solar air heater has been the focus of many researchers over the last decades and the use of turbulator or artificial roughness to provide increased fluid mixing in order to achieve augmented heat transfer has been a widely accepted technique. This work aims to evaluate the effect of a novel turbulator design on the effective thermal performance of solar air heater using the methodology of computational fluid dynamics (CFD). A two dimensional CFD analysis is carried out to evaluate the thermal characteristics of solar air heater at various flow Reynolds number conditions for different geometric parameters of the proposed turbulator design. The pitch of the turbulator is varied as 10mm, 20mm, 30mm, 40mm and 50mm for a fixed turbulator height of 2 mm. The Reynolds number is varied from 6,000 to 27,000. The analysis shows that the lower values of pitch produces higher improvement in heat transfer. The maximum increase in Nusselt number is found to be about 2.98 times as compared to the base model for the flow Reynolds number of about 6000. The highest increase in the friction factor is found to be about 3.05 times relative to the base model. The maximum thermal enhancement factor is found to be about 1.99 for the pitch value of 10 mm at a flow Reynolds number of about 6000.
Vortex dynamics and elliptical structure wake interaction in the proximity of wall using 2-D RANS simulation
Authors: Arunkumar H. S. , Mangrulkar Chidanand , Gohil Trushar
Published: February 2018

The 2-D numerical study is performed to analyses the flow characteristic behind the elliptical structure placed near the wall for three different gap ratios as 0.25, 0.5, and 1.0. Computational domain and model is initially validated with the unbounded flow over a cylinder without considering wall effect for Reynolds number of 3900. For flow over the cylinder with near wall, computational domain is modelled as Blasius profile is the input to the area of interest. At different gap ratios the effect of boundary layer on vortex shedding is studied with Reynolds number of 1440. By applying different turbulent model for analysis, study the variation in the results and suggest the suitable model for the present type of study. It has been observed that the wall effect is predominant in case of the gap ratio of 0.25 as compared to other gap ratios.
Ways of heat losses reduction in the structural elements of unique buildings
Authors: Kochev Alexey , Lushin Kirill , Sokolov Mikhail , Kocheva Elena , Kocheva Marina
Published: February 2018

In this article the results of theoretical and experimental studies of the reduction of heat losses in the elements of external enclosing structures of under construction, reconstructed, reconstructed and currently operated unique buildings (monuments of history and architecture) presents.
Fabrication and performance analysis of concentrated hybrid photovoltaic system
Authors: Murthy Krishna , Daniel Ajay , Concessao Lanvin , Roy Habbie Alex , Ganesha A.
Published: February 2018

Sun is the most important source of renewable source of energy. During the past few decades there has been an ever-increasing interest in Photovoltaic (PV) cells as it directly converts solar radiation into electricity. This paper involves the performance study of photovoltaic system under concentrated solar radiation. The main problem with the concentration solar energy is the drastic increase in temperature of the photovoltaic module resulting in a decrease in performance efficiency of the system. This problem of overheating of the system can be overcome by providing cooling which would ensure operation of the module in the optimal temperature range. Hence, the setup would function as a hybrid model serving the dual purpose of power generation while also utilizing the waste heat for water heating applications. The experimental set up consist of a novel arrangement of concentrator and reflector and the cooling system. The Hybrid Photovoltaic System was repeatedly tested under real time conditions on several days. A comparison was drawn between the results obtained from direct exposure of a standard photovoltaic module to that obtained from the hybrid system in order to better understand the improvement in performance parameters. The study shown a significant improvement of output of standard photovoltaic module under the concentrated solar radiation.
Reliability Assessment and Study of Quality Control Tools on Intermixer and Dump Mill of a Tyre Manufacturing Industry
Authors: Prashanth Pai M. , Ramachandra C. G. , Srinivas T. R. , Raghavendra M. J.
Published: February 2018

Quality plays a very important role in today's highly competitive industrial environment. Quality leads to an improvement in the productivity. Quality control tools are used to solve more than 90% of the problems faced by the organizations in improving its effectiveness and meeting the customer expectation on a continuous basis. The success of the quality control procedure depends greatly on the method of data collection and its accuracy. Quality control tools are used worldwide in manufacturing industries for continual improvement and are implemented in different steps of manufacturing process to define the problem, measure its impact, finding out its root cause and its removal to ensure the production of non-defective items. The present work includes collection of failure data of intermix and dump mill of a tyre manufacturing unit located in Karnataka. The failure data collected for one year has been analysed to find out the major causes of breakdown. Quality control tools such as Pareto chart, Bar chart, Histogram, Fish bone diagram have been used to find out the root causes and identifying the action plans to eradicate them. Reliability assessment (theoretical) of intermix and dump mill has been conducted using the failure data. The reliability and maintainability curves speak about the present state of working of maintenance department in regard to addressing of breakdown problems and also help in setting future working standards.
Success of manufacturing industries – Role of Six Sigma
Authors: Venkatesh N. , Sumangala C.
Published: February 2018

Six Sigma is a phenomenal quality management concepts which has helped many organizations to overcome quality crisis in the recent past. Six Sigma is observed as a very promising quality management tool for any organization to make its presence felt in the corporate world as it emphasizes on obtaining a fruitful solution to improve accuracy, reduce defect thereby reduce the cost and improve profits. The main objective of this investigation is to unearth the extent to which the companies have been benefitted due to Six Sigma implementation. This article presents the results based on the analysis of collective opinion of employees of various Indian manufacturing industries that have implemented Six Sigma. This research also examines interrelationship among various parameters defined in the research. The research revealed that industries are benefitted irrespective of their nature in terms of their growth, financial benefits, productivity and satisfaction of the customer. However, peoples’ equity that deals with the benefits that employees obtain after Six Sigma implementation is not certain. The research also revealed the existence of strong interrelationship among various parameters used to measure the success of Six Sigma.
Study of a supply chain system with the presence of bullwhip effect
Authors: Shrivastava Ayush , Kamath Raghavendra , Sharma Himanshu , Gogoi Ajitesh
Published: February 2018

A study has been conducted to understand the effect of bullwhip phenomenon in a supply chain system. The hypothetical data collected from the study is used to make a model which can be used to simulate the operation of the system with moderate complexity. System dynamics approach is used to create an open loop system. The phenomenon used is slightly modified and empirically analysed to bring down its adverse effect on the system. The results obtained graphically are emphasising the effect of bullwhip on the various levels of the supply chain system.