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Automotives play a very important role in day-to-day human lives. The exhaust gas emitted from automotive vehicles of current technologies is one of the major contributions to global temperature increment. It is important to develop a system that can conserve energy and incorporate it into current vehicles which are in use. Phase change materials (PCM) are well known for energy storage applications because of their crucial thermophysical property known as latent heat of fusion. The gas from the exhaust pipe of automobiles can be considered a turbulent jet. With this assumption in this study, a system is proposed by combining jet impingement and phase change material at the exhaust pipe of automobiles to recover the thermal energy which is being let out into the atmosphere as waste. Liquid Gallium is chosen as a phase change material for this study because of its high thermal conductivity nature compared to other hydrocarbon-based phase change materials.

Numerical simulation has been performed to study the heat transfer enhancement from the vertical heated wall surfaces with the help of rising bubbles due to the buoyancy force. The effect of wall proximity and bubble shapes are investigated for three wall shapes such as plane wall, wavy wall and triangular wall. Numerical solution is obtained by solving both the thermos-fluid governing equations and the Volume of Fluid (VOF) advection equation along with the Piecewise-Linear Interface Construction (PLIC) algorithm available in ANSYS-Fluent, an FVM based commercial CFD code. The results observed in the three types of wall geometries were showing the heat transfer differently for the 3 mm bubble. For the plane wall from the rise of the bubble to 0.3 seconds the temperature gradient is 10 K whereas for the curved and triangular wavy walls these gradients are 9.6 K and 17.23 K respectively. and after 0.6 seconds, this gradient is almost the same for all the wall shapes.

Recent years, researches are more focused on various enhancement methods for compact heat exchangers without altering the surface area of the heat exchangers. The advancements in the area of Nano fluids with better thermal properties have helped in development of light-weight, highly efficient automobile radiators. The main objective of this project is to increase the thermal performance of the radiator and thereby reducing the size of the radiator. In this project a numerical model with porous medium approach was developed and validated. Nano fluids (Aluminium oxide, Copper oxide, Graphite) of different volumes (ranging from 1%-13% in an interval of 2) are used along with water and it was observed that the heat transfer rate of the radiator is increased by 4.49% and the volume of the radiator is reduced by 5.4% for the addition of 5% of Aluminium oxide in water.

Heat transfer analysis in the combustion chamber of internal combustion engine is crucial to design the combustion chamber. Manufactures will always look for the durability, better engine performance and also on the material cost for designing the combustion chamber. This will be achieved by designing the efficient combustion chamber effectively. The purpose of this paper is to determine the Adiabatic Flame Temperature using stoichiometric equations and find the gas temperatures at different points in the ideal diesel cycle. These values are used in the existed heat transfer coefficient equations and estimate the heat transfer to the coolant through the cylinder wall using one dimensional heat equation. This theoretical value of heat transfer rate is compared with the experimental heat transfer rate of the three cylinder engine. The average error percentage of the theoretical and experimental values is less than the 15 %.

In the present work, it is aimed at developing an integrated approach for combustor modeling involving rapid prototyping and water tunnel testing to assess the cold flow numerical simulations; the physical model will be subjected to cold flow visualization and parametric studies and CFD analysis to demonstrate its capability for undergoing rigorous cold flow testing. A straight through annular combustors is chosen for the present study because of it has low pressure drop, less weight and used widely in modern day aviation engines. Numerical Analysis has been performed using ANSYS-FLUENT. Three dimensional RANS equations are solved using k-ɛ model for the Reynolds numbers ranging from 0.64 x 105-1.5 x 105 based on the annulus diameter. Post processing the results is done in terms of jet penetration, formation of recirculation zone, effective mixing, flow split and pressure drop for different cases.

A numerical study of three-dimensional flow and heat transfer of a rectangular plain with built-in delta winglet type longitudinal vortex generators is carried out in order to enhance the convective heat transfer at the air side of the fin with minimum penalty on pressure drop. Longitudinal vortices develop along the side edge of the delta winglets due to the pressure difference between the front surface (facing the flow) and back surface. These vortices interact with thermal boundary layer and produce a three dimensional swirling flow that mixes near wall fluid with the midstream. Thus the thermal boundary layer is disrupted and heat transfer is enhanced. The efficiency of the delta winglet vortex generators widely varies depending on their size and shape, as well as the locations where they are implemented. In the present study, the longitudinal vortices have been created by the delta-winglet type vortex generators in common-flow-down configuration.