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Abbreviations e Eccentricity between shaft and bearing, m C Radial clearance, m R Radius of the shaft, m h Film thickness, m ω Angular velocity, rad/sec W Load carrying capacity, N O' Bearing centre O Shaft centre ρ Fluid density, kg/m 3 ρ l Liquid density, kg/m 3 ρ v Vapor density, (kg/m 3) v Fluid velocity P Static pressure, Pa τ Stress tensor F External body force, N t Time ε Eccentricity ratio σ Liquid surface tension coefficient v Fluid velocity vector C e , C c Mass transfer source terms connected to the growth and collapse of the vapor bubbles, respectively F cond Condensation coefficient F evap Evaporation coefficient p v Saturation pressure of the fluid [M s ] Structural mass matrix [M f ] Fluid mass matrix [F s ] Structural force matrix [F f ] Fluid force matrix [R] Coupling matrix Δh Relative rigid displacement of the two bearing surfaces δ Total elastic deformation of the shaft and bearing system Abstract This work deals with a study of a three-dimensional CFD analysis and multi-phase flow phenomena for hydrodynamic journal bearing with integrated cavitation. The simulations are carried out considering the realistic bearing deformations by two-way fluid-structure interactions (FSI) along with cavitation using ANSYS ® Workbench software. The design optimization module is used to generate the optimized solution of the attitude angle and eccentricity for the combination of operating speed and load. Bearings with and without cavitation are investigated. A drop in maximum pressure value is observed when cavitation is considered in the bearing. The rise in oil vapor distribution is noted with an increase in shaft speed which lowers the magnitude of the pressure build up in the bearing. The bearing deformations are analyzed numerically and found increasing with an increase in shaft speed. The experimental data obtained for pressure distribution showed good agreement with numerical data along with a considerable reduction in computation time.

This work focusses on a novel technique of producing bioethanol from fermented pomegranate fruits waste by using Saccharomyces cerevisiae , commonly known as baker's yeast. Four different blends of bioethanol, namely PE10, PE15, PE20, and PE25 were experimented at various operating speeds. It was inferred that the addition of ethanol enhanced the consumption of fuel as well as braking capacity. However, thermal performance was observed to be declined. PE15 blend exhibited optimum brake thermal efficiency at full load condition when compared with unleaded fuel. Brake specific fuel consumption of PE15 was noticed to be lower at different operating speeds among all the blends. Oxides of nitrogen as well as carbon dioxide emissions were increased as the proportion of ethanol in pure fuel was increased. Hydrocarbon and carbon monoxide emissions were reduced, while increasing the ratio of ethanol relative to pure gasoline, except PE10 blend. The combustion characteristics were also studied. Lower value of coefficient of variation revealed stable combustion. This study conclude that PE15 can be used as an alternative fuel.

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Now-a-days, journal bearings are subjected to severe loads and higher operating speeds causing generation of high hydrodynamic pressures which in turn deform the bearing shell thus modifying the lubricating film in the operating region. Hence, there is need for optimized bearing performance parameter estimation considering the realistic change in lubricating film along with less computational time. In this paper, response surface optimization module coupled with static structural and fluent, available in ANSYS workbench is used for analysing the performance of the bearing. The optimization is based on Response Surface evaluations. It has been observed that the computation time is considerably reduced. The bearing is analysed for various rotational speeds and eccentricity ratios to obtain load carrying capacity and pressure distribution. It is observed that the results are following the expected trend i.e. as speed increases the load carrying capacity as well as maximum pressure is increasing.