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Of late Direct Injection Spark Ignition (DISI) engines are replacing the carburetted SI engines due to certain inherent advantages like uniform distribution of fuel-air mixture in all cylinders in multi cylinder engines. However the homogeneity of the mixture depends on the time of injection as well as the type of fuel injector. It is expected that late in the compression stroke the fuel-air mixture near the spark plug should be a combustible mixture. In order to achieve this, proper air motion during induction and compression is a must. Further the interaction of fuel and air from the start of injection is equally important. This paper addresses these issues. For this a CFD study has been carried out. The injection timings selected are 90, 180 and 2700 aTDC, the idea being to understand the effects of early or late injection on fuel air mixing. The appropriate governing equations are solved using finite volume method. RNG k-ε turbulence model is used for physical modelling.

A gas turbine combustion system is an embodiment of all complexities that engineering equipment can have. The flow is three dimensional, swirling, turbulent, two phase and reacting. The design and development of combustors, until recent past, was an art than science. If one takes the route of development through experiments, it is quite time consuming and costly. Compared to the other two components viz., compressor and turbine, the combustion system is not yet completely amenable to mathematical analysis. A gas turbine combustor is both geometrically and fluid dynamically quite complex. The major challenge a combustion engineer faces is the space constraint. As the combustion chamber is sandwiched between compressor and turbine there is a limitation on the available space. The critical design aspect is in facing the aerodynamic challenges with minimum pressure drop. Accurate mathematical analysis of such a system is next to impossible.

In the present work, an attempt was made to study numerically, using CFD, the effect of vane-shape on the flow-field and heat transfer characteristics of a disc brake rotor for different configurations and at different speeds. Initially, the CFD code used in this work was validated by experimental results obtained by conducting experiments on a test rotor using particle image velocimetry (PIV). Further, six types of rotor configurations viz., straight radial vane (SRV), tapered radial vane (TRV), modified tapered radial vane (MTRV), circular pillared (CP), diamond pillared (DP) and modified diamond pillared (MDP) were considered for the numerical analysis. Three of them were radial type and other three were of pillared type rotors. A rotor segment of 20° was considered for the numerical analysis due to rotational symmetry. Validation was done for SRV rotor, for which the experimental and predicted results were in good agreement.

Increasing the efficiency of engine auxiliary systems have become a challenge. Oil pump, identified for this study, is one such engine system which is used for lubrication of engine parts. To achieve higher efficiencies, there is a need for math-based analysis and design. This can be achieved by means of Computational Fluid Dynamics (CFD). The main aim of this paper is to simulate the flow through Gerotor Oil pump using Computational Fluid Dynamics. A 3D model of the entire flow domain is created and meshed in preprocessor GAMBIT. The mesh for various pressure outlet conditions is exported to FLUENT solver for analysis. The predicted results are validated with the experimental results. The comparison shows that the CFD predictions are in good agreement with experimental results. In particular, such a simulation offers a scope for visualizing the flow through the Gerotor oil pump.

The objective of present study is to predict and analyze the flow through the Carburettor for two different throttle opening conditions. The studies have been carried out by Computational Fluid Dynamics (CFD) software and the prediction has been validated with experimental data. Three dimensional geometrical models of two different throttle positions namely 50% opening and wide open throttle (100% throttle opening) were created using the commercially available software. The mesh was generated using the Tet-hybrid scheme which includes primarily of tetrahedral mesh elements but may also include hexahedral, pyramidal and wedge elements. The pressure boundary conditions are used to define the fluid pressure at the inlet and outlet of the carburettor. The steady state flow field analysis inside a carburettor has been simulated using the Multiphase mixture model and Langrangian Discrete phase model.