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The supercritical turbulent flow of cryogenic methane flowing in a rocket engine cooing channel is numerically analysed by imposing constant heat flux at the bottom surface of the channel. The calculation scheme is validated by comparing the results obtained with experimental results reported in literature. The heat transfer coefficient is influenced by the strong variation in thermophysical properties of methane at super critical pressure. An increasing trend in the average value of Nusselt number is observed with aspect ratio. The efficacy of both Modified Jackson and Hall and Bishop empirical correlations in predicting Nusselt number is tested for cryogenic methane flowing in coolant channels.

Abstract.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.

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Abstract. All the re-entry vehicles usually travel at hypersonic velocities, there are some design constraints pertaining to them such as aerodynamic drag and heat, which are mutually conflicting. A sharp edged slender body offers longer range and lesser drag but it causes higher aerodynamic heat. Generally, blunt shaped nose is used for the re-entry vehicles as it can disperse the accumulated heat to the surroundings better than sharp edged bodies. The current work focuses on reduction of aerodynamic heating by the introduction of a single jet injection on the stagnation point. Different jet angle configurations are used for the analysis by maintaining the angle of attack of the body constant. It is found that for body at 6-degree angle of attack the optimum jet angle is 9 degrees and the corresponding reduction in peak heat flux is 22.7% compared to the heat flux when the jet is at zero degrees and 33% compared to the case without jet.