Study on Effect of Momentum and Energy Accommodation Coefficient on Flow Properties
Effect of momentum and energy accommodation coefficients on high speed rarefied flow are studied by coupling microscopic (MD) and mesoscopic methods (DSMC). Accurate calculations of momentum and energy accommodation coefficients are very crucial to address the significance of gas-surface interactions in the flow filed. These coefficients are calculated using molecular dynamics simulations and are used as input parameters for studying high speed flows in DSMC. To comprehend the effect of these coefficients, in this work, flow over cylinder (bluff body) at supersonic rarefied flow regime is studied by varying accommodation coefficients. Effect of momentum and energy accommodation coefficients on the primary surface properties viz., drag coefficient and heat flux are studied to establish their significance. Finally, using MD, accurate values of these accommodation coefficients are calculated and are used in DSMC simulations to predict the flow field accurately.