A novel strategy to enhance the cooling effectiveness in a confined porous jet impingement using non-Newtonian fluids

摘要

Jet impingement configuration is commonly employed in the thermal management of the gas turbine engines, rocket launchers, and high-density electrical equipment cooling to remove a large amount of heat. Owing to such overwhelming applications, significant research efforts have been devoted to enhance the cooling performance of jet impingement configuration. In this work, the influence of shear-thinning behaviour in overall heat transfer characteristics have been investigated as a function of pertinent dimensionless numbers as 10~(-6) ≤ Da ≤ 10~(-2) (Darcy number), 1 ≤ Pe ≤ 10~2 (Peclet number), 0 ≤ Ri ≤ 4 (Richardson number), 0.4 ≤ n ≤ 1 (shear-thinning index). The numerical results on local thermal non-equilibrium (LTNE) parameter, streamlines and isotherms, local and average Nusselt number are reported for a range of power-law index, pA©clet number and Richardson number. All in all, shear-thinning fluids offer 50-60% enhancement in Nusselt number with reference to the Newtonian fluid at a higher Darcy number. A correlation for average Nusselt number is put forward to enable its use for process design calculations.