Effect of aspect ratio on heat transfer and fluid flow in regenerative cooling channel of liquid rocket engine thrust chamber

The turbulent fluid flow and heat transfer in a regenerative-cooling channel of liquid propellant rocket engine were numerically investigated by solving three-dimensional elliptical Navier-Stokes equations. The coolant was hydrogen, whose thermal properties such as thermal conductivity, density, dynamical viscidity, etc varied with both temperature and pressure. The specific heat of hydrogen and thermal properties of solid metal varied with temperature. The standard k-ε turbulence model and gas-solid coupled technique were adopted. An optimized calculation scheme was applied so as to find the best design for rocket combustion chamber. In the scheme, the cooling channel aspect ratio varied with the thickness of channel ribs while the channel number is fixed and coolant mass flow rate remains constant. The simulation results show that the heat transfer of rocket chamber will be enhanced when increasing the aspect ratio, but the pressure drop will increase simultaneously. The cooling effect of rocket thrust chamber will to be reach saturated as the aspect ratio becomes large enough.