Experimental investigation on heat transfer deterioration and thermo-acoustic instability of supercritical-pressure aviation kerosene within a vertical upward circular tube

Abstract

The flow and heat transfer of China RP-3 (Rocket Propellant 3) aviation kerosene has been experimentally studied at supercritical pressures in a vertical upward circular tube, primarily focusing on the formation mechanisms and critical conditions for deteriorated heat transfer and thermo-acoustic instability in the regenerative cooling process. The effects of key parameters, including the heat flux, inlet fluid temperature, pressure and mass flow rate, on these two processes were investigated, and new empirical criteria regarding the critical condition for deteriorated heat transfer and thermo-acoustic instability prediction were established. Furthermore, a heat transfer correlation under stable flow conditions was developed. The results indicate that, for the supercritical convective heat transfer process, both heat transfer deterioration and thermo-acoustic instability occur when the temperature of the near-wall fluid reaches its pseudo-critical point, the former is caused by a high buoyancy and thermal acceleration, while the latter results from the pseudo-boiling effect. Increasing the inlet fluid temperature, pressure, and mass flow rate can effectively weaken these two phenomena. The critical condition and heat transfer prediction expressions can be applied to supercritical-pressure aviation kerosene-type endothermic hydrocarbon fuel.