Experimental study on the wall temperature and heat transfer of a two-phase pulse detonation rocket engine

An experimental work was conducted to study the wall temperature and heat transfer on a two-phase pulse detonation rocket engine. Three pressure transducers were employed to validate the fully developed detonation wave in the tube, while six thermocouples were used to measure the increasing temperature of the tube wall and calculate the heat load. The heat flux on the deflagration-to-detonation transition (DDT) section could be in the order of megawatt per square meter, which was 1.27-2.81 times that of the propagation section. The effects of operating conditions, such as the operating frequency and the equivalence ratio, on the heat load were also investigated. A positive correlation was observed between the heat load on the tube wall and the operating frequency, but the increasing trend would slow down gradually with the operating frequency. In addition, as the equivalence ratio increased, the heat load increased initially and decreased afterwards. It is suggested that the fuel-rich conditions should be avoided considering fuel wasting and tube wall over-heating. Moreover, heat transfer enhancement and heat-insulating coating should also be used to sufficiently cool down the engine, especially the DDT section.