No abstract

No abstract

Liquid rocket engines (LREs) are essential power sources for access to space. Electric pump feed systems have received noteworthy attention because of their high efficiency, convenient regulation, and simple structure. In this study, an oxidant feed system with two pumps in parallel was established. The centralized parameter method and the distributed parameter method were used for modeling. The dynamic characteristics of different starting schemes and regulating schemes were obtained. The results show that the asynchronous opening of two pumps led to a pressure peak from the second stage to the third stage. Under the low operating conditions, the pump speed of the asynchronous scheme was about 13,300 r/min, the pump speed of the synchronous scheme was about 12,100 r/min, and the pump speed of the joint adjustment scheme was about 24,800 r/min. The joint adjustment of pump speed and valve opening could increase the pump speed by a factor of one-third, while maintaining the efficiency at a high level. The optimal scheme could be selected according to a genetic algorithm-based calculation process, together with the curves of the flow rate and pressure with pump speed and valve opening. This study can contribute to the application of electric pumps for liquid rocket propulsion.

No abstract

Liquid rocket engines with hydrogen peroxide and kerosene have the advantages of high density specific impulse, high reliability, and no ignition system. At present, the cooling problem of hydrogen peroxide engines, especially with regenerative cooling, has been little explored. In this study, a realizable k-epsilon turbulence model, discrete phase model, eddy dissipation concept model, and 10-step 10-component reaction mechanism of kerosene with oxygen are used. The increased rib height of the regenerative cooling channel causes the inner wall temperature of the engine increases, the average temperature of the coolant outlet decreases slightly, and the coolant pressure decreases. The overall wall temperature decreases as the rib width of the regenerative cooling channel increases. However, in the nozzle throat area, the wall temperature increases, the average coolant outlet temperature decreases, and the coolant pressure drop increases. A decrease in the inner wall thickness of the regenerative cooling channel results in a significant decrease in the wall temperature and a small increase in the average coolant outlet temperature. These findings contribute to the further development of the engine with hydrogen peroxide and can guide the design of its regenerative cooling process.