%A REN Xiaowen, LI Ping, CHEN Hongyu, ZHOU Chenchu
%T Simulation of two-phase filling characteristics of storable propellant in pipelines
%0 Journal Article
%D 2022
%J ACTA AERONAUTICAET ASTRONAUTICA SINICA
%R 10.7527/S1000-6893.2021.25047
%P 125047-125047
%V 43
%N 2
%U {https://hkxb.buaa.edu.cn/CN/abstract/article_18993.shtml}
%8
%X The two-phase filling characteristics of the storable propellant in the pipeline are difficult to predict due to the interaction of gas and liquid. To expand the simulation capabilities of the modular general simulation library for liquid rocket engine transient characteristics for two-phase filling, a two-phase filling pipeline model with one-dimensional finite volume is developed based on the Modelica modular modeling idea. In this model, the equivalent fluid capacity equation and the Volume of Fluid (VOF) method are adopted to calculate the pressure and capture the gas-liquid interface, respectively. The comparison of the discrete formats of advection terms shows that the TVD_QUICK scheme can guarantee the accuracy and real-time performance simultaneously for system simulation. The research on the orifice diameter shows that the filling process of the liquid to the pre-existing gas pipeline can be divided into three modes within the range of different throttle aperture ratios, namely, negligible water hammer effect, weak water hammer effect and dominant water hammer effect, and the peak pressure of water hammer generally occurs in the mode of dominant water hammer effect. In addition, the pressure shock shown by the storable propellant with a single gas column in the filling process is mainly caused by two factors. One is the pressure fluctuation of gas column compressed by the upstream and downstream liquid columns, and the other is the water hammer pressure shock generated by the liquid column downstream of the air column at the position of the throttle element. With the coupling of the two pressure fluctuations, the peak water hammer pressure in the pipeline reaches about 5 times the upstream supply pressure.