关键词: 常温推进剂, 充填, 管路, 气液两相, 水击

Abstract: The two-phase filling characteristics of the storable propellant in the pipeline are difficult to predict due to the interaction of gas and liquid. In order to expand the simulation capabilities of the modular general simulation library for liquid rocket engine transient char-acteristics for two-phase filling, a one-dimensional finite volume two-phase filling pipeline model is developed based on the Modeli-ca modular modeling idea, in which the equivalent fluid capacity method is used to calculate the pressure, and the VOF method is adopted to capture the gas-liquid interface. 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 di-ameter 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 ratio, namely, negligible water hammer effect, mitigate 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 pres-sure 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 column, 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 pipe reaches about 5 times the upstream supply pressure.

Key words: storable propellant, pipeline, filling, gas-liquid two-phase, water hammer