Dynamic characteristics and sensitivity of water hammer problems in liquid propulsion system using lattice Boltzmann method with entropy limiter

The water hammer problem is an important issue in the dynamics of liquid propulsion system. This paper aims to use the Lattice Boltzmann Method (LBM) with entropy limiter to study the water hammer problems in propellant feedlines. The dynamic characteristics of valve-closing water hammer and filling water hammer are investigated by this method, and the sensitivity of filling water hammer is analyzed with a single factor sensitivity analysis with 8 factors and 9 levels and a multi-factor sensitivity analysis with L₂₇(3¹³) orthogonal experiment based on range method. It is found that the solving result of LBM with entropy limiter is basically in good agreement with finite volume method, and using the entropy limiter can eliminate numerical oscillations when solving valve-closing water hammer problems and solve the numerical “blow up” when solving filling water hammer problems. It can be seen that the dynamic characteristics of valve-closing water hammer are relatively simple, while there are many factors that affect the filling water hammer and the degree of these effects varies. The effects on the maximum water hammer pressure are relatively uniform, but those on the water hammer response time vary greatly through the skewness analysis.