Computational method about the pre-cool filling process in the feed pipe of cryogenic liquid propellant was studied.By using one-dimension homogeneous balance fluid dynamic model and a heat transfer model covering main heat transfer work condition in pre-cooling process

and also taking into account of the compressibility of cryogenic liquid propellant

a finite volume method was used to calculate the pipe flow formula

and a finite difference method used to calculate one-dimension non-steady heat conduction formula of inner pipe-wall.The pre-cool filling process in the feed pipe of cryogenic liquid propellant for a test-bed system of cryogenic liquid rocket engine was computed

while the simulative and experimental results were also analyzed

thus providing a basis for improvement of rocket engine and test-bed system and design of a new system.The simulative results and analytical conclusion have been applied to revamping of existing engine experimental system and design of long-distance liquid hydrogen pipeline.