International Journal of Hydrogen Energy

2019

Numerical investigation on the mechanism of geyser in cryogenic fluid pipes

H.W. Maoa, Y.Z. Liab, L. Wanga, J.j. Wanga, F.S. Xiea
aXi’an Jiaotong University, Institute of Refrigeration and Cryogenic Engineering, Xi’an, 710049, China
bState Key Laboratory of Technologies in Space Cryogenic Propellants, Beijing, 100028, China

摘要：

In order to study the mechanism of geyser in cryogenic fuel system, a CFD model based on VOF method for two-phase heat and mass transfer process is established and validated. The detailed transient behavior and the whole formation process of geyser in a cryogenic pipe are successfully captured and predicted. The prediction performance of 3-D, 2-D axisymmetric and 2-D planar model is evaluated. The formation and development of the whole geyser process are clearly revealed by visualization and macroscopic parameter analysis, and a contrastive study is performed to investigate the mechanism of the pressure peak in a geyser. It is found that: The incubation stage occupies the largest portion of geyser period up to 95% in the presented condition and there is a dramatic pressure fall in the eruption stage and a pressure spike in the refilling stage, which leads to a periodic shock of pressure. The violent depressurization boiling is the main cause of the eruption. Moreover, the water hammer induced by vapor condensation will bring about a huge pressure increase, and it becomes the main mechanism for the pressure spike in the refilling stage.