Simulation and performance analysis of the perforated plate flowmeter for liquid hydrogen

The flow rate measurement of the liquid hydrogen (LH2) is of significance for the effective and safe operation of the systems dealing with massive liquid hydrogen, e.g., hydrogen stations and hydrogen fuelled space rockets. A perforated plate flowmeter is one of the effective devices for measuring flow rate accurately. In order to explore the optimal structure of a perforated plate flowmeter, the perforated plates with different perforating form, thickness, equivalent diameter ratio and hole diameter are numerically investigated with the help of ANSYS Fluent, mainly focusing on discharge coefficient C and pressure loss coefficient ζ, when applied to liquid hydrogen. The realizable k-ε model is adopted to describe the turbulence. Schnerr-Sauer cavitation model is employed for the case of cavitation to investigate the cavitation effect on the performance of the perforated plate. The simulation results reveal that the perforated plate with a larger center hole diameter is more suitable for measuring liquid hydrogen than that with the equal-aperture holes, especially for the case of the perforating form matching the turbulent velocity distribution in the circular tube. The equivalent diameter ratio is the dominant factor influencing the liquid hydrogen cavitation, and the reasonable increases of plate thickness and equivalent diameter ratio help to improve the performance of perforated plates applied to liquid hydrogen.