Analysis of Fluid Flow and Heat Transfer in a Liquid Hydrogen Storage Vessel for Space Applications

Abstract

This paper presents a systematic analysis of fluid flow and heat transfer in a liquid hydrogen storage vessel for both earth and space applications. The study considered a cylindrical tank with elliptical top and bottom. The tank wall is made of aluminum and a multi-layered blanket of cryogenic insulation (MLI) has been attached on the top of the aluminum. The tank is connected to a cryocooler to dissipate the heat leak through the insulation and tank wall into the fluid within the tank. The cryocooler has not been modeled; only the flow in and out of the tank to the cryocooler system has been included. The primary emphasis of this research has been the fluid circulation within the tank for different fluid distribution scenario and for different level of gravity to simulate potential earth and space based applications. The equations solved in the liquid region included the conservation of mass, conservation of energy, and conservation of momentum. For the solid region only the heat conduction equation was solved. The steady-state velocity, temperature, and pressure distributions were calculated for different inlet positions, inlet velocities, and for different gravity values. The above simulations were carried out for constant heat flux and constant wall temperature cases. It was observed that a good flow circulation could be obtained when the cold entering fluid was made to flow in radial direction and the inlet opening was placed close to the tank wall.

Forced convective mixing in a zero boil-off cryogenic storage tank

“…The model predicted that a ZBO densified liquid hydrogen storage system minimizes the overall storage system mass and volume for nearly the same input power for cooling. Mukka and Rahman [12,13] used computational fluid dynamics (CFD) simulation to study the fluid flow and heat transfer in a cryogenic liquid hydrogen storage tank of displacement type where cool fluid enters the tank at one end, mixes with hot fluid, and exits the other end. Mahmoud et al [14] presented a model that predicts the amount of liquid parahydrogen vaporized during a discharging/charging process for a cryogenic storage system.…”