Abstract

Hydrogen is the simplest and the most plentiful element in the universe. It is the cleanest burning fuel with water as the only by-product of the combustion process. Nevertheless, the low energy density per volume of hydrogen requires highly pressurized tanks to store a reasonable amount of energy. Highly pressurized storage tanks increase the risk of tank valve failure and hydrogen release into atmosphere.

In this study, two approaches are developed to investigate sudden hydrogen release. In the first approach, an analytical method is used to analyze the time histories of stagnation properties inside the chamber and sonic properties at the throat. In the second approach, computational fluid dynamics (CFD) analysis is conducted using Ansys CFX solver. Unsteady 3D Navier-Stokes equations along with an additional transport equation are the governing equations of the flow. This CFD analysis is second order accurate in time and space. The SST k-ω turbulence model is employed to study the turbulent properties of the flow. Peng-Robinson real gas EOS is used for the accurate prediction of the hydrogen properties. A fully structured high quality mesh is constructed with