Real-size Calculation of High-pressure Hydrogen Flow and its Auto-ignition in Cylindrical Tube

A real-size calculation is performed for high-pressure hydrogen release in a tube using the axisymmetric Navier–Stokes equations with the full hydrogen chemistry. A Harten–Yee-type total variation diminishing scheme and point-implicit method are used to integrate the governing equations. The calculated real-size results show that the leading shock wave velocity is similar to that calculated using a smaller tube. The mixing process and ignition behaviour of high-pressure hydrogen are explained in detail; the velocity shear layer and Kelvin–Helmholtz instability are the main causes of mixing of hydrogen with air and ignition in the high-temperature region behind the leading shock wave.