Cavitation-induced ignition of cryogenic hydrogen-oxygen fluids

TL;DR

This paper proposes a cavitation-induced ignition mechanism for cryogenic hydrogen-oxygen fluids, explaining how shock waves from bubble collapse can trigger self-ignition and detonation, relevant to rocket safety and failure analysis.

Contribution

It introduces a novel cavitation-based ignition model for cryogenic H2/Ox fluids, linking bubble collapse to self-ignition phenomena in cryogenic conditions.

Findings

Shock waves from vapor bubble collapse can initiate ignition.

H2/Ox combustion inside collapsing bubbles enhances ignition.

Mechanism explains self-ignition in cryogenic H2/Ox systems.

Abstract

The Challenger disaster and purposeful experiments with liquid hydrogen (H2) and oxygen (Ox) tanks demonstrated that cryogenic H2/Ox fluids always self-ignite in the process of their mixing. Here we propose a cavitation-induced self-ignition mechanism that may be realized under these conditions. In one possible scenario, self-ignition is caused by the strong shock waves generated by the collapse of pure Ox vapor bubble near the surface of the Ox liquid that may initiate detonation of the gaseous H2/Ox mixture adjacent to the gas-liquid interface. This effect is further enhanced by H2/Ox combustion inside the collapsing bubble in the presence of admixed H2 gas.