Implementation of large scale shadowgraphy in hydrogen explosion phenomena

• We document the construction of a large-scale shadowgraphy system.
• The system is used to visualize jet releases, unconfined flames, and detonations.
• Analysis of high-speed reactive gas dynamics is shown on the 1 m scale.
• High-quality shadowgraphs obtained are qualitatively similar to schlieren images.

The purpose of this study is to determine the performance of a portable large-scale shadowgraph system for use in hydrogen combustion experiments. Previous large-scale shadowgraph and schlieren implementations have often been limited to background-oriented techniques which are subject to noise. The system built is based on a large-scale shadowgraph technique, developed by Settles, which allows for noise-free visualization. We performed jet release, unconfined flame and detonation experiments in hydrogen mixtures. Shadowgrams taken were compared to a Z-schlieren system. Large-scale shadowgraphy offered high-quality visualization of hydrogen explosion phenomenon.