Visualisation of Jet Fires From Hydrogen Release

In order to achieve a high level of safety while using hydrogen as a vehicle fuel, the possible hazards must be estimated. Especially hydrogen release tests with defined ignition represent a very important way to characterize the basics of hydrogen combustion in a potential accident. So ICT participated on a hydrogen jet release campaign at HSL (Buxton) in 2008, to deploy their measurement techniques and evaluation methods to visualize jets, ignition and subsequent flames. The following paper shows the application of high speed cinematography in combination with image processing techniques, the Background Oriented Schlieren (BOS) and a difference method to visualize the shape of hydrogen jet. In addition, these methods were also used to observe ignition and combustion zone after defined initiation. In addition the combustion zone was recorded by a fast spectral radiometer and a high-speed-IR-camera. The IR-camera was synchronized with a rotating filter wheel to generate four different motion pictures at 100Hz each on a defined spectral range. The results of this preliminary evaluation provide some detailed information that might be used for improving model predictions.