IMAGING OF MIXING AND COMBUSTION PROCESSES IN A SUPERSONIC COMBUSTION RAMJET CHAMBER

Mixing and combustion processes within a supersonic flow in a rectangular duct with a centrally mounted plate injector have been investigated. A supersonic air stream is generated inside this duct using the highspeed flow developed by a vitiated air heater. Hydrogen fuel is injected parallel into this flow, with the resultant mixing and combustion investigated using different optical and laser based diagnostic techniques. Mixing studies have been performed in a non-reacting supersonic flow to investigate both the compressibility effect of a supersonic mixing layer and a shock induced mixing layer enhancement technique. The results show a pronounced decrease of the normalized growth rate of the compressible mixing layer, whereas shock impingement onto the mixing layer results in a slight growth rate enhancement. Planar laser-induced fluorescence of OH has been applied in order to characterize the combustion process within the supersonic flow field.