Dynamic Measurements of Forward Gas Expulsion during High Speed Stall of Jet Engines

Dynamic measurements taken in a length of pipe mounted in front of a full-scale engine which was intentionally stalled at high corrected speed clearly demonstrate that gases hot enough to stall adjacent engines are expelled forward for a considerable distance. As a consequence, the isolation length of the inlet duct and the provision of adequate stall margin is required to assure compatible inlet flow conditions in clustered engine installations.