REGENERATIVE/FILM/TRANSPIRATION COOLED STRUCTURAL PANEL

A hypersonic engine application may require a sophisticated system to maintain the hot wall structure of the combustion chamber within structural temperature limits. Ablative insulation protects the structure for single mission requirements, but regenerative cooling is required for reusability or severe flight envelopes. At the upper limits of the hypersonic engine operating envelope, transpiration film cooling may be required, possibly in indeterminate localized regions due to combustion variations or operating requirements. A hybrid hot wall cooling panel is proposed which incorporates a regenerative cooling design that will automatically add localized film cooling when the hot wall reaches a critical temperature where regenerative cooling is insufficient to maintain structural integrity. Film cooling is injected along the surface at local hot spots or throughout the panel for general high temperature operation to augment the regenerative cooling. The film coolant is injected at multiple discrete locations along the boundary layer to minimize local flow disturbances and to prolong the effectiveness of the film isolation if the hot combustion cages from the cooled wall for the longest distance; thus minimizing the amount of added coolant flow required to maintain acceptable operating wall temperatures.