Operation pattern classification of hypersonic inlets

Operation pattern recognition/classification is one of the most important issues of the hypersonic inlet and is also the foundation of protection control of a scramjet. To solve this problem, the 2-D inner steady flow of the hypersonic inlet was numerically simulated at different freestream conditions and backpressures, and two different inlet unstart phenomena were analyzed. The pattern classifications of hypersonic inlet start/unstart, especial the inlet backpressure unstart/low Mach number unstart were performed based on “numerical experimental” data by the support vector machine algorithms. The physical significance of the classification criterions was explained, and the discussions of the classification criterion used in NASA/CIAM flight test were presented. In conclusion, the operation pattern classification of hypersonic inlet can be solved well by using the support vector machine algorithms.