A Survey of Drag and Heat Reduction Induced by Forward-Facing Cavity and Its Combinations

Thermal protection technology is a key technology in the design of hypersonic aircraft. In order to achieve more effective drag reduction and heat protection, scholars have proposed a variety of thermal protection schemes. The forward-facing cavity and its combinations is one of the most effective and promising active thermal protection schemes. This paper introduces the mechanism of single forward-facing cavity and its combination with counterflowing jet, energy deposition and divergent coding, and summarizes their research status. It puts forward the outlook for the future, especially to follow up and innovate the existing combination schemes, and conduct more ground tests to support the numerical simulation results, with a view to early application in the engineering practice.