Progress on numerical simulation of thermal protection/friction reduction using supersonic fuel film with boundary layer combustion: a review

Organizing supersonic fuel films near the wall offers a promising solution to simultaneously reduce friction and thermal loads in the internal flow passages of hypersonic vehicles. This paper presents a thorough review of the supersonic fuel film cooling from a numerical perspective. First, the foundational concepts and features of supersonic fuel films are outlined. Second, several critical issues in successfully modeling their flow and combustion processes are discussed in detail. Progress in numerical studies pertinent to supersonic fuel films is then summarized, mainly focusing on slot films, hole films, and shock-film-combustion interactions. Existing studies have demonstrated the feasibility of improving thermal protection and friction reduction performance of supersonic fuel films by boundary layer combustion, and provided preliminary insights into the underlying mechanisms. Nonetheless, current research status remains insufficient to achieve a comprehensive understanding of the effects induced by boundary layer combustion on fuel films. Key knowledge gaps and future research priorities are highlighted in the conclusion.