CFD Analysis on Mixing Characteristics of Supersonic Combustor with Tandem Cavity

Abstract

The design of scramjet engines hinges significantly on the cavity configuration. Among the various options, the tandem dual cavity emerges as a promising choice for augmenting engine performance. This investigation employs the tandem dual cavity in a supersonic combustor, maintaining a constant set of parameters while varying Mach numbers. The primary objective is to identify optimal conditions that maximize the thorough mixing of air–fuel and ensure flame stability within the engine operating at supersonic speeds. This computational study delves into the behavior of the flame, utilizing hydrogen gas as fuel and atmospheric air as the direct oxidizer in the combustor featuring a tandem dual cavity. The upstream cavity proves instrumental in flame stabilization, revealing an intense combustion region near the downstream cavity. Comparison across three distinct Mach numbers, while keeping other variables constant, highlights that a Mach number of 4.0 yields the most favorable outcomes within the specified range. The findings underscore the formation of two vortex types due to the cavity, with the larger one facilitating a stable flame and the smaller one safeguarding the cavity wall from heat. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.