A numerical study of Tesla valve integration into rotating detonation engines

Rotating Detonation Engines (RDEs) represent a promising propulsion technology characterized by continuous detonation waves traveling supersonically within an annular combustion chamber. RDEs achieve higher thermodynamic efficiency compared to conventional deflagration-based systems. However, critical challenges in RDE operation involve sustenance of stable detonation with consistent fuel-air mixing and avoidance of reverse flow. A series of Tesla valves, known for their unidirectional flow, are designed within the inlet of an RDE to passively avoid reverse flows. The performance of the novel RDE is compared with that of a baseline design with numerical computations of deflagration to detonation transition in identically premixed hydrogen air mixtures admitted through a plenum. The computational domains include the plenum, the injectors without and with the Tesla valves, and an annular combustion chamber. A two-dimensional unwrapped RDE configuration is considered. The transient Navier-Stokes equations are solved with a multistep hydrogen-air mechanism. The key computational results are that the Tesla valve�s unique geometry effectively minimizes the backpressure in the plenum, stabilizing the inflow conditions essential for maintaining continuous detonation. The smooth continuous forward flow improves the mixing efficiency of reactants and products upstream of the detonation wave. The smooth continuous forward flow lowers the pressure fluctuations at the inlet by isolating it from the shock waves generated within the detonation chamber. Future work is planned for optimizing the system geometry with a special focus on optimizing the Tesla valve geometries and evaluating the performance under varying operational conditions first numerically and followed by experiments.