Response of angled and tapered liquid injectors to passing detonation fronts at high operating pressures

High-diodicity impinging injector design for rocket propulsion enabled by additive manufacturing

“…A similar manifold pressure variation is measured by researchers at Purdue in Ref. [2]. As seen in Fig.…”

“…The fluidic diode developed in this work will combine the hydraulic benefits of "tapering" the injector element, demonstrated to be efficient in Ref. [2,7], and the redirection of flow in the reverse direction similar to a Tesla valve.…”

“…As seen in Fig. 5, a time-varying outlet boundary condition is set at 𝑡 = 10 µs to mimic the pressure profile of an impulsive, high-pressure wave traversing an injector orifice and assumes the shape of an exponential decay function [2,10,11]. A time-step size of 1×10 −7 seconds was found to be sufficient for a converged solution with 20 iterations per time-step.…”

“…An approach which allows for the simultaneous fulfillment of these requirements is the implementation of an injector geometry to resist reverse flow without hindering forward flow. Some recent efforts have explored geometric modifications to impinging injector schemes to enhance backflow resistance and recovery characteristics by angling injector elements relative to the direction of a transverse pressure/shock wave [2]. This angling resulted in only minimal performance improvements due to difficulty in predicting the direction of the wave propagation and a rise in potentially harmful cavitation near the injection plane.…”

“…This angling resulted in only minimal performance improvements due to difficulty in predicting the direction of the wave propagation and a rise in potentially harmful cavitation near the injection plane. The tapering of injector orifices led to noticeably faster propellant recovery times, which is speculated to be the result of the product gases having a larger volume to fill and expand, thus decreasing its pressure [2]. In this work, we examine the potential of additive manufacturing to enable impinging injection designs that provide enhanced backflow resistance or diodicity.…”