Experimental and Numerical Investigations on the Mixing Process of Supercritical Jet Injected into a Supersonic Crossflow

Abstract

The mixing process and distribution characteristics of a supercritical endothermic hydrocarbon fuel (EHF) jet injected into a supersonic crossflow were investigated by experimental and numerical methods, respectively. The schlieren system and acetone planar laser-induced fluorescence (PLIF) optical system were used to capture the flow-field structural characteristics and instantaneous plume. The mixture and real gas models were employed to calculate the interaction of a transverse jet and supersonic crossflow and reveal a good accuracy with the experimental results. The mixing efficiency and total pressure loss were analyzed based on the numerical results. The results indicate that the supercritical-state EHF directly changes to a gaseous state as it enters the supersonic crossflow from the injector. The EHF jet plume boundary increases with the increasing momentum flux ratio (q). As the streamwise and spanwise distance increases, the traverse heights and expand width increase, and the EHF jet plume presents a semicircle shape in the cross-sectional plane. With the increase in the traverse direction, the concentration distribution shows a fast and then slow power exponential decreasing law; the highest concentration point starts from the near-wall region and rises in the transverse direction with the flow distance increasing. For the same injection condition, the higher the inflow Mach number, the higher the mixing efficiency. For the same Ma, the mixing efficiency is better for the case with low injection pressure and high injection temperature. The total pressure loss is greater in the higher Ma, and high injection pressure conditions cause greater total pressure loss.

Experimental Investigation of a Micro Turbojet Engine Chevrons Nozzle by Means of the Schlieren Technique

“…To model the interaction between a transverse jet and a supersonic crossflow, mixture and real gas models were utilized, demonstrating a high level of accuracy compared to experimental results. The numerical results were also used to analyze mixing efficiency and total pressure loss [26]. Furthermore, low-cost methods for visualizing and analyzing pulsed synthetic jets in cooling applications were employed in another study [27].…”

Cмешение Струй Газов Различной Молекулярной Массы С Высокоскоростным Потоком Воздуха При Изменении Их Динамического Напора

“…К настоящему времени имеется значительное количество как численных, так и экспериментальных работ, в которых рассматриваются различные схемы инжекции [2]. Одной из самых распространенных и надежных схем, обеспечивающих быстрое перемешивание газа с воздухом и глубокое проникновение струй в высокоскоростной поток, является поперечная по отношению к потоку инжекция через сопла, вмонтированные в стенки канала [3][4][5]. Проникновение струй зависит от многих параметров: формы выходного отверстия и количества инжекторов, химического состава и молекулярной массы инжектируемого газа и т. д.…”