Experimental study on the atomization characteristics of afterburner under multimodal two-stream effect

<bold> </bold>The gas flow rate in the afterburner of the variable cycle engine will change synchronously with the conversion of the working mode, and the corresponding wide range of the ducted gas blending flow will have a significant impact on the atomization characteristics of the afterburner. In order to explore the atomization characteristics of the multi-duct afterburner under different working modes, the atomization characteristics of the downstream area of the nozzle of the multi-duct afterburner were measured by laser scattering method and shadow imaging method, and the macroscopic characteristics and microscopic characteristics of the atomization field of the afterburner under different incoming flow conditions were obtained. The results show that when the core flow temperature is 700 K, and the Mach number of the core flow remains unchanged, the width of the atomization field region increases by 3.20% due to the increase of the bypass ratio, and increased intensity of the bypass flow improves the structural stability of the atomization region. When the core flow temperature increases from 300 K to 700 K, the number of droplets with a diameter of less than 50 μm decreases by 40.07% on average. The proportion of droplets with a diameter greater than 100 μm is expected to increase by an average of 77.39%, while the Sauter mean diameter of droplets in the atomization field increases.