An experimental investigation into small pressure-swirl spill-return atomizers was made to determine the effect of the entry port number, swirl-chamber shape, spill-line design, and the manufacturing precision on the spray quality and stability. The atomizers were studied using phase-Doppler anemometry, high-speed visualization, and mechanical patternation. Jet A-1 fuel was sprayed at inlet pressures of 0.5, 1.0, and 1.5 MPa and for spill-to-feed ratios of 0, 0.4, and 0.8. The chamber shape influenced the spray characteristics of the simplex atomizers only moderately with no systematic effect of conical chambers to the others. The spray was found to be circumferentially heterogeneous; its uniformity improved with increase in the pressure, while the effect of swirling port number was negligible. Atomizers with axial spill orifice demonstrated strong spray pulsations at a spill-to-feed ratio of zero. A periodic decay of the air core was identified as a possible reason for the pulsations. Atomizers with off-axis spill orifices always produced a stable spray. Atomizers with tangential inlet ports provided a finer spray than those with helical ports. Manufacturing precision, axial symmetry, and matching of the surfaces of connected parts were found important for the spray symmetry and homogeneity.

对小型压力旋流式溢流返回雾化器进行了实验研究，以确定入口数量，旋流室形状，溢流管线设计以及制造精度对喷雾质量和稳定性的影响。使用相位多普勒风速仪，高速可视化和机械图案研究了雾化器。在入口压力分别为0.5、1.0和1.5 MPa的情况下以喷射喷射A-1的燃料进行喷射，进料比为0、0.4和0.8。腔室的形状仅适度地影响了单纯雾化器的喷雾特性，而锥形腔室对其他雾化器没有系统性的影响。发现该喷雾在圆周上是异质的。其均匀性随压力的增加而提高，而回旋口数的影响可忽略不计。带有轴向溢流孔的雾化器在零进料比为零的情况下显示出强烈的喷射脉动。空芯的周期性衰减被确定为产生脉动的可能原因。带有离轴溢流孔的雾化器始终产生稳定的喷雾。具有切向入口的雾化器比具有螺旋形入口的雾化器提供更细的喷雾。发现制造精度，轴向对称性以及连接零件的表面匹配对于喷雾对称性和均匀性很重要。