闪沸喷雾可以在较低的喷射压力下有效提升燃油蒸发和雾化效率，为了研究喷射压力对闪沸喷雾破碎的具体影响及相关机理，基于一款单孔直喷喷油器，利用背光法完成了不同喷射压力和不同过热度下喷雾形态的高速成像试验。对比了喷射压力及过热度对喷雾形态及喷雾破碎的影响，并分析了不同工况下喷雾的破碎机理。研究表明：增加燃油过热度，单孔喷油器喷雾宽度显著增加，喷雾贯穿距明显缩短；对于冷态喷雾，增加燃油喷射压力，喷雾的贯穿距减小，喷雾宽度增加不明显；对于过热喷雾，增加燃油喷射压力，喷雾的宽度显著下降，贯穿距有所增加。

Flash boiling spray can increase fuel evaporation and spray atomization efficiency effectively despite under the low injection pressure. However, in order to study the detailed influences of fuel injection pressure on the breakup process of flash boiling sprays and related mechanisms, the highspeed imaging experiments under different fuel injection pressures and overheat degrees were conducted by using the shadowgraph method on a single-hole fuel injector. Then the impacts of injection pressure and overheat degree on spray morphology and spray breakup were compared and the breakup mechanisms were also analyzed under different conditions. The research shows that the width of spray increases obviously and the penetration shortens remarkably after increasing the overheat degree of fuel. Besides, the spray penetration decreases and the spray width increases unobviously in the cooling spray and slightly increases and obviously reduces in the overheating spray.