摘要
本文在定容弹中用高速摄影研究了环境气体温度和密度对喷射压力为75～134MPa的柴油机喷雾贯穿距离、喷雾角及碰壁过程的影响.结果表明,环境温度对高压喷雾的影响远比对常规压力喷雾显著.环境温度升高后,高压喷雾的贯穿距离有所减小,而喷雾角则明显增大,在高温高密度下,喷雾角可增至30°以上.高压喷雾与常温壁面碰撞时,几乎看不到反跳现象,但在壁温较高时,壁面附近将有较浓密的液雾,且在液雾和壁面间有一蒸气层.环境密度对高压喷雾的影响在定性上与对常规压力喷雾相同.当喷射压力由75MPa提高到134MPa时,贯穿距离反而有所减小.本文根据这一实验结果提出了一个考虑了喷射压力和温度影响的计算贯穿距离的经验公式.
The effect of gas temperature and density on the penetration, spray angle and wall impingement of diesel fuel sprays at an injection pressure of 75-134 MPa was studied in a constant volume bomb by means of the high speed photography, The resuls show that the effect of ambient temperature on the sprays at high injection pressure is much stronger than that at normal injection pressure. In the former case. when the temperature rises, the spray tip penetration will decrease while the spray angle will increase remarkably; after impinging on the wall, the reflected spray can be recorded by photo- graphy only if the wall is hot, it is different from the latter case. when the injection pressure rises from 75 MPa to 134 MPa, the penetration will decrease. Considering this fact, an empirical formula has been presented.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
1992年第3期255-261,共7页
Transactions of Csice
关键词
柴油机
喷雾
碰壁过程
环境
气温
Diesel fuel spray
High injection pressure
penetration
Spray angle
Wall impingement
