摘要
螺旋进气道在铸造和机械加工过程中会出现各种各样的偏差,从而影响直喷式柴油机的动力经济性和排放特性.作者设计了几种机构来模拟不同类型的偏差,如带有倾斜误差的进气道、带有纵向胀大误差的进气道以及带有偏心误差的进气道等.在稳流试验台上检测气道的流动特性.实验结果表明,倾斜气道会显著影响涡流比.抬高气道入口端会明显降低涡流比,反之则涡流比提高;气道胀大会使流量系数和涡流比都降低;当偏心出现在气道出口方向时,涡流比略有增加;当偏心出现在气道入口方向时,涡流比会显著降低.
The flow performance of the helical intake port has great influences on direct injection(DI) diesel engine combustion and performances. Many errors or deviations may occur during the casting and machining processes of the cylinder head. In this paper, a few sets of mechanism were designed for simulating different kinds of port deviation, e.g. port with inclination, vertical swelling and eccentric errors etc. The flow performance of the port was tested on a steady state flow rig. The results are as follows. The inclination of the inlet port influences greatly the swirl ratio of the port. Raising the entrance end of the port will lead to the reduction of the port swirl ratio, while reducing the entrance end of the port will lead to a higher port swirl ratio. The swelling of the inlet port will cause either flow coefficient or swirl ratio of the port to be reduced. As the eccentric deviation occurs at the direction of the exit of the port the swirl ratio will be increased a little, while the eccentric deviation occurs at the direction of the entrance of the port the swirl ratio will be reduced considerably.
出处
《燃烧科学与技术》
EI
CAS
CSCD
2003年第5期397-403,共7页
Journal of Combustion Science and Technology
关键词
直喷式柴油机
螺旋进气道
形状位置偏差
流量系数
涡流比
direct injection diesel engines
helical inlet port
shape and position deviations
flow coefficient
swirl ratio
