| 王达，晁岳栋，邓俊，杨陈，沈源，李理光.高压缩比活塞顶形状对湍流动能和缸内气流的影响[J].内燃机工程,2019,40(3):56-64. |
| Effects of High Compression Raito Piston Geometry on Turbulence Kinetic Energy and Air Flow in Cylinder |
| DOI：10.13949/j.cnki.nrjgc.2019.03.008 |
| Key Words:high compression ratio turbulence kinetic energy air flow piston crown geometry tumble |
|
| 摘要点击次数: 4778 |
| 全文下载次数: 2154 |
| Abstract:Based on a 1.0 L turbocharged gasoline direct injection(GDI) engine, an engine model for 3D numerical simulation was set up and verified by the tested pressures in cylinder. The effects of different compression ratios(CR), different geometries and different structure sizes of piston on air flow in cylinder and turbulence kinetic energy(TKE) were simulated with the model at full throttle characteristics condition. The result shows that with the increase of CR, tumble becomes weak in compression process and TKE is reduced at the end of compression. TKE of CR 16.0 is 27% of that of CR 9.6. A relative larger bowl shape benefits the maintaining of higher TKE at the end of compression, and irregular shapes will reduce TKE by 41%. There exists the best structure size of the bowl, and too deep and too shallow pit will reduce TKE. In order to test the effect of the design of high compression ratio, the piston of CR 12.0 with the highest TKE was manufactured and tested at the lowest fuel consumption condition. Meanwhile, the simulation model was further verified. The effect of the piston on air flow in cylinder and TKE at different conditions was simulated, and the combustion characteristics of four CR 12.0 pistons with different bowl shapes were studied with the model at the lowest fuel consumption condition. The results show that the peak and phase of TKE change with the condition, but the effect of the piston top geometry on TKE has not changed, whether it is good or bad. Flame spreads in the direction of high TKE. The higher the TKE, the higher the flame spreading velocity and the better the combustion. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|