Combustion performance experiments were carried out on a single-cylinder diesel engine to study the influences of a lateral swirl combustion system(LSCS)and a multi-swirl combustion system(MSCS)on engine performance. Combined with simulation analysis,the fuel-air mixing and combustion characteristics were revealed for the LSCS and the MSCS respectively. Experimental results show that under low loads and high excess air coefficients,the MSCS obtains better combustion performance than the LSCS with the maximum reduction in fuel consumption of 3.6g/(kW•h),in soot emission of 0.13g/(kW•h)and in combustion duration of 2.6°CA. However,under heavy loads and low excess air coefficients,the LSCS shows better combustion performance than the MSCS with the maximum reduction in fuel consumption of 2.6g/(kW•h),in soot emission of 0.56g/(kW•h)and in combustion duration of 2.8°CA. Simulation results indicate that,when the engine load decreases or the excess air coefficient increases,the fuel spray penetration ability becomes weakened,and the circular ridge of the MSCS chamber improves fuel-air mixing quality more effectively. However,when the engine load increases or the excess air coefficient decreases,the fuel spray penetration ability is enhanced. The split-flow creation of the LSCS chamber improves the fuel-air mixing quality more evidently,while the circular ridge of the MSCS chamber hinders the diffusion of fuel spray.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |