摘要
利用三维分析软件AVL-FIRE对OPOC发动机在不同工况下的二冲程全周期三维瞬态工作循环(自由排气、扫气、过后充气、压缩、燃烧和膨胀做功)进行分析,研究了全周期循环过程中不同转速下的扫气质量、气体流动、混合气形成与燃烧以及排放物的生成等瞬态变化规律。分析表明,随着转速的升高,扫气效率和给气比逐渐降低,捕获率增加,最大气缸压力不断减小,缸内平均温度在换气过程和膨胀过程中随转速的升高而升高,在燃烧过程中随转速变化不大。NO的生成量随着转速的升高而降低,Soot的生成峰值也随着转速的升高而降低,但是由于受到氧化作用,Soot的最终生成量随转速的升高而升高。
By using three-dimensional numerical simulation software AVL-FIRE to simulate the two stroke three-dimensional transient cycle（including free exhaust, scavenging, after inflation, compression, combustion and expansion） of the OPOC engine in different working conditions, this paper investigates the transient changing law of the cycle under different speed, including sweep gas quality, gas flow, mixture formation and combustion and emissions generation. Analysis showed： with the increase of the rotating speed, the scavenging efficiency and the delivery ratio decreased gradually, the capture rate increased, and the maximum cylinder pressure decreased. The average temperature in the cylinder increases with the increase of the rotating speed in the process of sweeping gas and expansion, while it does not vary with the speed in the process of combustion. The mean NO mass fraction decreases with the increase of rotational speed, the maximum mass fraction of Soot also decreases with the increase of rotational speed. But due to oxidation, the final mean Soot mass fraction increases with the increase of rotational speed.
出处
《内燃机》
2016年第6期27-30,33,共5页
Internal Combustion Engines
关键词
对置活塞
对置气缸发动机
循环
扫气
燃烧
排放
opposed piston
opposed cylinder engine
working cycle
sweep gas
combustion
emission
