引射比对生物柴油斯特林发动机喷雾特性影响的仿真研究

基于斯特林发动机的喷雾特性,建立了某斯特林发动机旋流引射、喷雾的数学物理模型,模拟了高背压下生物柴油斯特林发动机在不同引射比下的喷雾过程。研究发现:生物柴油喷雾锥角随引射比的增大而增大,大引射比下的喷雾油束前端出现了明显的凹型回缩锋面;引射比越大,喷雾贯穿距越小;增大引射比,液滴速度增大,索特平均直径减小,粒径方差减小。高背压下,增大引射比能增大燃油混合气的空间分布,提高喷雾雾化效果。

Simulation Study of Ejection Ratio on Spray Characteristics ofa Stirling Engine by Using Biodiesel

Based on the spray characteristics of the Stirling engine, the mathematical physics model of the swirl injection and spray of a Stirling engine was established, and the spray process of the biodiesel Stirling engine at different ejection ratios was simulated. The results show that the spray cone angle increases with the increase of the ejection ratio, and the front end of the spray oil bundle has a large concave retraction front at the large ejection ratio; the larger the ejection ratio, the smaller the spray penetration distance; increasing the ejection ratio,the droplet velocity is increased, the Sauter mean diameter is reduced, and the particle size variance of spray droplets is reduced. Under high back pressure, increasing the ejection ratio can increase the spatial distribution of the fuel mixture and improve the spray atomization.