一种改进的直喷汽油机涡旋喷油器油束模型

An Improved Spray Model of High Pressure Swirl Injector in GDI Engine

根据燃油薄膜模型和表面波破碎理论,在KIVA3程序的基础上建立了适合于计算缸内直喷汽油机高压涡旋喷油器油束特性的模型。对原模型进行了改进和简化,并加入了初始喷雾的计算模块。采用该模型可以计算出油束特性的主要参数,包括主喷雾和初始喷雾的贯穿度、油束索特平均直径(SMD)等,并应用此模型计算了高压涡旋喷油器在两种不同工况下的油束外形结构和油束特性参数。模拟计算结果表明,经过改进的油束模型可以准确地计算出燃油薄膜参数(包括薄膜厚度和速度);通过引入初始喷雾,使喷雾外形和索特平均直径的模拟计算结果与试验结果更加吻合。

Based on liquid sheet model, surface wave breakup theory, a spray model was developed for GDI engine high pressure swirl injector using a modified version of a KIVA3 code. A previously developed sheet atomization model was modified and simplified, and an initial spray slug module was introduced into calculation. This model can be used to calculate the main spray characteristics parameters such as the initial spray, main spray penetration and the overall Sauter mean diameter(SMD). The spray structures and spray characteristic parameters were simulated for two different operating cases. The simulations show that the improved spray model can accurately estimate the sheet parameters including sheet thickness and velocity, the computed results of the spray structures and overall SMD agree better with the experimental results through introducing the initial spray slug than the previous spray model.