基于OpenFOAM的喷孔内部流动与近场雾化的数值模拟

Numerical Simulation of Internal Flow of Nozzles and Near-field Sprary with OpenFOAM

基于OpenFOAM平台,对Schnerr-Sauer空化模型的蒸发和凝结源项进行了修正,建立了一种考虑热力学效应的空化模型,并分别采用原始模型和修正空化模型对燃油在喷孔内部的流动及喷嘴近场的雾化过程进行了模拟计算。修正空化模型与原始模型相比,喷孔内部的空化强度加强,空穴范围扩大,喷孔近场区域的未扰液核变短,燃油分裂雾化更加细小,说明修正空化模型促进燃油的初次分裂及雾化。

A revised cavitation model was established considering thermal effect with modified evaporation and condensation source terms, which was based on Schnerr-Sauer cavitation model of OpenFOAM toolbox. The computations for the fuel atomization process of the orifices and near noz- zles were conducted by original Schnerr-Sauer cavitation model and revised cavitation model respec- tively. The nozzle of revised cavitation model is more intense than that of original Schnerr-Sauer mod- el, and the area of cavitation is wider than that of original Schnerr-Sauer model. Simultaneously, the length of unperturbed liquid core of the near nozzle region is shorter and atomization of the fuel is smaller. It is dictated that the revised cavitation model can accelerate the fuel break-up and atomization.