横向紊动射流的数值与实验研究进展

横向紊动射流作为流体运动的一种重要类型,广泛存在于如: 燃气轮机气膜冷却、锅炉燃烧 室等的燃烧控制, V/STOL(垂直或短距离起落)飞机、废气排放的控制等工程实际应用中. 由于射流的存在,增加了流场的复杂性,流场中同时存在射流剪切层涡、马蹄形涡系、反向 旋涡对和尾迹涡等4种涡系结构,这对流体力学理论研究具有重要意义.长期以来,研究人 员从理论分析、实验测量和数值模拟方面对横向紊动射流进行了大量的研究工作,目前已经 认识了流场中的许多流动特性和流动机理.从数值模拟和实验研究两个方面,比较并分 析了国内外横向紊动射流研究的现状和研究结果,评述了不同湍流模型以及不同的实验测量 方法对横向紊动射流的预测能力,讨论了存在的问题并对该领域的研究方向进行了展望.

NUMERICAL AND EXPERIMENTAL PROGRESSES OF THE RESEARCH ON THE JETS IN CROSSFLOW

A turbulent jet turning transversely into a uniform crossflow is an important type of fluid flow with applications in various engineering fields, e.g. internal film cooling of turbine blades, dilute air jets in combustion chambers, jet from V/STOL aircraft in transition flight, and waste disposal from smoke stacks into the atmosphere. The jet in a crossflow is a highly complex turbulent flow due to the action of many structures in the field, including the jet shear-layer vortices, the system of horseshoe vortices, the counter-rotating vortex pair, and the wake vortices. These phenomena have been observed in number of previous investigations in theoretical, experimental and numerical studies, and some structural features and flowing mechanisms have been revealed. In this paper, from the aspects of the numerical simulation and the experimental research, the present research methods and results are analyzed, and the forecasting ability of both the different turbulence models and various measuring ways are summarized. In the end, some unsettled issues are discussed and the developing directions in this field are also pointed out.