湍浮力射流形成后区特性的预报

应用作者所提出的数学模型和计算方法,对浮力射流形成后区的特性进行了预报。得出中性浮力点以前的形成后区,可分为非浮力区、过渡区和卷流区。得到了非浮力区和卷流区的时均流速、时均温差、雷诺切应力、湍动能及其耗散率的分布和湍动能的平衡。这些预报结果与试验资料基本吻合。

Prediction of the Characteristics for ZEF of Buoyant Jets

The mathematical model and calculational method of buoyant jets given by authors are used to predict the characteristics of the zone of established flow. The calculation of the centerline velocity and temperature is made for a wide range of exit Froude number and environment stratification. A unified scaling law is used for normalization of these results. The correlation of the predicted results shows that the established zone of the buoyant jet may be divided into three regions: nonbuoyant region, intermediate region and plume region.The mean velocity, mean temperature difference, Reynolds stress, turbulent kinetic energy and its dissipation are computed for the nonbuoyant region and the plume region. The turbulent kinetic energy balance of the two regions is also predicted. A good agreement between the predicted results and the available experimental data is obtained.