凹腔几何构型和来流马赫数对部分覆盖型凹腔流动的影响

Effects of Geometric Parameters and Incoming Flow Ma on Flow Characteristics of Partly-covered Cavities

关键词:  凹腔  部分覆盖  几何构型  马赫数  质量交换 

Key words:  Cavity  Partly-covered  Geometric parameter  Mach number  Mass exchange

摘要:

为了研究覆盖板长度、凹腔深度、凹腔长深比和来流马赫数对部分覆盖型凹腔流场的影响,采用二维耦合隐式N-S方程和标准k-ε湍流模型,对部分覆盖型凹腔的流场进行了数值仿真。发现覆盖板长度对自由来流没有明显影响；长深比是影响不同深度凹腔的覆盖区质量交换的主要因素；覆盖区质量交换随着长深比增大而减少；来流马赫数增加,凹腔覆盖区的质量交换下降；与大长深比凹腔相比,小长深比凹腔的覆盖区质量交换受长深比和来流马赫数影响更加明显。 

Abstract:

To investigate the effects of cover-plane length, cavity depth, ratio of length to depth(L/D for short) and free stream Ma on the partly-covered cavity flow field, two-dimensional coupled implicit N-S equations and standard k-ε turbulent flow models were used to simulate the partly-covered cavity flow field. It is found that the cover-plane length does not have evident effect on the free stream. The L/D of cavity is the main factor which affects the mass exchange of covered region in the cavities with different cavity-depth. The mass exchange of covered-region decreases as the L/D of cavities increases. As the Ma of free stream increases, the mass exchange of covered-region decreases. Compared with the cavities with large L/D, the covered-region mass exchange is more sensetive to L/D and free stream Ma in the cavities with small L/D.