不同来流条件下旋转圆球绕流特性研究与非定常气动模型构建

颗粒与流场的相互作用是广泛存在于自然界和工程中的气固两相流问题。颗粒运动往往伴随自身旋转，一方面旋转导致的升力引起颗粒产生侧向迁移运动，另一方面旋转会影响颗粒的绕流特性以及改变拖曳力大小，因此对旋转颗粒的绕流问题进行深入研究十分必要。尽管近年来已有针对均匀来流中旋转圆球颗粒绕流的研究，但所考虑的参数范围比较有限，未考虑更复杂来流条件的影响，并且缺乏颗粒所受气动力脉动的定量预测模型。为此，本课题拟以CFD模拟为技术手段，研究不同来流条件下旋转圆球颗粒绕流特性和非定常气动力特性，构建旋转圆球颗粒在不同来流条件下的非定常气动力模型。本课题所考虑的来流条件包括均匀来流、剪切来流和非定常来流，其中非定常来流由单个或多个正弦波合成得到。本课题研究将有助于获得颗粒对湍流调制作用的进一步认识，以及适用于复杂流动环境中的颗粒非定常气动力模型。

The interaction between particle and fluid flow is an important gas-solid two-phase flow problem which exists widely in nature and engineering applications. The translating motion of particle always accompanies with rotation, that may lead to lateral migration and influence the surrounding flow pattern and drag force. Thus, it is extremely essential to study the problem of flow past rotating sphere particle. Although there are some studies concerning the problem of rotating sphere in uniform flows, the parameters and freestream conditions they considered are limited, and there is a lack in quantitative model for unsteady aerodynamics of particle. According to this, this project aims to study the flow past rotating sphere under different freestream conditions using CFD method, and construct unsteady aerodynamic model for the particle. The different freestream conditions include uniform flow, shear flow and unsteady flow, and the unsteady flow is composed of one or several sinusoidal waves. It can be conductive to obtain further understanding of particle-turbulent modulation and unsteady aerodynamic model applicable in complex flow environment from this project.