CFD数值模拟在微涡絮凝中的应用

Application of CFD numerical simulation in micro-vortex flocculation

传统的絮凝理论是基于层流的条件得到的结果,而实际絮凝反应中,流体的流态是以湍流占优势的,不存在整体和恒定不变的速度梯度,因此微涡絮凝较传统絮凝更为复杂,其内部流态分布对絮体的形成具有重要作用,但目前试验无法获取其流态分布。随着计算机硬件的更新,计算能力不断提高,许多学者开始使用CFD数值模拟对种种复杂的实际问题进行计算模拟,以湍动能k、湍动能耗散率ε、涡旋速度梯度、涡旋尺寸作为评价指标,对微涡絮凝进行研究。

The traditional flocculation theory is based on the conditions of laminar flow, which is relatively mature. In the actual flocculation reaction, the fluid flow state is dominated by turbulent flow, not laminar flow, and there is no overall and constant velocity. Gradient, therefore, micro-vortex flocculation is more complicated than traditional flocculation, and its internal fluid state distribution plays an important role in the formation of flocs, but the current flow state distribution cannot be obtained. In recent years,with the updating of computer hardware, the computing power has been continuously improved. Many scholars have begun to use CFD numerical simulation to calculate and simulate various complex practical problems, such as turbulent energy k, turbulent energy dissipation rate ε, vortex velocity gradient, vortex Spin size was used as an evaluation index to study micro-vortex flocculation.