PIV和CFD在搅拌桨设计和优化中的应用

综述了激光粒子图像速度场仪(PIV)和计算流体力学(CFD)技术在搅拌桨设计和优化中的应用,阐述了PIV的实验测量基本原理及从平面PIV向三维PIV的发展趋势。目前,CFD数值模拟方法主要集中在雷诺平均方法(RANS)和大涡模拟方法(LES),而直接数值模拟方法由于物性模型精度以及计算量等原因尚难以工程化直接应用。通过CFD数值模拟方法和PIV实验方法验证,探究搅拌槽式反应器中速度场、剪切场、湍流动能耗散速率场等微观信息,进一步可以得到循环流量、平均剪切速率、搅拌功率、混合时间等宏观信息,这些结果将有助于对搅拌反应器中的流动与混合过程的深入剖析。随着高性能计算技术的发展,CFD数值模拟方法将会得到更大的应用,其与先进的三维PIV技术的耦合,将成为搅拌反应器设计与优化的重要方法。

Application of PIV and CFD in Impeller Design and Optimization

This paper reviews the laser particle image velocimetry （PIV） and computational fluid dynamics （CFD） technology, and its application progress on the impeller design and optimization. The basic measurement principle of PIV and its trend from the plane PIV to the three-dimensional PIV are discussed. CFD numerical simulation methods currently focused on Reynolds averaging method （RANS） and large eddy simulation （LES）, while direct numerical simulation method is still difficult to be used in engineering applications due to enormous computational effort and constitutive model reliability. CFD numerical simulation, verified by PIV experimental method, can explore the microscopic information in stirred tank reactors, velocity, shear field, turbulent kinetic energy dissipation rate field, etc. They can be further deduced to circulation flow number, average shear rate, stirring power, mixing time and other ic information. These results will contribute to the in-depth analysis of fluid flow and mixing processes in stirred reactor. With the development of high performance computing technology, CFD numerical simulation method will be got more applications coupled with advanced three- dimensional PIV technology, which becoming an important method for design and optimization of stirred reactor.