基于粘性无粘耦合的风力机流场致动体模型研究

The Actuator Model is capable of computing the three-dimensional flow field of wind turbine efficiently, which provides an effective tool for the study of the wind turbine aerodynamics and wake development. However, due to the oversimplication of the blade geometry, the deviation of the bodyforce computation and its distribution, currently the Actuator Disc, Actuator Line and Actuator Surface Models may inevitably introduce computational errors. Based on the idea that the flow can divided into viscous and potential aeras, Viscous and Inviscid Interaction (VII) Method computes different aeras separately and the full-domain result is obtained form the interaction between these two parts. The VII model makes the surface force computation around three-dimensional geometry of wind turbine blade fast and accurate, which provides the opportunity to construct the Actuator Body Model. But the following difficulties are still needed to be solved: (1) the flow separation may cause the divergence of VII model, (2) in the actuator model the simulation of the Atmospheric Boundary Layer (ABL) is very expensive, (3) how the flow information transfer between VII and actuator models is not clear. In this application the solution to these problems will be studied, including: (1)creat the viscous and inviscid interaction mechanism under complex flow condition, to improve the computational ability of VII model when the flow separation occurs. (2) modify the viscous tensor at the ground surfave boundary to simulate the no-slip boundary condition for the computation of the ABL. (3) based on the single- and dual-feedback mode to construct the flow information transfer models for the Actuator Body Model, and testify the capability of these models according to the efficiency and accuracy. The creation of Actuator Body Model will provide an important research platform for the study of wind turbine three-dimensional flow field.

致动模型可以快速计算复杂三维流场，为风力机气动及尾流研究提供有效手段。但目前致动盘、线、面模型对叶片几何外形过度简化、体积力源项计算及分布形式过于粗糙，导致从源头上引入了计算误差。粘性无粘耦合模型以叶片三维几何外形为基础，基于流场粘性-势流分区、耦合求解思想实现叶片表面力分布的快速计算，为构造更加准确的致动体模型提供了条件。但该模型的建立仍面临以下问题：1、流动分离导致粘性无粘耦合模型发散；2、致动模型中大气边界层模拟耗费巨大计算资源；3、不同数值模型间流场信息传递困难。本申请拟从以下方面展开研究：1、研究复杂工况下粘性无粘耦合模式，解决流动分离工况的模拟问题；2、依托大气地表边界粘性应力张量，近似模拟地表无滑移条件，提高计算速度；3、以单、双反馈模式构建致动体模型的流场信息传递机制，以计算效率和精度为基准检验不同机制的分析能力。致动体模型的建立将为风力机三维流场研究提供重要的数值工具。

致动模型可以快速计算复杂三维流场，为风力机气动及尾流研究提供有效手段。但目前致动盘、线、面模型对叶片几何外形过度简化、体积力源项计算及分布形式过于粗糙，导致从源头上引入了计算误差。粘性无粘耦合模型以叶片三维几何外形为基础，基于流场粘性-势流分区、耦合求解思想实现叶片表面力分布的快速计算，为构造更加准确的致动体模型提供了条件。但该模型的建立仍面临以下问题：1、流动分离导致粘性无粘耦合模型发散；2、致动模型中大气边界层模拟耗费巨大计算资源；3、不同数值模型间流场信息传递困难。本申请拟从以下方面展开研究：1、研究复杂工况下粘性无粘耦合模式，解决流动分离工况的模拟问题；2、依托大气地表边界粘性应力张量，近似模拟地表无滑移条件，提高计算速度；3、以单、双反馈模式构建致动体模型的流场信息传递机制，以计算效率和精度为基准检验不同机制的分析能力。致动体模型的建立将为风力机三维流场研究提供重要的数值工具。