垂直軸式層狀型風力發電系？i之研製-子計畫一：垂直軸式層狀風力發電機氣動力設計與實驗之研究(II)

Abstract

本計畫係發展一新型垂直式風機，此風機結合了升力型及阻力型風機的優點，並 可將數個風機葉輪堆疊以得到較大的輸出功率。為了解其氣動特性及風場結構，將利 用計算流力的方法做全場式的數值模擬，數值方法將採用近幾年來我們所發展的非結 構性網格有限體積法，為處理風場葉片的旋轉，將採用多重參考座標系統，對於其紊 流性質，將採用渦流黏滯模式。將針對各種參數，如風速、轉速、風機位置角度、堆 疊層數等進行測試，以了解其對風輪葉片流道內的流場構造及尾流結構的影響，進而 能改善其設計。此外亦將進行實驗配合，量測風機葉片的壓力及其所產生的扭力，以 驗證數值計算的準確性。

A new type of vertical axis wind turbine is developed in this project. This new design combines the merits of the lift type and drag type of wind turbines. It also possesses a feature by which several turbine wheels can be stacked together to get higher output power. The method of computational fluid dynamics is used to make full 3-D simulation to investigate into flow fields and aerodynamic characteristics. The numerical scheme is based on a finite volume method, developed by our group, capable of using unstructured grids. The multi-frame of surface is adopted to tackle the rotation of the turbine wheel. The turbulent characteristics of the flow field are modeled using the eddy viscosity model. A variable of parameters such as the wind speed, the rotational speed, the position angle of the rotor and the number of the turbine wheels etc. will be tested to find their effects on the flows in the channels of the turbine wheel and on the wakes behind the turbine. Based on this understanding, the design will be improved to obtain higher performance. In addition, experiments will be conducted to measure the pressure distribution on the turbine blades and the torque generated. This information becomes valuable to validate the numerical calculations.