目前政府推動再生能源，其中以太陽能熱水器的使用最為普遍，但由於台灣的地理位置，因常會發生颱風的自然災害，造成太陽能熱水器設備上的損害。而要有效降低太陽能熱水器之損害，除了加強太陽能熱水器結構強度之外，有效降低太陽能熱水器之升力與阻力是本研究之目標。
本研究使用Fluent 6.3.26商用軟體模擬太陽能板之 升、阻力，利用不同的紊流模式模擬找出與實驗值最接近的適合模擬為Standard k-ε模式，接著以Standard k-εmodel為基準，模擬60%模型不同的傾斜角與40%模型加裝不同的導流板之流場;但用60%模型在傾斜角為15度時，風洞內所占的阻塞比為8.35%，為了瞭解阻塞比但測試結果之影響，另模擬40%模型且傾斜角15度之案例，而40%模型所占的阻塞比為3.71%。
模擬結果指出，集熱板傾斜角越大，集熱板前端所受的壓力差越大。在集熱板加裝導流板時，可有效遮蔽氣流，避免氣流直接衝擊下板面，有效的降低集熱板前端的壓差，而導流板的截面積越大時，集熱板所受的升力隨之降低，但阻力隨之升高。

The government promotes the renewable energy resource recently to ease the tense situation of energy crisis. Among the available technologies of renewable energy, solar water heater is the most popular one in Taiwan. However, typhoons visit Taiwan several times a year and it may destroy the solar water heater. One of solution in regard to avoid the damage effectively is to reduce the lift force and drag force of the solar panel; and this is the major goal of this study.
The lift and drag forces of the solar water heater are simulated by a commercial software “Fluent 6.3.26” in this study. Several simulations with different turbulence models are completed to find out the model that provides the predictions fitting best with the experiment at results. Based on the fittest model, Standard k-εmodel, simulations of 60% scaled down solar water collector model with different tilt angles and 40% scaled down model with different guide plates are done in this study to investigate the effects of the tilt angle and guide plate. The blockage ratio of the wind tunnel for the 60% scaled down model with 15 degree tilt angle is 8.35% which for the 40% scaled down model with 15 degree tilt angle is 3.71%. The results of simulations prove that the larger tilt angle of the solar collector cause the larger pressure differences in the leading edge. Installation of the guide plate protects the solar collector by avoiding the flow directly hit the bottom surface of the solar collector; therefore it can efficiently reduce the leading edge pressure differences. Nevertheless, as the cross-sectional area of the guide plate increases, the lift force acted on solar collector decreases but the drag force would be increased.

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