摘要
针对流固耦合作用影响风力机的气动性能问题,基于CFX与ANSYS对风力机双向流固耦合模拟及未考虑耦合的风力机流场和结构场进行模拟,探究在额定工况下流固耦合作用对风力机输出功率影响情况.通过对比分析耦合前后的叶片表面压力分布、叶片的变形、风轮的扭矩进而研究风力机输出功率的变化.结果表明:考虑流固耦合作用时,风轮压力面的正压值基本不变,吸力面的负压值明显减小,叶片表面的压力差增大,而叶片在流固耦合作用下表面压力分布趋势无明显变化;叶片主要变形集中在靠近叶尖处,且越接近叶尖变形越大,呈非线性分布,叶片在流固耦合后的变形量相对未耦合增大,叶片的变形主要是沿着轴向的挥舞变形;且叶片的扭矩也更大,流固耦合作用下计算风力机输出功率为383 W,比未耦合增大1.6%,与试验值更接近.
Since fluid-structure interaction of wind turbine can affect its aerodynamic performance,two-way fluid-structure interaction simulations were carried out to analyze effects of the interaction on the output power of a wind turbine under the rated condition based on CFX and ANSYS. The pressure distribution on blade surface,blade deformation,torque on the rotor and output power are compared and analyzed before and after the fluid-structure interaction. The results show that under fluid-structure interaction conditions,the positive pressure on the pressure side remains unchanged basically,and the negative pressure on the suction side is significantly reduced,resulting in an increasedpressure difference across both sides. The pressure distributions on both the sides under fluid-structure interaction don't show a significant change from the case without fluid-structure interaction. The blade deformation mainly occurs near the blade tip,and increases nonlinearly towards the tip. Furthermore,the deformation is intensified in fluid-structure interaction,and mainly is waving deformation along the axial direction. The torque is larger in fluid-structure interaction,in consequence,the wind turbine output power arises by 1. 6% to reach 383 W compared with the case without fluid-structure interaction,which is much closer than its experimental value.
引文
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