动态来流及塔影效应对风力机尾迹特性影响研究

Study on Influence of Dynamic Inflow and Tower Shadow Effect on Wake Characteristics of Wind Turbines

台风是风力发电机组的主要故障因素之一。针对正常风况和极端风况进行了UDF建模,得到的动态来流模型还考虑了阵风及极端风向变化情况,基于FLUENT采用滑移网格技术和RNG研究了动态来流及塔影效应对风力机下游尾迹特性的影响。结果表明:通过UDF编译的动态来流与理论值完全吻合,验证了UDF的正确性;风机前端来流的随机波动会引起风力发电机输出功率波动,尾迹结构出现形变。此外,扭矩以及功率受风机塔影效应影响而下降,塔架表面升力突变,进而影响塔架疲劳寿命。数值计算的结果对风力机组结构设计和风电场机组阵列分析具有重要参考价值。

Typhoon is one of the main factors lead to failure of wind turbines.Normal wind condition and extreme wind condition are modeling by UDF.Dynamic inflow model was built while gusty wind and extreme wind direction changing were considered.Based on FLUENT,sliding grid technology and RNG,the effects of dynamic incoming flow and tower shadow effect on the downstream wake characteristics of wind turbines are studied.The results show that the dynamic inflow compiled by UDF is in good agreement with the theoretical value,which verifies the correctness of UDF.The power output of wind turbines fluctuates with the changing of dynamic inflow.Deformation of wake geometry was also observed.The decreasing of torque and power of wind turbines was caused by tower shadow effect,which makes the lift of tower surface change sharply,and fatigues the tower.Life expectancy has a negative impact.The results of numerical calculation have important reference value for the structural design of wind turbine units and the array analysis of wind farm units.