Analysis of Wake Interference Between Wind Turbines in a Wind Farm Using ANSYS CFX<br />Dr. Firas Thair Al-Maliky<br /><br />The efficient operation of wind farms is significantly influenced by the aerodynamic interaction between individual wind turbines, particularly through wake effects. The wake generated by an upstream turbine causes a velocity deficit and increased turbulence intensity in the flow downstream, which can reduce the performance and accelerate the fatigue of downstream turbines. Understanding and mitigating wake interference is crucial for optimizing wind farm layouts and enhancing energy capture.<br /><br />This study presents a computational fluid dynamics (CFD) analysis of wake interference between wind turbines using ANSYS CFX, a powerful tool for simulating complex fluid flow phenomena. The focus is on quantifying the velocity deficit, turbulence intensity, and power loss experienced by downstream turbines under various spacing arrangements and wind conditions.<br /><br />A detailed 3D model of a typical horizontal-axis wind turbine was constructed, including rotor blades, nacelle, and tower. The turbine’s rotating blades were modeled using the Multiple Reference Frame (MRF) approach to simulate steady-state rotor effects. The computational domain represented a section of the wind farm with two turbines aligned along the wind direction at varying distances.<br /><br />Simulations were conducted under different inlet wind speeds and turbulence intensities to replicate realistic atmospheric conditions. The results showed that wake velocity deficit could reduce the effective wind speed at the downstream turbine by up to 25% for closely spaced turbines (3-5 rotor diameters apart). This velocity reduction corresponded to a power output drop of approximately 15-20%.<br /><br />Flow visualization revealed the formation of complex vortices and increased turbulence intensity in the wake region, contributing to unsteady aerodynamic loads on downstream blades. Increasing the spacing between turbines significantly reduced wake interference, improving downstream performance and reducing structural fatigue risks.<br /><br />The study also examined the effect of yaw misalignment as a potential wake steering strategy, demonstrating that intentional yawing of upstream turbines could deflect wakes and partially recover downstream wind speeds.<br /><br />In conclusion, ANSYS CFX-based CFD analysis provides valuable insights into wake dynamics and turbine interactions within wind farms. Optimizing turbine spacing and employing advanced control strategies such as wake steering are essential to maximize wind farm efficiency and reliability. This research supports the advancement of sustainable wind energy systems by guiding better design and operational practices in wind farm development.<br /><br /><br />Al-Mustaqbal University – The No. 1 Private University in Iraq