Investigation of the wake blending of wind turbines with different capacities in a tandem configuration using LES

With the rapid development of wind power generation technology, the size and capacity of wind turbines are increasing rapidly. In order to optimize the utilization of wind resources, early wind farms may require to be retrofitted and upgraded alongside new wind farm development. During this process, replacing some old or faulty wind turbines with new models becomes necessary. In this study, large eddy simulation and actuator line model were used to study the influence of different combinations of wind turbines with varying capacities and spacing on wake characteristics in a tandem configuration. The results show that downstream small-capacity wind turbines contribute to increased velocity deficit and fluctuations in the wake region, thus influencing wake recovery. Moreover, increasing the spacing between wind turbines shifts the downstream turbines' effect on wake recovery from positive to negative, and the increase in downstream wind turbine capacity amplifies the above-mentioned impact.