Advancement of Jensen (Park) wake model

Jensen model is one of the widely used wake models at the moment. The model is not only simple and easy to code, but also performs well on predicting wake loss. Instead of buying commercial wake model programs, Jensen model can be built easily in industrial and academic fields for themselves. Jensen model can be designed with programming tools, thus the model is compatible with other models and controllers. Wake decay coefficient, which is the main factor in Jensen model, is decided by turbulence intensity. Both turbulence and wake decay coefficient are increased in the wake. Jensen model was advanced for partial shadowing, however the model could not represent the wind turbine characteristics. Power is proportional to the cube and force is to the square of velocity. Wind speed for power and wind speed for force are calculated separately in this research. Yaw misalignment changes wind speed in the wake but it was neglected in Jensen model. An easy method is proposed to determine wind speed in yawed condition. Time delay between two wind turbines is required if wind speed changes. Duration between large wind turbines takes hundreds of seconds. Time delay is crucial in wake model validation. Three kinds of methods are compared to determine time delay. In the research, Jensen model is advanced for partial shadowing, yaw misalignment and non-constant wind condition. All the three topics are validated with measurement data.