Comparison two wake models based on full geometry turbine and actuator disc theory and study the effect of blockage

Two numerical wake model were established, one based on full geometry turbine and one based on actuator disc theory. The Actuator disc momentum theory assumes turbine as a constant sink of momentum in numerical domain. Results of numerical models were compared with experimental results, the experimental data is in good agreement with the simulation data. The difference between two models were analyzed in detail. The the difference between simulation results of actuator disc and test results are slightly larger in near wake region, the difference gradually decreased as the axial distance increased. The lack of the simulation of rotation of the model may lead this difference. The effect to wake recovery of blockage ratio was studied using numerical model based on actuator disc theory, 11 cases were studied, the results showed that the blockage ratio can heavily effect the recovery speed of turbine wake. Along the centerline, the degree of wake recovery decreased as the blockage ratio increased before X/D=10.8, and the degree of wake recovery increased as the blockage ratio increased after X/D=10.8.