垂荡板对浮式风机水动—气动耦合性能影响研究

Effects of heave plate on coupling aero-hydrodynamic performances of floating offshore wind turbine

随着风电产业向深远海发展,浮式风机已经成为海上风机未来的发展趋势。由于复杂的风浪联合环境载荷作用,浮式风机作业时通常会产生大幅度的运动响应,这一方面会使得浮式风机系统受到的水动力载荷更加复杂,另一方面会影响浮式风机的输出功率。因此,如何有效地抑制浮式风机系统的运动响应就成为了设计的关键。基于非稳态致动线模型和两相流求解器naoeFOAM-SJTU,进行了带垂荡板的浮式风机耦合性能研究。首先在OC3-Hywind Spar平台上附加垂荡板,并结合NREL-5 MW风力机建立带垂荡板的浮式风机模型。其次对比不同形状的垂荡板对Spar-5 MW型浮式风机气动—水动耦合结果,分析相同风浪联合作用条件下垂荡板形状对浮式风机耦合响应的影响。研究结果表明:垂荡板能够减小纵荡和垂荡等运动响应幅值,但是对纵摇运动响应影响较小;当垂荡板直径和吃水位置相同时,相同风浪条件下圆形垂荡板能使浮式风机的气动平均功率增大约0.844%,而正方形垂荡板却使平均功率减小1.492%,这说明圆形垂荡板对浮式风机系统的作用效果整体而言优于正方形。

With the utilization of wind energy into the deeper water, the floating offshore wind turbine(FOWT) has become the trend of development of offshore wind turbine in the future. However, due to the complex environmental loads such as wind combined waves, the large motion responses are usually induced into the whole FOWT, which will increase the hydrodynamic load on the one hand and decrease the aerodynamic power on the other hand. Therefore, it is the key to effectively suppress the motion response of the floating platform. In this paper, based on the unsteady actuator model embedded in the two-phase flow solver, naoeFOAM-SJTU, the coupling performance of the FOWT with heave plate is studied. First of all, a FOWT with heave plate is studied based on OC3-Hywind Spar platform combined with NREL-5 MW wind turbine. Moreover, the influence of different shapes of heave plate on the aero-hydrodynamic coupling results of the FOWT is compared under the same wind and wave conditions. The results of research show that the surge and heave motions can be reduced by the heave plate, while they basically have no effect on the pitch motion. With the same equivalent diameter as the underwater part of Spar platform, draft, and environmental loads, the circular heave plate can increase the aerodynamic average power by about 0.844%. However, the square heave plate can reduce the average power by about 1.492%. It suggests the circular heave plate is better than the square shape.