论文部分内容阅读
考虑半开口月池,研究桁架式Spar平台垂荡、纵摇、月池内流体垂向振动的耦合运动。建立了平台垂荡-纵摇-月池内流体垂向振动的耦合运动方程,推导了月池内流体对平台垂荡和纵摇运动产生的力和力矩。针对三种工况,即不考虑月池开口、月池开孔率为30%和70%,数值计算了耦合系统的运动响应,分析了月池内流体对平台垂荡和纵摇运动的影响,结果表明,月池内流体对平台主体垂荡有抑制作用,且抑制程度与月池开孔面积有关;对于70%的开孔率,平台垂荡响应RAO曲线在月池流体垂向振动固有周期附近出现高频峰值;70%开孔率时,月池内流体的运动远大于30%开孔率的情况;考虑月池开口后,平台的纵摇响应变化较小。最后,分析了耦合参数对平台及月池内流体运动的影响。
Considering the semi-open lunar pool, the coupling motion of the trussed Spar platform on the heave, pitch and the vertical vibration of fluid in the moonpool is studied. The coupled equations of motion of the vertical vibration of the fluid in the heave-pitch-moonpool are established and the forces and moments produced by the fluid in the moonpool on the heave and pitch motion of the platform are deduced. According to the three conditions, that is, irrespective of the opening of the moonpool, the opening rate of the moonpool is 30% and 70%, the motion response of the coupled system is numerically calculated, and the influence of the fluid in the moonpool on the heave and pitch motion of the platform is analyzed. The results show that the fluid in the moonpool has an inhibitory effect on the heave of the platform and the degree of inhibition is related to the open area of the moonpool. For the 70% open porosity, the RAO curve of the platform is near the natural period of the vertical vibration of the moonpool fluid When the opening of the moonpool is above 70%, the movement of the fluid in the moonpool is much larger than that of the 30% open hole. The change of the pitch response of the platform is small after considering the opening of the moonpool. Finally, the influence of coupling parameters on the fluid flow in the platform and moonpool is analyzed.