For the new sandglass-type floating body with special shape, this paper mainly analyzes the characteristic of the heave damping and its corresponding components by computational fluid dynamics (CFD) method. Firstly, the convergence and accuracy of the CFD method to simulate the heave motion of sandglass-type floating body were validated along with the experimental data. Secondly, the numerical model of the floating body with forced heave motion was created, and then hydrodynamic forces versus different motion amplitudes were calculated and compared to discuss its nonlinear characteristics. Afterwards, based on time-history curves of the hydrodynamic force, heaving added mass and damping of the floating body versus various frequencies were achieved and found to be different from the potential results. In order to analyze the reasons that cause difference, numerical simulations using inviscid and k-ε turbulent models were performed respectively, and the results indicate that the effect of fluid viscosity on the hydrodynamic coefficients is small and not decisive. Then equivalent radiation damping based on CFD wave elevation was deduced to explore the relation between the inviscid CFD and potential models. Finally, local wave field and vorticity field near the body were mainly discussed, and quantitative analysis based on mechanical energy was performed to verify that the vortex due to the body shape is the essential cause of the heave damping for the sandglass-type floating body.

对于新型的特殊形状的沙漏型浮体，本文主要通过计算流体力学（CFD）方法来分析升沉阻尼的特性及其对应的分量。首先，结合实验数据验证了CFD方法在模拟沙漏型浮体升沉运动中的收敛性和准确性。其次，建立了具有强迫升沉运动的浮体的数值模型，然后计算了流体动力与不同运动幅度的关系，并进行了比较，以讨论其非线性特性。然后，基于流体动力的时间-历史曲线，获得了浮力的增加质量和浮体相对于各种频率的阻尼，发现与潜在结果不同。分别建立了k-ε湍流模型，结果表明流体粘度对流体动力系数的影响很小，没有决定性作用。然后推导了基于CFD波高程的等效辐射阻尼，以探索无粘性CFD与势能模型之间的关系。最后，主要讨论了人体附近的局部波场和涡度场，并进行了基于机械能的定量分析，以验证由于体形引起的涡旋是沙漏型浮体起伏阻尼的必要原因。