船首外飘砰击设计载荷直接计算

文章结合三维线性势流理论和砰击速度的长期分析方法，求解出船体外飘位置的设计砰击速度；以首垂线和静水面交点处的设计砰击速度为目标值，给出了用于确定船首外飘砰击设计载荷的等效设计波，进而得到了设计状态下船体外飘剖面与波面相对运动关系；将船体剖面与波面间的相对运动关系等效转化为船体剖面与静水面的相对运动，利用显式有限元方法实现了外飘剖面砰击设计载荷的预报。针对直接计算方法中涉及的设计砰击速度、砰击压力和砰击压力系数，对比分析了文中结果和相应的规范值或试验值，论证了文中船舶外飘砰击压力设计载荷直接计算方法的合理性。

Direct calculation method of bowflare design slamming loads

The three-dimensional linear potential flow theory and long-term analysis method of relative slamming velocity are combined to determine the design impact velocity of bowflare structures; the design im-pact velocity of the location where the forward perpendicular and the static water surface intersect is set as the target value to calculate the equivalent design wave amplitude and the relative motion between the bowflare section and the wave surface in the design state; the relative motion between the hull flare section and the wave surface is equivalently transformed as that between the hull section and the static water sur-face; slamming pressure loads are gained by an explicit finite element method. The results such as design impact velocity, slamming pressure and slamming pressure coefficient are compared with those of the rule or experiments, and through analyzing the difference, the direct calculation method of bowflare design slam-ming pressure loads shows reasonable.