In this paper, wave scattering by an H-type porous barrier having nonlinear pressure drop boundary condition is analysed within the framework of small amplitude water wave theory. The H-type barrier is constructed using multiple thin (near zero thickness) rigid porous plates which are termed degenerate boundaries. The boundary value problem is solved using an iterative dual boundary element method. Different barrier configurations are analysed and compared to demonstrate the improved hydrodynamic performance of the H-type barrier. Further, the effect of porosity, relative spacing, the relative depth of submergence of the horizontal plate, wave steepness, and the rotation of the horizontal plate is investigated parametrically. Several results such as scattering coefficients (reflection, transmission, and energy-loss) and force coefficients (horizontal, vertical, and moment) are presented to understand the feasibility of the H-type barrier in real field applications. It is revealed that the increase in the structure porosity consistently increases the wave transmission, but reduces wave reflection, and force coefficients. Further, an increase in the relative spacing between the vertical barriers reduces the wave transmission by 20% without increasing the horizontal wave force but at the expense of increasing the vertical force coefficient in the shallow water regime. The results of this study are expected to be useful for the appropriate selection of different structure parameters to optimize the design.

本文在小振幅水波理论的框架内分析了具有非线性压降边界条件的H型多孔屏障的波散射。H 型屏障使用多个薄（接近零厚度）刚性多孔板构成，这些板被称为退化边界。边界值问题使用迭代双边界元方法求解。对不同的屏障配置进行了分析和比较，以证明 H 型屏障的改进的流体动力学性能。此外，参数化研究了孔隙度、相对间距、水平板的相对淹没深度、波陡度和水平板的旋转的影响。几种结果，例如散射系数（反射、透射、和能量损失）和力系数（水平、垂直和力矩）被呈现出来，以了解 H 型屏障在实际现场应用中的可行性。结果表明，结构孔隙度的增加持续增加了波的传输，但降低了波的反射和力系数。此外，垂直屏障之间的相对间距的增加将波浪传输减少了 20%，而不会增加水平波浪力，但代价是增加了浅水区的垂直力系数。预计本研究结果有助于合理选择不同的结构参数以优化设计。结果表明，结构孔隙度的增加持续增加了波的传输，但降低了波的反射和力系数。此外，垂直屏障之间的相对间距的增加将波浪传输减少了 20%，而不会增加水平波浪力，但代价是增加了浅水区的垂直力系数。预计本研究结果有助于合理选择不同的结构参数以优化设计。结果表明，结构孔隙度的增加持续增加了波的传输，但降低了波的反射和力系数。此外，垂直屏障之间的相对间距的增加将波浪传输减少了 20%，而不会增加水平波浪力，但代价是增加了浅水区的垂直力系数。预计本研究结果有助于合理选择不同的结构参数以优化设计。垂直屏障之间的相对间距的增加将波浪传输减少了 20%，而不会增加水平波浪力，但代价是增加了浅水区的垂直力系数。预计本研究结果有助于合理选择不同的结构参数以优化设计。垂直屏障之间的相对间距的增加将波浪传输减少了 20%，而不会增加水平波浪力，但代价是增加了浅水区的垂直力系数。预计本研究结果有助于合理选择不同的结构参数以优化设计。