Boundary layer instability beneath internal solitary waves (ISWs) of depression may be a significant source of wave-energy dissipation and drive localized mixing and resuspension in coastal regions. Wave flume experiments were undertaken to measure the dissipation of turbulent kinetic energy in the boundary layer beneath ISWs shoaling over a flat bottom. The rate of dissipation of turbulent kinetic energy $(\varepsilon \sim {10}^{-7}-{10}^{-2}\mathrm{W}\mathrm{k}{\mathrm{g}}^{-1})$ was elevated within the unstable boundary layer region, occurring for waves with momentum thickness-based Reynolds number ${\mathrm{Re}}_{ISW}>\sim 200$. Dissipation was parametrized in terms of wave energy $(\mathrm{RMSE}=10\times {10}^{-4}\mathrm{W}{\mathrm{m}}^{-1})$ and ${\mathrm{Re}}_{ISW}$ $(\mathrm{RMSE}=7\times {10}^{-4}\mathrm{W}{\mathrm{m}}^{-1})$. The dissipation length scale was computed from wave-integrated boundary layer dissipation $L_d=\frac{cE}{D}$ and parametrized as a function of wavelength $\lambda$ and ${\mathrm{Re}}_{ISW}$ as ${L_d}^{*}=100\lambda +2.5\times {10}^{10}\lambda {\mathrm{Re}}_{ISW}^{-3.7}$ $(\mathrm{RMSE}=\sim 50\lambda )$. Unstable waves had a dissipative length scale of $\sim 100\lambda$, in agreement with limited field observations, whereas stable waves propagated significantly further $(>\sim 1000\lambda )$.

中文翻译：

---

内部孤立波底部边界层耗散

凹陷内部孤立波 (ISW) 下的边界层不稳定性可能是波能耗散的重要来源，并驱动沿海地区的局部混合和再悬浮。进行了波浪水槽实验以测量在平底浅滩上的 ISW 下方边界层中湍流动能的耗散。湍动能耗散率$(\varepsilon ～{10}^{-7}-{10}^{-2}\mathrm{宽}\mathrm{克}{\mathrm{G}}^{-1})$ 在不稳定边界层区域内升高，发生在具有基于动量厚度的雷诺数的波中 ${\mathrm{关于}}_{\mathrm{一世}秒宽}>～200$. 耗散是根据波浪能参数化的$(\mathrm{均方根误差}=10\times {10}^{-4}\mathrm{宽}{\mathrm{米}}^{-1})$ 和 ${\mathrm{关于}}_{\mathrm{一世}秒宽}$ $(\mathrm{均方根误差}=7\times {10}^{-4}\mathrm{宽}{\mathrm{米}}^{-1})$. 耗散长度尺度由波浪积分边界层耗散计算${升}_d=\frac{C乙}{D}$ 并参数化为波长的函数 $\lambda$ 和 ${\mathrm{关于}}_{\mathrm{一世}秒宽}$ 作为 ${{升}_d}^{*}=100\lambda +2.5\times {10}^{10}\lambda {\mathrm{关于}}_{\mathrm{一世}秒宽}^{-3.7}$ $(\mathrm{均方根误差}=～50\lambda )$. 不稳定波的耗散长度尺度为$～100\lambda$，与有限的实地观察一致，而稳定波传播得更远 $(>～1000\lambda )$.