为解决通航隧道断面受限导致的航行条件复杂问题，提升隧道的通航效率、经济性与安全性，综合考量断面尺度、通航安全与通过能力3大优化目标，聚焦通航隧道断面尺度优化及安全航速研究。首先，针对水下断面与水上断面，分别建立以船舶航速和建筑富余量为约束，以最小隧道水下断面系数、最小通航水深和最小隧道轮廓尺度为目标的多目标优化函数，并联合求解确定最优断面尺度；其次，在此基础上，为进一步优化隧道内水动力条件，设计消波块网箱式消波结构，并对其消波性能开展数值模拟分析；最后，基于优化断面和消波结构布置，构建2 000 t级船舶运动的三维数值模型，计算不同断面条件下的波高和流速，确定安全航速限值并建立船舶安全航速经验公式。结果表明： 1）所提出的断面优化方法可在满足通航安全与航行条件约束的前提下，确定通航隧道水下与水上断面的尺度； 2）布置消波结构后，数值模拟结果显示波高消减率为30.69%，流速消减率为51.34%，可有效改善水动力条件； 3）2 000 t级船舶在隧道水下宽度为15.20~25.20 m时的安全航速推荐为1.41~2.19 m/s，所建立的安全航速经验公式可用于该船型在不同断面尺度条件下的安全航速计算。
Navigable tunnels with small cross-sections can be difficult to navigate. To improve navigational and economic efficiency, and navigational safety, comprehensive multi-objective optimization models are established based on the cross-sectional dimensions, navigational safety, and navigational capacity. First, for above-water and underwater tunnel cross-sections, multi-objective optimization functions including the underwater cross-sectional coefficient, navigational water depth, and tunnel outline dimensions are constructed, which are restrained by ship speed and structural clearance, respectively. Subsequently, a block-cage wave dissipation structure is designed and evaluated through numerical simulations to optimize the hydrodynamic conditions in tunnels. Finally, a three-dimensional numerical model of a 2 000-t class ship is developed to calculate wave height and flow velocity under different cross-sectional conditions, determine safe navigation speed limits, and develop an empirical formula. The major results are as follows: (1) The proposed optimization method effectively predicts underwater and above-water tunnel cross-sectional dimensions under navigational constraints. (2) The wave dissipation structure reduces the wave height and flow velocity by 30.69% and 51.34%, respectively, effectively improving hydrodynamic conditions. (3) The recommended safe navigation speed is 1.41－2.19 m/s for a 2000-t class ship in underwater tunnels with widths of 15.20－25.20 m. The empirical formula is applicable to various cross-sectional dimensions.
