波流及自由面对跨海桥隧预制结构水动力性能影响的数值分析

为提高静水和波流共同作用下的沉管和沉井浮运阻力计算效率，基于通用CFD软件StarCCM+和FLUENT及其二次开发，采用了包括叠模方法、VOF定常和非定常算法在内的几种水动力CFD计算方法并结合数值造波法，探讨了波流、自由面及流向角等因素对浮运阻力的影响.研究表明：对于静水计算，沉管可以忽略自由面的影响，沉井则不然；对于沉井，由于具有中空的内腔，VOF定常算法会抹掉由于初速影响产生的内部流体晃荡，而非定常算法则可以模拟出该晃荡现象.

Numerical Analysis of Effects of Wave,Current and Free Surface on Hydrodynamics of Sea-crossing Bridge and Tunnel Prefab Elements

In order to improve the computation efficiency of floating transportation drag of the caisson and immersed canal either in static water or in current and waves, a few CFD methods such as the double model method, VOF method including steady and unsteady methods, and numerical wave generation method were studied based on general CFD codes StarCCM+ and FLUENT and further development of FLUENT, which were used to discuss the effects of wave, current, free surface and inflow angle on the floating transportation drag. It is shown that for immersed canal in static water, the free surface can be neglected, while for caisson it cannot; for caisson with inner concavity, unsteady VOF method is necessary since steady method can conceal the sloshing of inner fluid due to the initial velocity.