三种湍流模型对导管螺旋桨空化性能计算的比较

摘要

The cavitation performance of ducted propellers is simulated by employing a Rayleigh-Plesset cavitation model and three turbulence models resorting to the computational fluid dynamics(CFD)soft⁃ware. A comparison between the calculated results and experimental data reveals the detailed effects of dif⁃ferent turbulence models and cavitation numbers. The results show that the k - ω model has better conver⁃gence and is more stable and accurate than the k - ε model and the RNG k - ε model,which suggests the k - ω model to be the most ideal in evaluating the cavitation performance of ducted propellers. However, when the cavitation number or the advance coefficient is small,the cavitation will become relatively severe and the calculation errors may increase for the k - ω model,since the k - ω model is more sensitive to the cavitation number compared with the other two. Thus,a more accurate cavitation model or a better qual⁃ity of the mesh is required.%　　借助 CFD 软件，采用 Rayleigh-Plesset 空化模型和三种湍流模型对导管螺旋桨进行不同空化数条件下的空化性能计算，通过与试验数据对比，分析不同湍流模型、不同空化数对计算结果的影响。分析结果表明：k -ω模型计算更加稳定，更加容易收敛，精度也相对较高，因而与 k -ε模型和 RNG k -ε模型相比更适于对导管螺旋桨的空化性能进行计算；在空化数或进速系数较小的条件下，空化相对较剧烈，计算的相对误差较大，需要采用更加精确的空化模型或通过进一步提高网格质量来提高计算精度；另外，与 k -ε模型和 RNG k -ε模型相比，k -ω模型对空化数较敏感，对不同空化数条件下计算的相对误差变化较大。