CFD在高速滑行表面性能预报中的应用

Application of CFD in predicting performance of high-speed planing hulls

针对滑行表面数值预报结果中船底出现异常水气分布的问题,基于三种常用CFD软件FLUENT、CFX及STAR-CCM+研究了VOF界面插值格式、网格类型及数目等因素对滑行表面性能数值预报的影响,并提出相应改善数值计算模拟的具体措施。研究表明:基于相同的结构化网格及计算设置时,采用几何重构界面插值格式预报滑行块的阻力及底部水气分布上最为准确,CICSAM格式次之,修正HRIC格式最弱。通过选择合理的网格类型及网格数目也可以改善滑行船体性能预报精度。CFX采用四面体网格,STAR-CCM+采用多面体网格可以较为准确预报滑行艇体的流场和阻力。建议在滑行艇的阻力及流场预报中采用几何重构的VOF界面插值方式,选择合理的网格类型并进行适当的网格加密可以提高水气界面捕捉的精度,减小阻力预报的误差。

In order to solve the problem of unreasonable water distribution at planing hulls in numeri- cal simulation, VOF interface interpolation scheme and mesh types are studied and several measures are proposed to improve the capabilities of FLUENT, CFX and STAR-CCM＋ in predicting the per- formance of planing hulls. With the same hexahedral mesh and simulation setting, geo-reconstruct gives the best prediction in resistance and water distribution at planing hull, while HRIC gives the worst prediction. Suitable mesh type and mesh density could also improve the performance prediction. To improve the prediction accuracy, tetrahedral mesh should be used in CFX and polyhedral mesh should be used in STAR-CCM＋. It＇s advisable that suitable mesh type and mesh density or geo- reconstruct scheme should be adopted to improve the capabilities of CFD codes in predicting the per- formance of planing hulls.