摘要
同时采用Lerbs非最优螺旋桨理论和Epps最佳环量分布理论,将螺旋桨升力线方法由初始设计应用扩展到敝水性能预报,对DTMB 4119、4381、4382和4497这4个螺旋桨的敞水性能曲线进行了预报分析.针对升力线方法在中度负载区间的适用限制和无法在黏性流场中考虑桨叶空化性能的缺陷,进一步将Epps方法与雷诺时均(RANS)模拟相结合,可明显提高低、高负载区间的敞水性能预报精度.Epps方法预报精度要高于Lerbs方法,能够满足工程初始分析需求.随着远离设计工况点(低、高进速系数)其预报误差变大,桨叶侧斜程度和纵倾存在也会增大预报误差.RANS模拟时桨叶切面型值由升力线方法提供,桨叶几何和六面体网格划分均采用程式化操作实现.在分析网格因素影响后,所得推力和力矩系数以及压力系数分布均匀与实验值吻合较好.在RANS模拟中加入混合物均相流空化模型后,可定量得出桨叶梢涡涡束在一定距离内的螺旋轨迹.结合桨叶最大负载截面的空化斗性能和梢涡涡束最小压力点幅值,可相对判定桨叶空化性能.构建了基于水动力性能评价的螺旋桨参数化设计和非空化与空化性能预报的数值平台.
Both of the Lerbs non-optimum propellers theory and Epps optimum circulation distribution theory were adopted to enlarge the propeller traditional lifting-line preliminary design to open water performance curves prediction. All of the DTMB 4119, 4381, 4382, 4497 propellers＇ off-design performances were analyzed by this method. The precision of the Epp method is higher than that of Lerhs, and is fit for engineering preliminary analysis. With furthering away from the design point （low and high advance coefficients）, the prediction difference gets larger, and the skew angle amplitude and the rake exist will also increase the prediction error. To overcome the moderately loaded limit and analyze blade cavitation performance comprehensively within the viscous field, the lifting-line theory and RANS simulation were integratedto enhance off-design hydrodynamic characteristics prediction. The blade section offsets input to RANS calculation were obtained from lifting-line method. Blade geometry modeling and hex meshes were both completed by procedure control. After analysis of mesh sensitive effects on RANS simulation, the calculated thrust and torque coefficient and pressure coefficient distribution are all fit well with the experiment. After the mixture homogeneous cavitation model is adopted into the RANS simulation, the results quantitatively present the blade tip vortex filament＇s helical track within a little distance, in which the smallest pressure magnitude can be combined with the cavitation bucket performance of the biggest load section to relatively determine the propeller＇s cavitation performance. The numerical system for propeller parametric design and non-cavitation and cavitation hydrodynamic performances prediction based on hydrodynamics was constructed.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2011年第4期486-493,共8页
Journal of Shanghai Jiaotong University
基金
国家自然科学基金资助项目(51009144)
关键词
船舶
螺旋桨
升力线理论
雷诺时均模拟
螺旋桨设计
敞水性能
空化性能
ship
propeller
lifting line theory
reynolds averaged navier-stokes（RANS） simulation
propeller design
open water performances
cavitation performance
