摘要
以全附体SUBOFF潜艇桨盘面处标称伴流作为七叶大侧斜桨的非均匀进流,分析了对空化引起的推力和力矩崩溃性能以及叶背梢涡空化初生的影响,描述了非均匀进流条件下空化时推力和力矩的脉动特征、桨叶空化面积和空化形态随周向位置的变化,并给出了伴流中螺旋桨是否出现叶面片空化的区间划分。空化模拟时采用改进Sauer空化模型和修正SST湍流模型。梢涡空化初生依据作者提出的"当σ>σi时,叶截面压力系数分布不再改变"的相对准则来判定。结果表明,伴流能够有效延迟该桨叶面片空化初生,但同时会使叶背片空化初生提前且空化范围明显增加;在对应敞水效率最高的工况点,伴流使得该桨因空化引起的推力下降起始点较均匀来流时提前量大于7.1%,且叶背梢涡空化初生提前量大于6.7%;即使在空化较为严重的情况下,该桨在伴流场中的推力和力矩脉动幅值也很小;由于桨叶旋向的影响,一周内桨叶空化面积对于艇尾左右舷空间并不完全对称。研究结果可用于分析大侧斜使艇尾桨空化初始航速提高一定程度的现象。
The effects of submarine nominal wake on 7-bladed highly-skewed propeller＇s thrust and torque cavitation breakdown performances and the suction side tip vortex cavitation inception were numerical investigated at first. Then the thrust and torque fluctuations under cavitatiofi condition With the non-uniform inflow were presented, and the blades cavity area andcavity pattern in one week, and the circumferential region inducing the face sheet cavitation were analyzed. The improved Saner cavitation model and the modified shear stress transport turbulence model were adopted in the cavitation simulation. And the rule proposed by the author ＂when σ〉 σ1, the pressure coefficient of the blade section is unchangeable＂ was used again to determine the tip vortex cavitation inception. The results show that the wake can significantly delay the face sheet cavitation inception of the propeller, but will quicken the back .sheet cavitation inception and enlarge the cavity extension, and make the cavitation breakdown performances worsen also. Exactly speaking, as for the J=0.6 condition corresponding to the highest open water efficiency point, the wake makes the beginning point of thrust decline due to cavitation shift earlier than 7.1% comparing to the uniform inflow, and the back tip vortex cavitation inception ahead more than 6.7% at the same time. Even under the relatively severe cavitation condition, the fluctuated amplitude of the thrust and torque is quite small. Due to the rotating direction effect, the cavity area in one circle is non-symmetrical as to the port and starboard. The results above can be used to answer the problem of why can the high skew be beneficial to elevate the cavitation inception ship to some extent.
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
2011年第5期538-550,共13页
Chinese Journal of Hydrodynamics
基金
国家自然科学基金项目(51009144)
关键词
螺旋桨
非均匀进流
空化初生
推力崩溃
空化模型
Propeller
non-uniform inflow
cavitation inception
thrust breakdown
cavitation model
