基于螺旋桨抽吸效应的潜艇水润滑尾轴承进水流量计算方法研究

Calculation method of water flow of water-lubricated stern bearing based on submarine propeller suction effect

舰艇水润滑后尾轴承依靠螺旋桨抽吸作用吸水进行润滑,但现有的水润滑轴承进水流量计算式未反映低速弱抽吸效应,无法满足尾轴承低速性能设计和试验要求。为此,本文基于计算流体力学软件STAR-CCM+,建立螺旋桨-潜艇尾尖舱-后尾轴承系统模型,提出同时兼顾螺旋桨流动和轴承间隙流动的多尺度流场仿真计算方法,研究螺旋桨抽吸作用机制和后尾轴承间隙流量的关键影响因素,拟合得到水润滑后尾轴承进水流量计算式。研究结果表明:对于结构确定的后尾轴承,影响间隙流量的主要因素是航速,其次是桨毂前端面与艇尾后端面距离,而尾舱门与舱壁间间隙以及是否含毂帽鳍对轴承流量影响非常小,可以忽略。所提出的进水流量计算式包括了轴直径、间隙和转速等变量,可为全转速范围内后尾轴承性能设计和试验考核时流量选择提供参考。

The water-lubricated rear stern bearing of the naval ship relies on the propeller suction effect by absorbing water for lubrication,but the existing water-lubricated bearing inlet flow calculation formula does not show the low-speed weak suction effect and cannot meet the low-speed performance design and test requirements of the stern bearing.So,a propeller-submarine afterpeak-stern bearing system model was established based on the computational fluid dynamics software STAR-CCM+.A multi-scale flow simulation method that took into account both propeller flow and rear stern bearing clearance flow was proposed.The key influencing factors of the propeller suction effect and the clearance flow of the rear stern bearing were studied,and the formula of water flow of water-lubricated rear stern bearing was obtained.The results of the study indicate that for the rear stern bearing with a defined structure,the main factor affecting the clearance flow is the speed.The distance between the front end surface of propeller hub and the rear end surface of the submarine has little effect on the bearing flow,while the gap between the stern door and the bulkhead,and whether the propeller boss cap fins are equipped have almost no effect on the bearing flow and can be ignored.The proposed calculation formula of inlet water flow includes variables such as shaft diameter,clearance and rotation speed,which can provide a reference for the design of the rear stern bearing performance in the full speed range and the flow selection during the test.