船舶单桨工况拖转调距桨性能计算及其对快速性的影响分析

Simulation on the steady-state and dynamic characteristics of single propeller working condition of ship propulsion system

利用CFD方法对某调距桨敞水特性进行数值计算,并利用实验数据对计算结果进行校验。对于该桨各螺距下大进速系数时的敞水性能采用CFD计算结果与二次曲线逼近相结合的方法获得,以适当扩大调距桨的敞水特性曲线在水涡轮工况的范围。建立了某推进装置主机、传动装置、调距桨、船体阻力的数学模型,在Simulink环境下集成为"船-桨-机"推进系统仿真模型。对单桨工况的稳态特性进行仿真计算,着重研究了不工作调距桨自由拖桨时的拖桨阻力。结果表明:1)不工作桨自由拖转时,将不工作桨螺距设定为最大值时拖桨阻力最小,船舶的快速性最好;2)航速和不工作桨螺距是影响不工作桨拖桨阻力的主要因素,航速越高,拖桨阻力、拖桨力矩以及拖桨转速越大;不工作桨螺距越大,拖桨阻力越小,拖桨力矩与拖桨转速先略微增加而后减小至最小值。

The open water performance of controllable pitch propeller（CPP） is numerically simulated by CFD method,and the result is verified by the test data. When the advance ratio is big the open water performance is attained by both CFD method and conic approach arithmetic, which extending the range of the open water performance curve. The mathematic models of main engine, transmission system, controllable pitch propeller and hull resistance are developed, and the ＂hull-propeller-engine＂ propulsion system simulation model is integrated in Simulink. The steady-state characteristics of single propeller working condition is simulated, in which the resistance of the unworking propeller is studied chiefly, the simulation results show that： When the unworking propeller is free running, the resistance added by the unworking propeller is the smallest and the speed-ability is the best when the pitch of this propeller is at the maximal position. The ship speed and the pitch of the unworking propeller are the two major factors which influence the performances of the unworking propeller. With the increasing of ship speed, the added dragged resistance, torque and rev of the unworking propeller increase too, and the increasing of the pitch of the unworking propeller will cause the reduced free running propeller＇s dragged resistance, the torque and rev increase appreciably at first and then decrease to the minimum value.