联轴器不对中状态对船舶轴系动力学特性影响的试验

针对某船舶高速轴系不对中状态对轴系振动的影响,建立涡轮转子-传动轴-太阳轮转子试验模型,通过调整轴承支座的标高来模拟平行不对中和转角不对中量,进行多次升降速试验获得靠近轴承处的转子的振动位移。研究表明:不同的联轴器不对中状态对轴系的临界转速没有影响;在工作转速4 200 r/min时,不同联轴器对中状态下轴系各测点基频振动幅值变化很小,靠近套齿联轴器的太阳轮右侧轴承处转子2倍频振动明显大于左侧轴承处的振动;整体抬高太阳轮轴系标高对2倍频振动的影响较小;太阳轮左侧轴承支座标高降低时各轴承处2倍频振动幅值均有一定程度的增大;降低涡轮驱动端轴承支座的标高,轴系2倍频振动幅值整体增大;各对中状态下所有测点振动幅值的计算值与试验测量值的平均偏差小于20%,不同的对中状态对涡轮机转子的振动影响均小于对太阳轮转子的影响。

Experiment of the Influence of the Non alignment of a Coupling on the Dynamic Characteristics of a Shaft System in a Ship

Abstract:To study the influence of the non alignment on the vibration of a high speed shaft system in a ship,established was a turbine rotor-transmission shaft-sun wheel rotor test model.The elevations of the bearing pedestals were adjusted to simulate the non-alignment in parallel and rotating angles.Through the speed-up-and-down tests performed for several times,the vibration displacements of the rotor at places near to the bearings were obtained.It has been found that the non-alignment of various couplings will have no influence on the critical rotating speed of the shaft system.At a rotating speed of 4 200 r/min,the vibration amplitudes at various measuring points of the shaft system under different alignment states of the couplings at the base frequency will have a very small change and that of the rotor at the two fold frequency at the location of the bearing nearing the right side of the sun wheel of the geared coupling will be obviously bigger than that at the location of the bearing nearing the left side of the sun wheel.To heighten the elevation of the shaft system of the sun wheel as a whole will have a relatively small influence on the vibration amplitude at the two fold frequency.When the elevation of the bearing pedestal at the left side of the sun wheel goes down,the vibration amplitudes at locations of various bearings will all increase to a certain extent.To lower the elevation of the bearing pedestal at the driving end of the turbine will increase the vibration amplitudes of the shaft system as a whole at the two fold frequency.The average deviation between the vibration amplitudes calculated at all measuring points under different alignment states and those tested and measured will be less than 20%.The influence of various alignment states on the vibration amplitude of the turbine rotor will be all smaller than that on the rotor of the sun wheel.