分布式拉杆转子轴向预紧力的确定

Determination of the Axial Pretightening Force of a Distributed Type Tie-rod Rotor

研究了分布式拉杆转子在考虑轮盘间接触效应时轴向预紧力的确定方法。分析了拉杆转子在不同工况下的转子最大等效应力,轮盘结合面最大、最小法向接触应力及转子弯曲刚度随拉杆预紧量变化的规律。结果表明:随着转子轴向预紧力的增加,转子能够传递更大的载荷,其弯曲刚度、固有频率与连续体的偏差更小,但转子的最大等效应力显著增加,材料的强度裕度显著降低。根据得到的拉杆转子最大等效应力结果、接触面法向应力分布、转子弯曲刚度结果及转子自由模态频率结果,确定了转子合适的轴向预紧力。当转子承受100 k N的切向载荷时,转子合适的预紧量范围为拉杆总长的7/10000—13/10000。

Studied was the method for determining the axial pretightening force of a distributed type tie-rod rotor when the contact effect between the wheel disks being taken into account and analyzed was the variation law governing the maximal equivalent stress of the rotor,maximal and minimal normal contact stress on the joint surfaces of the wheel disks and the bending rigidity of the rotor under various operating conditions with the pretightening amount of the tie-rod.It has been found that with an increase of the axial pretightening force of the rotor,the rotor can transfer a growing load and the deviation between its bending rigidity and intrinsic frequency and those of its continuum will become smaller,however,the maximal equivalent stress of the rotor will remarkably increase and the strength allowance of the material will markedly decrease. On the basis of the maximal equivalent stress of the tie-rod rotor,normal stress distribution on the contact surface,the bending rigidity and the free mode frequency of the rotor obtained,a proper axial pretightening force of the rotor was determined. When the rotor sustains a shear load of 100 KN,the proper pretightening force range of the rotor will be 7 /10000 to 13 /10000 of the total length of the tie-rod rotor.