车下弹性吊挂设备悬挂刚度选取方法
Suspension stiffness selecting method of elastic suspension equipment under vehicle

以车体低阶弹性振动、刚体振动和设备有源振动为输入,提出了一种能够快速、简便确定弹性设备悬挂刚度的方法; 在充分考虑吊挂设备各个方向上可能出现耦合振动、设备安装间隙、允许最大振动位移等因素的前提下,推导了任意悬挂方式吊挂设备的刚体振动频率计算公式; 给出了车下弹性吊挂设备悬挂刚度的选取方法与分析流程; 以某动车组为例,建立了车体与动力包的耦合振动分析模型,计算得到了动力包的点头、摇头、浮沉、侧滚等刚体振动频率和三向悬挂刚度的取值范围,并对比了动力包悬挂刚度理论计算结果与有限元结果。研究结果表明:在已知车体或吊挂设备基本参数的前提下,采用提出的方法无需通过复杂的动力学建模分析即可计算出其点头、摇头、浮沉、侧滚等刚体振动频率,与有限元计算结果相比,刚体振动频率的最大相对误差为6.88%; 计算所得动力包刚体振动频率与车体对应振动频率的比值均有效避开了耦合区间[0.750,1.414],因此,采用提出的方法可快速、准确地确定吊挂设备的刚度范围,从而避免设备与车体之间的共振。
Taking the low-order elastic vibration, the rigid body vibration and the equipment active vibration of carbody as inputs, a method for rapidly and simply determining the suspension stiffness of elastic equipment was proposed. Under the premise of fully considering the coupling vibration that may occur in all directions, equipment installation clearance, the maximum allowable vibration displacement of suspension equipment and other factors, the formula for calculating the rigid body vibration frequency of suspended equipment with arbitrary suspension method was derived. The selection method and analysis process of suspension stiffness of elastic suspension equipment under vehicle were given. Taking a certain electric multiple unit(EMU)as an example, the coupled vibration analysis model of carbody and power pack was established. The ranges of rigid body vibration frequencies of nodding, shaking, floating and sinking, lateral rolling, and three-dimensional suspension stiffnesses of power pack were calculated, and the theoretical calculation results of suspension stiffness of power pack were compared with corresponding finite element results. Research result shows that under the premise that the basic parameters of carbody or suspension equipment are known, the proposed method can calculate the rigid body vibration frequencies of nodding, shaking, floating and sinking, and lateral rolling, without complicated dynamic modeling and analysis. Comparing with the finite element calculation result, the maximum relative error in rigid body vibration frequency is 6.88%. All the calculated frequency ratios between rigid body vibration frequencies of power pack and corresponding vibration frequencies of carbody can effectively avoid the coupling interval [0.750,1.414]. Therefore, the stiffness of elastic suspension equipment under vehicle calculated by the proposed method can quickly and accurately determine the stiffness rang of suspension equipment, so as to avoid the resonance between equipment and carbody. 9 tabs, 8 figs, 30 refs