带膜盘联轴节的动力传动轴的动力特性

带膜盘联轴节的动力传动轴是连接发动机和直升机传动系统的重要零件,其动力特性与一般结构形式的轴有所不同.文中采用有限元计算分析与试验验证相结合的方法,研究这种结构的动力传动轴的刚度、固有频率和转子动力特性.结果表明,这种动力传动轴的1阶振型通常表现为膜盘变形振动,轴的刚度和1阶固有频率随膜盘厚度的增大而增大,而1阶临界转速却基本不随膜盘厚度的变化而变.     

航空发动机动力涡轮单元体高速动平衡试验研究

针对涡轴发动机动力涡轮转子在高速动平衡后必须经过分解和重新装配才能装在发动机中使用而带来的不足,提出直接对动力涡轮单元体进行高速动平衡试验.完成单元体的动力特性计算,通过分析单元体在发动机中的安装情况,设计并实施单元体的平衡方案,在此基础上完成动力涡轮单元体的高速动平衡试验,效果良好,平衡后的单元体没有经过分解和重新装配直接装机使用,并在发动机整机台架试车中表现出良好的振动特性,单元体的高速动平衡完全有希望取代动力涡轮转子的高速动平衡,而发展成为一项生产平衡技术,有很高的工程应用价值.     

不平衡量对非线性转子-挤压油膜阻尼器系统临界转速影响的研究

对动力涡轮转子这种柔性细长轴超临界转子进行动平衡时,需要知道知道转子运行的模态信息以及动平衡影响系数。基于ANSYS有限元分析软件建立了动力涡轮转子-挤压油膜阻尼器的动力学模型,提出了一种考虑阻尼器偏心率和转速变化的变刚度阻尼系数不平衡谐响应计算方法。通过计算发现:由于挤压油膜阻尼器的非线性特性,会导致转子系统的临界转速随着不平衡量的增加而明显增加。同时,这也导致了同一位置、同一转速下,动平衡影响系数也会随着不平衡量的变化而变化。在进行这类转子动平衡时,需高度重视这2种现象。     

裂纹转子不平衡响应的有限元分析

首先由应力强度因子积分得到含裂纹轴段单元体的刚度矩阵，继而建立了含裂纹转子系统的运动微分方程。通过数值计算得到含裂纹转子系统的振动特性随裂纹的开闭、随裂纹的位置及深度间的变化关系。选定对裂纹比较敏感、又能反映结构动力特性的不平衡响应轨道（轴心轨迹）作为诊断裂纹的依据，编制了不平衡响应计算和动力分析程序。仿真试验结果表明，本文的裂纹诊断的有限元分析方法是可行的，具有较高的精度。     

基于有限元的传动轴受扭分析

以有限元软件ANSYS为基础,论述了传动轴的初步设计,校核了其强度、刚度.对空心传动轴和实心传动轴的结果进行了分析比较并得出结论.与传统算法相比,该方法可以准确的描述传动轴的应力和应变的大小和位置,便于进行精确的轴强度计算.     

基于ANSYS的汽车传动轴的有限元分析

利用ANSYS进行传动轴的强度及刚度校核,给出相应的扭转应力、单位扭转角等数据有限元分析结果,在进行强度及刚度校核时,还将利用ANSYS进行验证。在相同的受力条件下,分别对实心轴和空心轴进行应力分析,分析出传动轴中空心轴和实心轴的性能优劣,为传动轴设计提供理论依据。对实际工程中选用有着重要参考意义。     

汽车起重机传动轴可靠性设计

汽车起重机传动轴可靠性设计南京工程兵工程学院陈海松，严骏，熊云在汽车起重机中，传动轴常用于变速箱与驱动桥之间的连接。这种轴一般较长，且转速高。为使传动轴具有足够的刚度和高临界转速，现在传动轴均采用空心轴。空心传动轴的传统设计方法是以材料力学为基础，根...     

海军某大功率舰用燃气轮机性能试验阶段的故障诊断

本文介绍了某舰改燃气轮机在其性能实验阶段有关故障诊断工作的概况。给出了在试验过程中准确诊断和排除该机的动力涡轮转子失衡，膜片联轴节传动轴结构不稳定，起动机脱落和整机结构三重点自激响应等诸多故障的实例。     

基于有限元法的直升机动力传动轴的设计

针对某型直升机传动系统的动力传动轴的两种设计构型,计算了动力传动轴两种构型的静强度和临界转速,得到构型Ⅱ动力传动轴是最优设计的结论。动力传动轴的静强度和临界转速计算方法为同类产品的研制提供了参考和依据。     

某动力涡轮转子连接圆弧端齿的优化设计

针对圆弧端齿开设螺栓孔会破坏圆弧端齿齿形结构的完整性、产生局部应力集中等问题，建立了带有螺栓预紧的动力涡轮盘轴圆弧端齿连接转子优化模型，基于ANSYS优化平台进行了带螺栓孔的圆弧端齿结构优化设计。分析结果表明，螺栓孔的开设对圆弧端齿齿底的强度削弱作用要比对凹（凸）齿本身的大，且将螺栓孔径向分布在圆弧端齿的节圆直径附近有利于降低圆弧端齿结构的应力和改善应力分布；在满足其他应力约束条件下，优化后的圆弧端齿最大等效应力比原始方案降低9.1%，端齿工作面最大接触应力降低44.6%，改善了圆弧端齿齿根附近的应力分布状态，同时也没有对动力涡轮盘轴转子变形产生影响。     

半主动TMD控制双跨轴系过临界振动的研究

针对多轴串联机械通过临界转速时振动过大的问题,对调谐质量阻尼器在双跨轴系振动控制中的应用进行了研究。并基于转子结构,设计了具有对称结构的笼式半主动调谐质量阻尼器用于控制轴系振动;搭建了双跨转子实验台,在不改变转子轴系原有支撑形式上,在两根轴上分别安装了调谐质量阻尼器,对调谐质量阻尼器对轴系各跨转子振动的影响规律进行了实验研究。研究结果表明,不可控调谐质量阻尼器可以有效抑制安装所在轴临界转速附近的振动,对相邻轴影响较小,但会引起新共振峰。根据此实验结果通过开关控制策略实现调谐质量阻尼器半主动控制,说明半主动调谐质量阻尼器可以在不停机的情况下,抑制转子轴系通过各阶临界转速时的振动,避免失谐。     

转子系统动力特性分析

用传递矩阵法推导转子系统临界转速和动态不平衡响应的计算公式 ,用 MATL AB软件编写了相应的计算程序 ,用一个有理论解的例子对程序进行考核。对一模型悬臂转子进行了比较全面的分析 ,得出了转子系统的临界转速的变化规律。在此基础上对某实际火箭发动机转子系统的动力学特性进行了分析。研究了联轴器刚度、浮动环刚度等对转子特性的影响     

Fluid-structure interaction analysis of annular seals and rotor systems in multi-stage pumps

Annular seals play an important role in determining the vibrational behavior of rotors in multi-stage pumps. To determine the critical speeds and unbalanced responses of rotor systems which consider annular seals, a fluid-structure interaction (FSI) method was developed, and the numerical method was verified by experiments conducted on a model rotor. In a typical FSI process, rotor systems are modeled based on a node-element method, and the motion equations are expressed in a type of matrix. To consider the influence of annular seals, dynamic coefficients of annular seals were introduced into the motion equations through matrix transformation. The test results of the model rotor showed good agreement with the calculated results. Based on the FSI method proposed here, the governing equations of annular seals were solved in two different ways. The results showed that the Childs method is more accurate in predicting a rotor’s critical speed. The critical speeds of the model rotor were calculated at different clearance sizes and length/diameter ratios. Tilting coefficients of long seals were added to the dynamic coefficients to consider the influence of tilting. The critical speeds reached their maximum value when the L/D ratio was around 1.25, and tilting enhanced the rotor’s stability when long annular seals were located in either end of the shaft.     

Evaluation of the influence of the initial deflection curve shape of a two-span rotor with residual imbalance on its vibroactivity during rundown

This work is devoted to the evaluation of the influence of the curve shape of the ineradicable initial deflection of a two-span rotor with the residual imbalance on the transition vibration amplitudes at low critical speeds under the rundown. The model corresponds to a high-pressure rotor–combined mid-low-pressure rotor (HPR–MLPR) system of a turbine unit. It is assumed that rotors are connected by a rigid coupling and installed on anisotropic elastic damper supports. It is supposed that the resulting deflection (bend) of this system is formed as a result of the fact that a high-pressure rotor acquires the initial deflection during the operation or because of abnormal launch conditions, the curve shape of which for a load-free rotor is known. The influence of the mutual arrangement of the residual imbalances of rotors and the imbalances caused by the resulting deflection of shafting in a system on the amplitudes of its transition vibration under the rundown of a turbine unit has been studied for two shapes of the initial rotor deflection curve that have the highest and lowest values of the shape parameter. The values of the initial rotor bending deflection and the residual imbalance of both rotors have been set equal to the maximum acceptable values for the operation of a turbine unit. Amplitude calculations have been performed for rotors of a K-300-23.5 Leningrad Mechanical plant (LMZ) turbine.     

风力机与液力变速传动装置匹配工作特性研究

通过对液力变速传动装置应用于风力发电系统运动规律的分析,得到了适应变化的风轮转速、保持恒定发电机输入转速的风轮转速与液力变矩器涡轮输出转速应保持的关系。根据传动系的功率分流原理及能量平衡方程,推导了液力变矩器泵轮输入功率占风轮功率的比例以及液力变速传动装置的总体传动效率关系式。结合风力机特性进行了液力变矩器涡轮输出工作特性的分析,综合评价了影响传动效率的主要因素。针对低转速比和高转速比两种型号的液力变矩器进行了系统的匹配计算,为液力元件的选型与设计、差动轮系及定轴轮系关键结构参数的选取提供了参考。
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Stability of Rotors Under the Combined Influence of Fluid Film Bearing Characteristics and Shaft Material Damping

Fluid film characteristics and shaft material damping form an interesting combination in rotor dynamic applications. Under certain conditions, a rotor which is unstable due to the damping, can be stabilized with the proper choice of fluid film bearings as supports. On the other hand, increasing the material damping in the rotor shaft can attenuate stress fluctuations in the rotors supported by fluid film bearings. The influence of the above combination on the stability of rotor bearing systems is investigated using a Jeff cot rotor with significant material damping and supported by fluid film bearings in the rotor dynamic model. The results indicate that under certain conditions, the interaction of the above two factors can be gainfully utilized in the design of rotor bearing systems.     

储能飞轮过盈/脱落过程研究

核电冷却剂泵上安装飞轮,用以储备转动惯量,保证在泵电动机断电时冷却剂流量缓慢下降,避免反应堆事故。采取过盈配合的目的是控制飞轮临界转速。过速情况下,飞轮发生膨胀,从立轴脱落,可以预防爆裂的发生。设计了一套由临界转速控制的逐层脱落的安全飞轮。运用平面应力法与包含间隙元的有限元模型,对飞轮进行过盈设计和应力分析。在递增的离心力作用下,对飞轮摩擦配合的连续、滑动、脱落过程进行完整仿真。     

350t转子超速动平衡试验站装备的设计制造

350 t转子超速动平衡试验站用于大型汽轮机发电设备和大型核能发电设备上转子的超速动平衡试验。本文对上海电气350 t转子超速动平衡试验站在建设过程中的设计、制造、安装、调试环节进行了介绍。     

Bearing influenced rotor dynamics

This paper presents a brief summary of the influence of journal bearings in machinery with special reference to rotor dynamic problems. The journal bearings considered are Newtonian, non-Newtonina and magnetohydrodynamic and their influence on the critical speeds and stability of rotors is investigated