导　　师： 吴伟亮

学科专业： 0807

授予学位： 硕士

作　　者： ;

机构地区： 上海交通大学

摘　　要： 在船舶实际工作过程中，轴系的振动特性对轴系设计、安装以及船舶整体振动都有重要的影响，而通过轴系校中计算能够保障主机及轴系的安全运行，同时减小船体振动，所以，振动、校中计算的重要性不言而喻。本文根据某气垫船的实际结构特性，建立有限元模型，计算其回转振动、纵向振动、扭转振动，并进行直线校中及合理校中计算，最后在ANSYS的基础上进行软件的二次开发。 本文在回转振动计算时，在不考虑船体刚度及考虑船体刚度两种情况下，得到了垫升轴系的一次共振转速范围及叶片次共振转速范围，虽然考虑船体刚度时整体刚度会下降，轴系的回转振动仍然处于安全运转范围内；通过计算验证了陀螺效应对回转振动的影响；确定了垫升轴系纵向振动及扭转振动时的固有频率及振型，并讨论了轴承刚度对纵向振动及扭转振动的影响，同时分析了强迫振动中干扰力及干扰力矩的来源，给出了在外界干扰力及干扰力矩的作用下轴系的响应情况，分析了阻尼大小对轴系振动响应的影响。气垫船垫升轴系校中计算分为两块，在直线校中计算中分刚性支承和弹性支承两方面进行计算分析，计算结果显示弹性支承与刚性支承相比，轴承上的支反力减小，弯矩、剪力基本无变化，同时还计算了轴承负荷影响系数及弯矩影响系数，分析了在刚性支承和弹性支承下计算结果不同的原因；在合理校中计算中给出了具体的优化方案，展示了在ANSYS优化设计器OPT中的优化结果，结果显示轴承负荷得到了改善，在合理校中热态计算中确定了各轴承因温升而引起的最大升高量，为轴系的安全运转提供了参考。 最后，在Visual C++与ANSYS的参数化设计语言APDL相结合的基础上开发了船舶轴系振动及校中的专用软件，使得对于不熟悉有限元分析软� In the actual work of the vessel, shafting vibration characteristicshave a great impact on its design, installation and overall vibration. Thecalculation of shaft alignment can guarantee the safe operation of the mainengine and shafting, as well as reducing the hull vibration, which manifeststhe importance of the vibration and alignment’s calculation. In this paper, afinite element model was established according to the actual structuralcharacteristics of the shafting on the hovercraft for analyzing its lateralvibration, longitudinal vibration and torsional vibration, and then thecalculation in straight shaft alignment and in optimum alignment has beenconducted. Finally re-development of software was done based onANSYS. On the base of considering the hull stiffness, the region of resonancespeed and blade resonance speed of the shafting was calculated underdifferent bearing stiffness and compared with the condition of taking noconsideration of the hull stiffness. Although overall stiffness would bereduced considering the hull stiffness, it still can be concluded that thelateral vibration of the shafting is in safety in accordance with workingspeed. The gyroscopic effect on the lateral vibration of the shafting wastested through calculation. The natural frequencies and the correspondingmode shapes of the longitudinal vibration and torsional vibration weredetermined. Bearing Stiffness effect on shafting vibration frequency wasalso discussed. Furthermore, by analyzing the sources of the excitationforce and moment in forced vibration and presenting the shaft response to excitation, the influence of damping on shafting vibration response wasanalyzed. Calculation in alignment can be divided into two parts. Instraight shaft alignment, it showed that bearing reactions decreased, whileshear force and moment had no change taking consideration of bearingstiffness. Influence coefficient of load and moment were calculated in twodifferent conditions and the reason of the differences was also given. Inoptimum alignment, spe

关 键 词： 有限元 振动 轴系校中 二次开发

领　　域： [交通运输工程] [交通运输工程]