【作者】 李飞；

【导师】 柏林；

【作者基本信息】 重庆大学 ， 工程（机械工程）（专业学位）， 2022， 硕士

【摘要】 由于复合材料转轴具有比强度高、比刚度高、密度低、热膨胀系数小和减振性能好等优点,其在直升机、汽车和轮船等设备的传动系统中得到了广泛应用。在复合材料转轴的设计制造中,不平衡量的大小是必须要考虑的重要因素。复合材料转轴具有各向异性、挠性和高速等特点,其在一阶临界转速下挠度很大且振动剧烈,导致复合材料转轴的动平衡难度很大。常用的动平衡方法如影响系数法等,在实际应用中对复合材料转轴的平衡效果不够理想,因此针对复合材料转轴的动平衡问题需要进一步进行研究。本文结合某复合材料转轴实际项目需求,通过研究复合材料转轴动平衡特点,提出了针对复合材料转轴进行平衡的全频正交融合动平衡法,并最终开发出一套复合材料转轴的动平衡测试系统。本文的主要工作包括:(1)针对复合材料转轴动平衡特点,提出了一种全频正交融合动平衡法,这种方法将全频谱与力和力偶分解平衡法相结合对转轴进行平衡。该方法首先采集转轴两端水平、垂直方向上的加速度信号,提取出信号基频的幅值和相位,然后利用全频谱同源信息融合技术,将水平、垂直方向上振动响应融合成正进动矢量,将正进动矢量作为不平衡响应代入力和力偶分解平衡法,以此求解转轴不平衡量。(2)建立复合材料转轴动力学模型,对复合材料转轴的临界转速、模态振型和谐波响应等动力学特性进行了分析。利用复合材料转轴模型进行模拟动平衡,结果表明,全频正交融合动平衡法对复合材料转轴的平衡效果较好。针对复合材料转轴动平衡效果受平衡面的位置影响较大的问题,分析了动平衡过程中平衡面的选取原则。仿真分析和实验的结果表明,对复合材料转轴的临界状态进行平衡时,平衡面取在转轴中部附近较好,对转轴的工作状态进行平衡时,平衡面选取在轴端的附近较好。(3)针对实际项目需求开发一套动平衡测试系统。首先对测试系统的需求进行分析,根据需求完成对硬件的选型与安装。然后利用Lab VIEW开发平台对软件部分进行开发,介绍了软件的整体架构,并对软件的一些主要功能模块进行了设计。现场复合材料转轴动平衡实例表明,该动平衡测试系统可以完成对复合材料转轴的平衡,并使其达到平衡指标。更多还原

【Abstract】 Due to the advantages of high specific strength,high specific stiffness,low density,low thermal expansion coefficient and good vibration damping performance,composite shafts have been widely used in the transmission systems of helicopters,automobiles,ships and other equipment.In the design and manufacture of composite shafts,the size of the unbalance is an important factor that must be considered.Composite shafts have the characteristics of anisotropy,flexibility and high speed,and their deflection and vibration are great at the first critical speed.These characteristics make the dynamic balance of composite shafts very difficult.The commonly used dynamic balance methods,such as the influence coefficient method,have poor balance effect on the composite shaft in the actual measurement.Therefore,the dynamic balance of the composite shaft needs to be further studied.Combined with the actual project requirements of a composite shaft,this paper proposes a full spectrum quadrature fusion dynamic balance method that can balance the composite shaft by studying the dynamic balance characteristics of the composite shaft.This article mainly includes the following contents.(1)According to the dynamic balancing characteristics of composite shaft,a full spectrum quadrature fusion dynamic balance method is proposed.The principle of this method is to use the full spectrum same source information fusion technology to fuse the vibration responses in the horizontal and vertical directions into a forward response,and substitute the forward response as an unbalanced response into the force and couple decomposition balance method to solve the shaft unbalance.(2)The critical speed,modal shape and harmonic response of the composite shaft are analyzed by establishing the dynamic model of the composite shaft.Using the composite shaft model to simulate the dynamic balance,it is proved that the full spectrum quadrature fusion dynamic balance method has a good balance effect on the composite shaft.Aiming at the problem that the dynamic balancing effect of composite shaft is greatly affected by the position of balance plane,the selection principle of balance plane in dynamic balancing process is analyzed.The results show that when balancing the critical state of composite shaft,it is better to choose the balance plane near the middle of the shaft,and when balancing the working state of the shaft,it is better to choose the balance plane near the shaft end.This result is verified by comparative experiment.(3)To develop a dynamic balance test system according to actual project requirements.Firstly,the requirements of the test system are analyzed,and the hardware selection and installation are completed according to the requirements.Then use Lab VIEW development platform to complete the software part of the development,determine the overall architecture of the software,and some of the main functional modules of the software system are introduced.An example of dynamic balance of composite shaft is given to prove that the dynamic balance test system can balance composite shaft and make it reach the balance index.更多还原