定则振动系统下黄冠梨振动特性及损伤研究

目的通过对黄冠梨进行振动试验测试,研究其在定则振动系统下的振动特性以及振动加速度、振动频率与其他振动参数对黄冠梨损伤的影响,建立黄冠梨面积、体积损伤率与时间关系模型。方法通过定则振动中的扫频试验和定频试验,分析黄冠梨的振动加速度与共振频率、能量传递率之间的关系,研究黄冠梨面积损伤率和体积损伤率的变化规律。结果黄冠梨的共振频率随加速度的增大呈下降趋势,0.85g后共振频率基本无明显变化,7层黄冠梨从下至上各层共振频率变化趋势相似。随着振动加速度的增大,单层黄冠梨的共振频率与能量传递率均逐渐变小。结论单层黄冠梨的加速度与共振频率呈非线性关系,多层黄冠梨的面积损伤率与体积损伤率随着层数的增加而变大,其共振频率随着层数的增加而减小。

Vibration Characteristic and Injury of Huangguan Pearunder Stationary Vibration System

The work aims to study the influence of vibration characteristics, vibration acceleration, vibration frequency and othervibration parameters on the injury of Huangguan pear under the stationary vibration system, and establish the model for the relationship between the injury rates of Huangguan pear area and volume and the time, through its vibration test. Based on the sweep scanning and fixed frequency testsin the stationary vibration, the relationship between Huangguan pear vibration acceleration, resonance frequency andenergy transfer rate was analyzed. The change law of injury rates of Huangguan pear area and volume was studied. The resonance frequency of Huanggu pear decreased with the increase in the acceleration, and itbasically had no obvious change after 0.85g. The change trend of resonance frequency of Huanggu pear from the bottom up was similar in each layer (7 layers in total). With the increase in the vibration acceleration, both the resonance frequency and the energy transfer rate of Huangguan pear in a single layer become smaller. The acceleration and the resonance frequency of Huangguan pear in a single layer is in a nonlinear relationship. The injury rates of Huangguan pear area and volume in multiple layers become bigger with the increase in the layer number. The resonance frequency decreases with the increase in the layer number.