针对超声波测量螺栓应力中涂敷耦合剂厚度不容易测量的问题,采用有限元COMSOL Multi physics仿真软件,通过对比超声波信号穿过凡士林、机油和环氧树脂后的声压强强度,进而比较出信号衰减情况.仿真结果表明:通过观察回波信号的峰值大小,环氧树脂的耦合效果是最好的,能使超声波脉冲信号的衰减降到最低,而环氧树脂由于其较高的硬度和刚性,通常具有较低的吸收和散射能力,因此对超声波的透射率和声速的影响较小.凡士林其次,机油最差.耦合剂的厚度是越薄越好,越薄的耦合剂,超声波能量衰减越少.材料的厚度增加会导致超声波的透射率降低,这是因为较厚的材料能够吸收、散射和反射更多的超声波能量,使得透射的能量相对减少.
Simulation Study on Influence of Coupling Agents in Bolt Stress Measurement
In response to the difficulty in measuring the thickness of coupling agent applied in ultrasonic stress meas-urement of bolts,the finite element software COMSOL Multi physics simulation software was used to compare the sound pressure intensity of ultrasonic signals passing through Vaseline,engine oil,and epoxy resin,and then compare the signal attenuation situation.The simulation results show that by observing the peak value of the echo signal,the coupling effect of epoxy resin is the best,which can minimize the attenuation of ultrasonic pulse signals.However,epoxy resin,due to its high hardness and rigidity,usually has lower absorption and scattering abilities,so its impact on the transmittance and ve-locity of ultrasonic waves is relatively small.Vaseline ranks second,while engine oil is the worst.The thinner the cou-pling agent,the better.A thinner coupling agent results in less attenuation of ultrasonic energy.An increase in material thickness can lead to a decrease in the transmittance of ultrasonic waves,as thicker materials can absorb,scatter,and re-flect more ultrasonic energy,resulting in a relative reduction in transmitted energy.
Ultrasonic non-destructive testingMeasurement of bolt stressCoupling agentCOMSOL simulation
万方数据
维普
