声表面波飞机结冰传感器灵敏度及实验研究

Study of SAW Aircraft Ice Detector Sensitivity

声表面波飞机结冰传感器有望用于飞机结冰预测,其通过Love波的激发和在导波层中的传播变化,来敏感导波层表面冰的厚度及状态变化,而导波层的厚度对声表面波结冰传感器灵敏度具有重要影响。在学者Zimmermann的理论基础上,根据声表面波结冰传感器实际结构,计算得到导波层厚度对灵敏度影响的特性。通过对SiO2导波层及ST90°石英晶体压电材料进行实例计算,得其厚度在9.6μm处灵敏度最高,并通过实验对0.0042 m厚的冰层进行实验,得到冰层中Love波的传播速度,与理论计算吻合。

Surface acoustic wave ice detector is potential to he applied to aircraft icing forecast. Love wave is excited in substrate and propagate in guiding layer. Changes of Love wave could be used to sense the changing of ice thickness and the changing of ice physic state. In that case,the thickness of guiding layer makes great impact on the sensitivity of ice detector. Based on Zimmermann theory, the impact of guiding layer thickness on sensitivity was studied,according to the practical structure of ice detector. The sensitivity of ice detector, which used SiO2 as guiding layer and ST90° quartz as substrate,was computed. Result showed that the sensitivity was the highest when guiding layer thickness was 9. 6 μm. Experimental study was carried out to measure the Love wave phase velocity in 0. 004 2 m ice layer. The results showed that the experimental results was accorded with the theory＇calculation.