This work is an experimental research to investigate the gas fuel (CH₄) characteristics necessary for natural gas vehicles based on ultrasonic-assisted measurement using two different ultrasonic sensors. This paper offers the technical methods including energy transfer process, ultrasonic propagation, sensitivity, amplitude signal, and relationship of CH₄ density and ultrasonic signal. The experiment is composed of a constant volume chamber (CVC), two different sensors (AUS and HSUS), and gas fuel (methane). The experimental conditions are set by 1 ∼ 4 bar of initial pressure, 7 Hz of pulse rate, 53.7 kHz of resonant frequency, and 0.45 ∼ 0.85 m of measurement distance in natural gas space. As a result, HSUS is measured by 0.92 V of the height, 4 cm of main width, 12.7 cm of full width, and 42.8° of slope angle. The important thing is to highly increase the height and slope angle of HSUS model comparing with AUS model. Consequently, this experiment is shown that ultrasonic signal is gradually diminished as distances increases, the amplitude is improved as initial pressure increases, and ultrasonic sensor capable of transferring longitudinal wave is significantly affected by distance difference in CH₄ gas space.

中文翻译：

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超声波辅助测量天然气的效果

这项工作是一项实验性研究，旨在通过使用两个不同的超声传感器进行超声辅助测量，研究天然气车辆所需的气体燃料（CH ₄）特性。本文提供了包括能量转移过程，超声传播，灵敏度，幅度信号以及CH ₄关系的技术方法。密度和超声波信号。该实验由一个恒容室（CVC），两个不同的传感器（AUS和HSUS）以及气体燃料（甲烷）组成。实验条件为：在天然气空间中的初始压力为1〜4 bar，脉冲频率为7 Hz，共振频率为53.7 kHz以及测量距离为0.45〜0.85 m。结果，HSUS的高度为0.92 V，主宽度为4 cm，全宽度为12.7 cm，倾斜角为42.8°。重要的是，与AUS模型相比，要大大提高HSUS模型的高度和倾斜角度。因此，该实验表明，超声波信号随着距离的增加而逐渐减小，幅度随着初始压力的增加而改善，_4个气体空间。