圆柱定程干涉法声速测量原理与实验系统研制

Fundamental Theory and Apparatus for Speed of Sound Measurement System Using Cylindrical Resonator

气相声速是目前可测量的最精确的热物性之一,圆柱定程干涉法是极有应用前景的测量方法。本文分析了圆柱定程干涉法测量气相声速的实验原理,在此基础上研制了一套新的实验系统,由共鸣腔、压力仓、共振频率测量系统、温度和压力测量系统以及数据采集与控制系统组成。实验系统综合考虑了多种非理想因素的影响,提高了共振频率测量的信噪比,降低了测量不确定度。

Speed of sound is an important thermophysical property which can be measured very precisely.Cylindrical resonator is a promising approach to measure speed of sound accurately.Based on the fundamental theory of cylindrical resonator,a new experimental system was built including the resonator and pressure vessel,the frequency measurement system,the temperature and pressure measurement system and the data acquisition system.Great efforts have been made to obtain high signal-to-noise performance.