驻波法声速测量仪的设计及数据处理方法  

Design of Sound Velocity Measurement Instrument based on Standing Wave Method and Data Processing Method

作　　者：石明吉[1] 罗鹏晖[1] 郭新峰[1] SHI Ming-ji;LUO Peng-hui;GUO Xin-feng(Nanyang Institute of Technology, Henan Nanyang 47300)

机构地区：[1]南阳理工学院,河南南阳473004

出　　处：《大学物理实验》2018年第3期85-89,共5页Physical Experiment of College

基　　金：南阳理工学院省示范校建设专项研究项目(SFX201718)

摘　　要：设计和制作了一款过程简单、测量误差小的全自动驻波法声速测量仪。实现对驻波场中各点声压大小的自动测量。利用该声速测量仪进行了声速测量实验并进行了数据处理。确定了声波的波长并计算出声速。大大减小了误差;根据波的时空双重周期性得到待测信号的频谱图,发现信号源频率不纯引起的次频共振现象是形成次峰和再次峰的重要原因。A set of automatic sound velocity measurement instrument based on standing wave method was designed and fabricated.Which can achieve automatic measurement of sound pressure at each point in the standing wave field,and determine wavelength and calculate sound speed.The error was greatly reduced.A frequency spectrum was obtained according to the space-time dual periodicity of wave. It revealed that the sub-maximum phenomenon was related with the sub-frequency resonance caused by the impure frequency of the signal generator.

关 键 词：声速测量仪 驻波法 有效值检测模块 傅里叶变换 次峰 次频 空间周期性 

分 类 号：O422.1[理学—声学]