Method and device used for detecting spreading speed of ultrasonic waves in ultrasonic flow detection

The invention discloses a method and a device used for online detection of spreading speed of ultrasonic waves in ultrasonic flow detection by the time-difference method. The method includes: enabling to-be-tested gases to be freely spread into a static speed pipe when the to-be-tested gases flow through a pipe section of a measuring pipe provided with an ultrasonic transducer group, the static speed pipe is provided with ultrasonic transducers used for emitting and receiving ultrasonic waves into the static speed pipe, sonic path distance of the ultrasonic waves spreading in the static speed pipe can be obtained according to arrangement of the ultrasonic transducers on the static speed pipe, actual spreading time of the ultrasonic waves in the sonic path distance can be obtained by emitting and receiving the ultrasonic waves by the ultrasonic transducers in the static speed pipe. By the method and the device used for online detection of the spreading speed of the ultrasonic waves in ultrasonic flow detection by the time-difference method, online detection of the spreading speed of the ultrasonic waves is realized, and measuring accuracy is improved.