PROPAGATION TIME DIFFERENCE TYPE ULTRASONIC FLOWMETER

PROBLEM TO BE SOLVED: To accurately measure a flow rate of each measured fluid, without increasing memories for acquiring data, when the plurality of kinds of measured fluids different in temperatures and kinds flow switchedly in a flow passage tube body. SOLUTION: This ultrasonic flowmeter is provided with a digital data processor 6 for calculating the flow rate based on a difference between ultrasonic propagation times in an upstream direction and a downstream direction by switching transceiving functions of two ultrasonic oscillators 2a, 2b attached to the flow passage tube body 1 of the measured fluid, the digital data processor stores a plurality of sets of parameter sets concerned in flow rate measurement of the fluid in the memory, receives a logic input corresponding to the kind of the measured fluid from an outside to call out from the memory the corresponding parameter set out of the plurality of sets of parameter sets, and conducts prescribed data processing based on the parameter set to calculate the flow rate. COPYRIGHT: (C)2005,JPO&NCIPI