Abstract：The integration error of the ultrasonic flowmeter is calculated in some theoretical disturbed flow profiles. The influence of the flow structure is analyzed, and its statistical regularity to the path number is studied. The results show that the integration error is directly related to the complexity of the flow profiles. It is believed from statistical analysis that the integration error decreases successively with the number of paths increasing, but not true for the certain flow profiles. The OWICS scheme has better accuracy than the Gauss-Jaccobi scheme, especially when the number of paths is limited.
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2011, Vol. 32 
