Comparative research was carried out on the inherent error of four commonly used inherent in the Reynolds number interval 1.0×10
3
-1.0×10
7
according to the inherent error introduced by the numerical integration of ultrasonic flowmeters during the measuring process. From the mathematical model of an ultrasonic flowmeter and the universal velocity distribution of a fully developed pipe flow
the error of integrations of a flowmeter with two to five acoustic paths was calculated
and the error distribution curves were obtained. The results show that inherent error introduced by the integration decreases with an increase in the number of acoustic paths. When the Reynolds number is higher than 1.0×10
5
all the integrations' importing error is gradually stable. However
Gauss
-Legender has obvious advantages when the number of acoustic paths is unlimited and the maximum importing error occurs in the flow detecting range. Tailored has a smaller error than the others in the Reynolds number range of 8.0×10
3
-4.0×10
5
. Owics is more suitable for the flow measurement where the number of acoustic paths is limited and the Reynolds number is higher than 4.0×10
5
.
关键词
Keywords
references
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