La. Xu et al., A CLAMP-ON ULTRASOUND CROSS-CORRELATION FLOWMETER FOR LIQUID-SOLID 2-PHASE FLOW MEASUREMENT, FLOW MEASUREMENT AND INSTRUMENTATION, 5(3), 1994, pp. 203-208
A clamp-on pulsed ultrasound cross-correlation flowmeter has been deve
loped by the authors which can measure the mixture velocity of liquid/
solid two-phase flows. Small, well-dispersed solids exist in the calib
ration and test liquids, which for a given mixture have consistent sli
p. Allowance for this slip in determining mixture velocity is made by
the meter factor obtained during specific calibrations. The flowmeter
has been calibrated in a horizontal pipe by comparison with an electro
magnetic flowmeter using a well-mixed, low concentration paper pulp (c
oncentration 0.4% by weight, average solids density approximately 1100
kg m-3) as the measured medium. The maximum deviation between these t
wo meters is +/-4.8% with a confidence level of 99.73%. One prototype
of this flowmeter was installed on a pulp pipeline at a paper mill for
long-term reliability trails. The results are encouraging. A second p
rototype was installed in series with an oval gear volumetric flowmete
r on a pipeline, in which very high viscosity crude oil flowed. Result
s show that the cross-correlation flowmeter worked reliably even at ve
locities less than 0.3 m s-1; the maximum difference between the two t
ypes of meter was less than +/-3%.