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| Working Principle |
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The V-cone is a new kind of differential
pressure flowmeter, can be used to measure the various fluid
under different flowing condition within wide Reynolds number
range. With the same theory of other differential pressure
flowmeter, it is based on Bernoulli＞s theorem of energy conservation
for the continuous flowing fluid in a closed pipe. For ideal
fluid, fluid velocity is directly proportional to quadratic
root of differential pressure.
.jpg) V-cone
flow transducer has not only unique V-cone throttling contour
to extend measuring range of flowrate, but also special structure
of fluid conditioner. Therefore, requirement of straight pipe
is very low, totally different from other differential pressure
flowmeter which needs long straight pipe for fluid flowing.
V-cone flow transducer inherits advantages of good stability
and strong universality, while avoids limitations of traditional
differential pressure flowmeter.
Basic principle of V-cone flow transducer is V-cone and tapping ports coaxially installed in measuring pipe. Measuring tube and V-cone is designed and machined precisely.
When fluid passes V-cone, flowing fluid will interact with cone
and reshape the velocity profile before V-cone, fluid velocity
increasing and static pressure decreasing with local contraction.
Differential pressure ＠P will be produced before & behind
V-cone. High pressure (positive pressure) P1 is the static
pressure obtained at the tapping port in front of upperstream
fluid contraction, while, low pressure( negative pressure) P2 is
pressure at downstream obtained from tapping port at V-cone
central axis. Shown as right figure.
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Formula
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| Thereinto: |
| β ---------- Equivalent diameter ratio |
| D---------- Inside diameter of pipe |
| d ---------- Diameter of the largest cross
section of cone |
| qv --------- Volumetric flowrate |
| ρ -----------Fluid density under operating
condition |
| Κ---------- K factor |
| ε ---------- Expansion factor of gas |
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