...
A ratio between actual volumetric flowrate through the the real orifice and volumetric flowrate estimate through the ideal orifice:
...
...
The discharge coefficient
is a function of a
choke narrowing ratio
and
Reynolds number in the pipe:
LaTeX Math Block |
---|
|
C_d = C_d(\beta, {\rm Re}) |
where
LaTeX Math Block |
---|
|
{\rm Re} = \frac{v \cdot D}{\nu} = \frac{4 \, q}{\pi \, D \, \nu} |
where
It can be estimated for popular popular choke types or tabulated in laboratory.
...
The most popular engineering correlation covering all ISO 5167 various tapping arrangements is given by Discharge coefficient @ model ISO5167:
LaTeX Math Block |
---|
|
C_d = C_{d, \infty}(\beta) + b(\beta) \cdot 0.5961 + 0.0261 \cdot \beta^2 - 0.216 \cdot \beta^8 + 0.000521 \cdot \left( \frac{ 10^6 \, \beta }{ {\rm Re}^{-n} |
...
...
...
...
See also
...
Physics / Fluid Dynamics / Pipe Flow Dynamics / Pipe Flow Simulation (PFS) / Pipeline Choke @model
[ Orifice Plate Expansion Factor @ model ]
Pipeline Engineering / Pipeline / Choke
Reference
...
ISO5167 – Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full
M J Reader-Harris and J A Sattary, THE ORIFICE PLATE DISCHARGE COEFFICIENT EQUATION - THE EQUATION FOR ISO 5167-1, National Engineering Laboratory, East Kilbride, Glasgow, 1996
J E Gallacher, ORIFICE PLATE DISCHARGE COEFFICIENT EQUATION, Shell Pipe Line Corporatio, Paper 5.1, NORTH SEA FLOW MEASUREMENT WORKSHOP, 23-25 October 1990 Anchor |
---|
Stolz | StolzStolz,J.,"A Universal Equation for the Calculation of Discharge Coefficient of Orifice Plates";, Proc. Flomeko 1978- Flow Measurement of Fluids,H. H. Dijstelbergenand E. A.Spencer(Eds), North-HollandPublishingCo.,Amsterdam(1978), pp 519-534
...