Objective:
The main objective of this analysis is to determine the measurement error in Flare Gas Ultrasonic Meter installations using CFD tool.
Design Approach:
The flow is assumed to be steady and incompressible throughout. The realizable k-turbulence model has been used in most cases.
CFD modeling of the ultrasonic meter is undertaken in three separate stages:
Bend model.
Baseline model
Meter model
Analysis of the bend and baseline models has been run in order to generate the inlet boundary conditions for the meter model at each given flow rate.
Conclusion:
The CFD simulations agree well with the test data for the diametric path position and predict the correct trend with distance from the bend. The predictions are within 2 – 6 % of the measurements in all cases.
A single bend generates an asymmetric flow profile that also has non-axial velocity components. Curvature of bend causes the flow to be thrown to the outside of the pipe, creating a skewed velocity profile which will then slowly develop down the pipe.
