Comparison of axial velocity profiles for the 2-inch, s velence 0 double-bend model with available test data was seen to be good - the CFD picking up the flattening and undulating nature of the profiles. Comparison of the maximum swirl angle with published test PIV measurements showed that the CFD picked up the correct decay of swirl with distance from the bend. The CFD results for shift in C for a Venturi tube with a 10.5 deg convergent angle due to an upstream out-of-plane double-bend installation are within 0.05percent of the test data for beta velence 0.4 and, for the most part, within 0.1percent for beta velence 0.6. For beta velence 0.75, the CFD is within 0.3percent of the test data beyond x_(t)/D velence 5. However, the CFD fails to pick up a sudden upturn in the error curve closer to the exit of the bend.
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