Comparative analysis of CFD P vs. measured P for compressed flexible ducts

Computational fluid dynamics (CFD) analysis was used to study the pressure drop behavior of 6-inch-diameterflexible duct with a single helix core. The simulation used a positive pressure, blow-through configuration. There are two objectives of this study. First is to set up a three-dimensional modeling and mesh generation method of flexible duct, which represents the duct geometry and provides visual information on the flow patterns. Second is to calibrate the CFD model by comparing simulation data with laboratory data for the same duct configuration. Simulations, based on different duct compressions including fully stretched, 4% compression, 15% compression, and 30% compression, were conducted under a range of air volumes from 70 to 160 cfm in 10 cfm increments. The internal mesh was configured to match the axial length of the spiral. Static pressure data were taken from the CFD analysis for these periodic points. The data from the central axis were then compared to the laboratory data. The results suggest that the CFD model can simulate pressure drop (P) within about 5% to 10% of the measured values for flexible ducts in the board supported configuration. 2007 ASHRAE.

Comparative analysis of CFD P vs. measured P for compressed flexible ducts Conference Paper