A single fitting in the database does not have a single fixed loss coefficient. The coefficient changes fluidly based on: The ratio of branch flow to common flow. Area Ratios ( ): The geometric transitions within the fitting. Reynolds Number: Accounting for turbulent behavior.
If you own a legitimate copy of the legacy ASHRAE DFDB and it fails to run on a modern operating system, try these standard troubleshooting steps instead of seeking an unverified web patch: ashrae duct fitting database pdf patched
Version 6.0 is the current standard, featuring pictorial outlines and real-time calculation updates for round, rectangular, and flat oval fittings. Supporting Papers & Design Guides: A single fitting in the database does not
The ASHRAE Duct Fitting Database (DFDB) is a software application that contains loss coefficient tables for more than 200 round, rectangular, and flat oval duct fittings, accompanied by pictorial outlines of each fitting configuration. For any given fitting, users can enter flow rate and fitting information to obtain loss coefficient data and associated pressure loss calculations—a capability essential for accurate HVAC system design. Reynolds Number: Accounting for turbulent behavior