| Feature | Description | |------|------| | | Over 200 entries covering elbows, transitions, tees, offsets, wyes, and more | | Pictorial Outlines | Each fitting includes a schematic drawing, making it easy to visually confirm the correct fitting type | | Dual Unit Support | Full support for both I‑P (Imperial) and SI (metric) units with automatic conversions | | Project Management | Fittings can be saved into project files; files are small enough to be easily stored and transferred | | Custom Fitting Support | Users can add or modify K‑values for project‑specific configurations | | Data Export | Export results as CSV or XML for integration into Excel, Revit, or other BIM/CFD tools | | Air Property Adjustment | Adjust air properties for any temperature, relative humidity, or altitude |
To maximize the utility of the database during a project design phase, engineers follow a standardized workflow:
Inch-Pound system (CFM, inches of water gauge, feet per minute). SI Units: International System of Units ( , Pascals, meters per second). 4. Dynamic Calculation Engine
The accuracy of the DFDB is underpinned by rigorous testing standards. , "Method of Testing to Determine Flow Resistance of HVAC Ducts and Fittings," provides the uniform laboratory testing methods used to measure airflow resistance. The data from at least six major research projects based on this standard directly feed into refining and updating the Duct Fitting Database. This scientific backbone ensures that the loss coefficients you use are based on empirical evidence.
: The precise coefficients derived from Version 6.00.05 can be manually input into Revit or third-party duct sizing tools to override default, inaccurate calculations.
Engineers use the ASHRAE Duct Fitting Database to calculate , which is vital for selecting appropriate fans and air handling units (AHUs). Loss Coefficients ( Cocap C sub o
Fixed mathematical equations for and aligned database tables with source text files for SD5-3 , CD3-3 , and CD3-5 .
The primary function of Version 6.00.05 is to quantify the energy losses that occur as air moves through various duct components. Straight ducts exhibit friction losses, but significant pressure drops occur at fittings—where the air changes direction (elbows), changes size (transitions), or enters/exits equipment.
: Increased allowable input ranges for dimensions like diameter, height, and width for several fittings, including SR4-3 , ER4-3 , and CR3-17 .
utilizes the ASHRAE Duct Fitting Database to look up loss coefficients when performing pressure loss calculations for duct systems. The DFDB data ensures that Revit models reflect industry‑standard pressure loss behavior, making simulations more reliable.
The ASHRAE Duct Fitting Database is a comprehensive digital catalog of resistance coefficients (K‑values) for hundreds of standard duct fittings. It includes detailed loss coefficient tables for more than , each accompanied by a clear pictorial outline. For any given fitting, engineers enter the flow rate and relevant dimensional data, and the software instantly returns the loss coefficient along with the associated pressure drop.