Features for Modeling Irrecoverable Losses

AFT Fathom works almost exclusively with the concept of the loss factor, also known as the K-factor or resistance factor. In some Properties windows, other popular methods for specifying loss information are provided where they are consistent with the loss factor method. For example, you will find Cd (discharge coefficients) for orifices.

AFT Fathom has methods available for modeling irrecoverable losses with the Equivalent Length method with either user-defined equivalent lengths or NFPA 13 table data (which is the table on the Fittings & Losses tab on the Pipe Properties window). In order for the fittings and losses to be modeled as equivalent lengths, the toggle switch must be set to use Equivalent Lengths. Refer to the NFPA panel topic for more information on generating an NFPA Output Report.