This module is an add-on SIDLAB Acoustics. This is a very quick 1D tool to calculate the pressure drop introduced by the designed muffler system. It calculates the flow distribution and pressure drop inside the network using a two-port formulation, and feeds the results into the acoustic calculation in SIDLAB Acoustics. The acoustic performance of some elements like perforates is very dependent on the amount of flow inside the element. SIDLAB Flow uses the same network built in SIDLAB Acoustics.