The NO_UPDATE_DEVICE_ID option means that time will stop updating and will remain fixed when the TEMP device turns TRUE. Line 2 defines a device (FREEZE TIME) that outputs time.This device turns TRUE when it measures a temperature of 200 C. Line 1 defines a device (TEMP), that will measure temperature.As an example, you can download the FDS verification problem hrr_freeze.fds (click the link, select the file, then click Raw to display only the file contents).įive lines from the hrr_freeze.fds file illustrate the basic concept. Before starting review Section 15.6.2 of the FDS User Guide. At this time, PyroSim does not support all the necessary details in the user interface, so we will demonstrate how to do this using the Additional Records feature in PryoSim.

Use the ramp feature to define a new HRR that follows the calculated value and then remains constant when the sprinkler activates.Ī more elegant way to accomplish this is to use the freeze option in FDS.Manually stop the model when a sprinkler activates.This post shows how to do this by automatically “freezing” the HRR at a constant value when a sprinkler activates. A common strategy when modelling a fire with sprinklers is to assume the fire will be held at a constant heat release rate (HRR) when the first sprinkler activates.

Pyrosim user guide