Numerical Simulation of a Compartment Fire in a Nuclear Power Plant Containment Building

The current trend towards the increased use of risk assessment in the regulation of nuclear power plants will inevitably result in changes in the analysis of fire protection systems and the methods of analysis. Before fire protection can be regulated on a risk basis, a consensus must be reached on a number of issues. One key issue is what types of computational tools will be allowable for analyzing fire events, and what types of scenarios those tools will be approved for use. Reaching this consensus will require an understanding of the types of computational tools available and their inherent advantages and disadvantages. To aid with this understanding, three different methods of fire simulation are applied to an oil pool fire test in the HDR (Heiss Dampf Reaktor) containment test facility [1]. These methods are a hand calculation, the zone model code CFAST (Consolidated Model of Fire Growth and Smoke Transport) [2], and the computational fluid dynamics code FDS (Fire Dynamics Simulator) [3]. Each is applied to a steady-state portion of the test using, to the extent possible, the same set of input parameters. The results of the computation are compared to the test data. The comparisons show that each method is potentially suitable for use depending on the information required from the simulation. Each method will potentially have a role to play in risk based regulation depending on the scenario.