CHARM

The CHARM software is an application that calculates and predicts the movement and concentration of airborne plumes from released chemicals due to air dispersion and transport; thermal radiation impacts from BLEVEs, pool fires, and jet fires; and explosion overpressures from mechanical and vapor cloud explosions. Source terms are calculated from observable data input (e.g. temperature, pressure, hole size, etc.). Results are available in tables as well as 2D and 3D graphics.

CHARM comes in two versions. Both are available under a single license. One version is a flat terrain puff model. The other is a complex terrain grid model. The flat terrain version lends itself to fast what if analysis. Input parameters can be easily changed with the effects seen quickly. The complex terrain version is designed for more detailed analysis.

 

Purchase of a new license includes technical support for a year. After the first year paying an annual maintenance fee continues the technical support and allows the use of all updates.

The input required for a scenario to be run is a release description and meteorological parameters. For the complex terrain version, a grid defining the region to be calculated also needs to be supplied.

Impact (concentration, thermal radiation, or explosion overpressure) history at specified locations can also be generated. The user can either double click in the window or specify a distance and angle from the release site for calculating the impact history. Both versions provide 3D displays of the impact area with maps.

The flat terrain version of CHARM is designed to simulate the release from a single source. The complex terrain version is much more complete and can handle multiple sources and species. They both provide calculations of air transport and dispersion, mechanical and vapor cloud explosions, and BLEVE, jet fire, and pool fire radiation.

Visit YouTube to see some videos on using CHARM, especially the complex-terrain version.