Advanced software for modelling dense gas dispersion
Model input data
- Wind speed, height and bearing.
- Atmospheric pressure, humidity, air temperature, Monin-Obukhov length or Pasquill-Gifford stability.
- Roughness length.
- Surface temperature.
- Chosen from materials database (supplied) or user defined.
- Puff, plume, transient, jet.
- Aerosol (flashing), thermal or isothermal releases.
The pool uptake model uses liquid spill evaporation/boil-off information to calculate plume uptake. To simplify pool uptake, GASTAR interfaces with CERC's comprehensive pool spill model LSMS.
- Width, mass (flux), temperature, aerosol fraction.
- Height and direction for jets.
- Rectangular and/or circular buildings.
- 2-dimensional walls (solid) and fences (porous).
- Topography through segmented slopes with spatially varying properties (inclination, roughness length, wind speed).
Model output data
Cloud properties along the centre-line
- Time and xyz-position, distance travelled.
- Concentration, mass fraction, width, height, volume, velocity.
- Mass, enthalpy, temperature, density, aerosol fraction, Richardson number.
- Leading and trailing edges (for instantaneous releases).
- Downwind and crosswind dimensions (for instantaneous releases).
The user may choose to add extra output steps by time and/or position, to get the maximum range to particular concentration, gridded concentration output.
Additional output for available for specified output points
- Concentration-time histories.
- Dose and toxic load.
Additional output for available for specified output times
- Flammable output: LFL and half-LFL range, downwind and crosswind radius, maximum height, flammable volume and mass.
Output for GASTAR may be presented graphically with its integrated free-floating graphics screen (x-y plots for all cloud properties; flammable output plots). A tabulated record of user input and all model output is also available.