Program description

Fluidyn-PANACHE is a computing program of the French firm Transoft Int. that uses the model CFD, based on laws of conservation of energy, mass and momentum.

Program Fluidyn-PANACHE is determined for dispersion of pollutants, escaping into environmental air during different climatic and geographic conditions.

It enables simulation of the following effects:

	short and long-term influence of pollutants
	simulation of accidental conditions and determination of anticipated dispersion of pollutants

Input data

Results are presented in visual form, displayed chronologically in the range from several minutes to days at various climatic conditions. The display can be as vector representation, showing the streaming characteristics, or as contour plan showing distribution of important values (e.g. concentration of pollutants).

The representation of single variable can be selected in the form of:

	lines - displaying constant levels of pollutants in selected units
	surfaces - displaying the constant level of pollutants in three-dimensional space

In the case of result displaying as lines it is possible to show more concentration levels in one view or to show only one concrete specified concentration level.

The visual display of results with surfaces is suitable to show the distribution of concentration in three-dimensional space. As variables can be selected the concentration of the individual simulated components or the dynamic variables.

Program description

The program MODIM uses the dispersive model ISC2 that enables to model the dispersion of emissions from broad range of sources; it can represent a big industrial complex of pollutants´ sources. The ISC2 model applies the Gaussian formula of smoke lug dispersion, the Pasquilli-Gifford dispersion parameters for 6. Stability categories of the atmosphere and Briggs equations to calculate the smoke lug rise. The effect of a high structure, near to the source and the rate of chemical transformation of pollutants in environmental air can be included into the calculation.

The input for the model ISC2 is the wind rose to define the weather conditions for smoke lug rise, transport and diffusion of emission. The model for each point of the given network, calculates the concentration contribution of emission from each source for all values of meteorological data.

Input data

	Input data of the source
	Meteorological parameter
	Computing area and reference points
	Calculation parameter

The dimensions and steps of calculation are defined. It is possible to transfer the bit map of documentation into the program.

Output from program MODIM

The program is computing the maximum and average concentrations, at the network points or at input reference points, for each source or set of selected chimneys. The user can decide about the given form of results, from the following arrangement :

average concentration of all input chimneys
average concentration of selected chimneys
contribution of pollution from selected chimneys
overload of the entered limit value by the user (maximum 4 limit values)
stability degree
wind velocity
wind direction
short-term maximum (30 minutes concentration)
The final characteristics are available in tabular or graphical form.