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SOLUTIONS: DISPER  

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COMMANDS:

Input data I

Input data II

Input data III

Input data IV

average

Import

commands

ALGORITHMS:

Algorithms I

Algorithms II

Algorithms III

Algorithms IV

Algorithms V

Algorithms VI

Algorithms VII

Algorithms VIII

Algorithms IX

Algorithms X

EMISSIONS:

Emissions I

Emissions II

Emissions III

Pollutants I

Pollutants II

GRAPHS:

Graphs I 

Graphs II

Graphs III 

Graphs IV

The Decay Term (D)

The Decay Term is a simple method of accounting for pollutant removal by physical or chemical processes. It is of the form:

D=exp(-psi x/u_s)    for psi > 0   (36)

D=0                for psi = 0   (37)

where:

psi= the decay coefficient (s^-1) (a value of zero means decay is not considered)

x= downwind distance (m)

For example, if T_1/2 is the pollutant half life in seconds, the user can obtain y from the relationship:

psi=0.693/T_1/2          (38)

The default value for psi is zero. That is, decay is not considered in the model calculations unless y is specified. However, a decay half life of 4 hours (y = 0.0000481 s^-1) corresponds to SO₂ when modeled.

Algorithms I - Algorithms II - Algorithms III - Algorithms IV - Algorithms V -  Algorithms VI - Algorithms VII - Algorithms VIII - Algorithms IX - Algorithms X

Air pollution map (XY-Plane) produced by continuous discharge in time (three stacks). The red colour represents high pollutant concentrations. Wind: W (270 degrees).

Air pollution map (XY-Plane) produced by continuous discharge in time. The fucshia lines represents a stacks in the XY-Plane. The red colour represents high pollutant concentrations. Winds: NE (45 dregrees) and 145 degrees.