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DISPER

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Data 

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SOLUTIONS: DISPER  

solutions

advantages

Price

DEMO

 

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

 

 

Algorithms II ˇ DISPER software

                 

DEMO Download - Price

 

Downwind and Crosswind Distances

The model uses a Cartesian receptor network. All receptor points are converted to Cartesian (X,Y) coordinates prior to performing the dispersion calculations. In the Cartesian coordinate system, the X axis is positive to the east of the user-specified origin and the Y axis is positive to the north. The user must define the location of each source with respect to the origin of the grid using Cartesian coordinates. If the X and Y coordinates of the source are X(S) and Y(S), the downwind distance x to the receptor, along the direction of plume travel, is given by:

x=-[X(R)-X(S)]sin(WD)-[Y(R)-Y(S)]cos(WD)        (2)

where WD is the direction from which the wind is blowing. The downwind distance is used in calculating the distance-dependent plume rise and the dispersion parameters. The crosswind distance y to the receptor from the plume centerline is given by:

y=-[X(R)-X(S)]cos(WD)-[Y(R)-Y(S)]sin(WD)        (3)

Wind Speed Profile

The wind power law is used to adjust the observed wind speed, uref, from a reference measurement height, zref, to the stack or release height, hs. The stack height wind speed, us, is used in the Gaussian plume equation. The power law equation is of the form:

us=uref(hs/zref)p     (4)

where p is the wind profile exponent. Values of p may be provided by the user as a function of stability category and wind speed class. Default values are as follows:

Stability Category

Rural Exponent

Urban Exponent

A

0.07

0.15

B

0.07

0.15

C

0.10

0.20

D

0.15

0.25

E

0.35

0.30

F

0.55

0.30

The stack height wind speed, us, is not allowed to be less than 1.0 m/s.

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: SE (135 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: E (90 dregrees) and 70 degrees.

 

 

Canarina Algoritmos Numéricos, S.L.

Environmental software solutions

Canary Islands, Spain

e-mail: contact us

 

CANARINA: Home - Air pollution ˇ DISPER - Noise pollution ˇ CUSTIC - Water pollution ˇ DESCAR - Contact us

DISPER: Air pollution dispersion ˇ DISPER - Solutions - Data - Algorithms - Emissions - Graphs - ISC3 (VOL. 2)

SOLUTIONS: Air pollution dispersion ˇ DISPER - Software solutions - Software advantages - Price - DEMO download

COMMANDS: Input data I - Input data II - Input data III - Input data IV - Temporal average - Import and export data - Software 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