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DISPER:

DISPER

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Data 

Algorithms

Emissions 

Graphs  

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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

Plume Rise Formulas

The plume height is used in the calculation of the Vertical Term. The distance dependent momentum plume rise equations are used to determine if the plume is affected by the wake region for building downwash calculations. 

Stack-tip Downwash

In order to consider stack-tip downwash, modification of the physical stack height is performed. The modified physical stack height h_s is found from:

h_s’=h_s+2d_s[(v_s/u_s)-1.5]   for  v_s<1.5u_s      (5)

or

h_s’=h_s                   for v_s> o =1.5u_s   (6)

where h_s is physical stack height (m), v_s is stack gas exit velocity (m/s), and d_s is stack top diameter (m). If stack tip downwash is not considered, h_s’= h_s in the following equations.

Buoyancy and Momentum Fluxes

For most plume rise situations, the value of the Briggs buoyancy flux parameter, F_b (m⁴/s³), is needed

F_b=gv_sd_s²(DT/4T_s)    (7)

where DT = T_s - T_a, T_s is stack gas temperature (K), and T_a is ambient air temperature (K).

For determining plume rise, the momentum flux parameter, F_m (m⁴/s²), is calculated based on the following formula:

F_m=gv_s²d_s²(T_a/4T_s)    (8)

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 (two stacks). The red colour represents high pollutant concentrations. Wind: S (180 degrees).

Air pollution map (XY-Plane) produced by continuous discharge in time. The red colour represents high pollutant concentrations. Winds: NE (45 dregrees).

Canarina Algoritmos Numéricos, S.L.

Environmental software solutions

Canary Islands, Spain

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

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

SOLUTIONS: Air pollution dispersion · 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