CANARINA:
DISPER:
SOLUTIONS: DISPER
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ALGORITHMS:
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The mathematical model that the software uses provides options to model emissions from a wide range of sources that might be present at industrial areas and urban areas. The model is analogous to ISC3 from EPA. The basis of the model is the straightline, steadystate Gaussian plume equation, which is used to model simple point source emissions from stacks, roads, storage piles and conveyor belts. Emission sources are categorized into three basic types of sources: point sources, line sources and area sources. The algorithms used to model each of these source types are described in detail in the following sections. The DISPER dispersion model accepts meteorological data records to define the conditions for plume rise and transport. The model estimates the concentration value for each source and receptor combination and calculates userselected averages. Point source emissions The model uses a steadystate Gaussian plume equation to model emissions from point sources, such as stacks. The Gaussian Equation The model for stacks uses the steadystate Gaussian plume equation for a continuous elevated source. For each source, the origin of the stack coordinate system is placed at the ground surface at the base of the stack. The x axis is positive in the downwind direction, the y axis is crosswind (normal) to the x axis and the z axis extends vertically. The fixed receptor locations are converted to each source's coordinate system. The hourly concentrations calculated for each source at each receptor are summed to obtain the total concentration produced at each receptor by the combined source emissions. For a Gaussian plume, the hourly concentration at downwind distance x (meters) and crosswind distance y (meters) is given by: c =(Q K V D/2 pi u_{s }sig_{y }sig_{z}) exp[0.5(y/sig_{y})^{2}] (1) where: Q= pollutant emission rate (mass per unit time) K= a scaling coefficient to convert calculated concentrations to desired units (default value of 1 x 10^{6 }for Q in g/s and concentration in µg/m^{3}) V= vertical term (See Section 1.1.6) D= decay term (See Section 1.1.7) sig_{y},sig_{z}= standard deviation of lateral and vertical concentration distribution (m) (See Section 1.1.5) u_{s}= mean wind speed (m/s) at release height (See Section 1.1.3)
Algorithms I  Algorithms II  Algorithms III  Algorithms IV  Algorithms V  Algorithms VI  Algorithms VII  Algorithms VIII  Algorithms IX  Algorithms X
Air pollution map (XYPlane) produced by continuous discharge in time. The fucshia lines represents a stacks in the XYPlane. The red colour represents high pollutant concentrations. Winds: E (90 dregrees) and S (180 degrees).
Air pollution map (XYPlane) 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 email: contact us
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
