air dispersion modeling software free download

QUIC is comprised of a 3D wind field model called QUIC-URB, a transport and dispersion model called QUIC-PLUME, a pressure solver, QUIC-PRESSURE, and graphical user interface called QUIC-GUI.

Chemical, biological, and radiological (CBR) agent dispersion can be computed on building to neighborhood scales in tens of seconds to tens of minutes.

QUIC will never give perfect answers, but it will account for the effects of buildings in an approximate way and provide more realism than non-building aware dispersion models.

From their feedback we added multiple components, including source grouping, source configurations, multiple lane specification, and multiple output options.

Some of these new features are introduced as beta options in version 1.2.

These options can be selected by the user in the control file.

R-LINE is a part of EPA ORDs ongoing evaluation of air quality impacts in the near-road environment.

The research model is based upon a steady-state Gaussian formulation and is designed to simulate line type source emissions (e.g.

The current version of R-LINE R-LINE 1.2 -- is formulated for near-surface releases, contains new (field study and wind tunnel based) formulations for the vertical and lateral dispersion rates, simulates low wind meander conditions, includes Monin-Obukhov similarity profiling of winds near the surface and selects plume-weighted winds for transport and dispersion calculations.

The model utilizes the surface meteorology provided by the AERMET meteorological data preprocessor and includes user-friendly input requirements such as simplified road-link specifications.

Model simulation with integrated point sources has been formulated with careful attention to appropriately simulate line source emissions for receptors very near the source line.

This current version of the model is appropriate for flat roadways (no surrounding complexities); however, beta-option algorithms are included for simulating the near-source effects of complex roadway configurations (noise and vegetative barriers, depressed roadways, etc) and for simulating the line source emissions with an analytical approximation (rather than the numerical integration).

For guidance on dispersion models that are appropriate for regulatory use, see EPAs Guideline on AirQuality Models published as Appendix W to 40 CFR Part 51 (1122005) and EPAs Transportation Conformity Guidance for Quantitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas (December 2010; EPA-420-B-10-040).

These adverse effects, in combination with the fact that a significant portion of the population spending time at home, work or school within a few hundred meters of major roadways, support a need for dispersion modeling to capture the temporal and spatial variability of mobile source pollutants in the near-road environment.

A research effort was initiated to design and conduct wind tunnel and field studies to evaluate pollutant transport and dispersion of near-surface releases which provided new and expanded databases for development and evaluation of improved line source algorithms.

It is a research grade dispersion model that was primarily developed to support risk assessments and health studies related to near-road pollutants.

Reduced-form air quality modeling is a useful tool for examining what-if scenarios of changes in emissions, such as those due to changes in traffic volume, fleet mix, or vehicle speed.

Examining various scenarios of air quality impacts in this way can identify potentially at-risk populations located near roadways, and the effects that a change in traffic activity may have on them.

The dispersion routines used are based on the analytical version of R-LINE described in Snyder, et.

Atmos. Environ., 2013.

The user can modify the emissions for each road-link by changing the traffic composition, speed, andor traffic volume.

The air quality impact from a change in emissions due to changes in activity or fleet composition, or changes in representative meteorological conditions can be visually quantified for a select set of criteria pollutants and select mobile source air toxic (MSAT) species.

Additional information on the overall tool is available in Barzyk et.

Air Dispersion Modeling Software Free Download