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Air Quality

Gaussian Plume Air Quality Dispersion Model

Pasquill-Gifford stability classes A–F with Briggs plume rise. Real-time ground-level concentration maps, C_max, and x_max for stack emission scenarios.

Parameters
Presets
Emission rate Q50.0 g/s
Stack height H80 m
Exit velocity vs12.0 m/s
Stack diameter ds2.0 m
Wind speed u4.0 m/s
Stack gas temp Ts420 K
Ambient temp Ta293 K
Stability class
Terrain
Receptor distance x_r2.0 km
C_max (μg/m³)
x at C_max (km)
Receptor C (μg/m³)
Plume rise Δh (m)
Top View — Concentration Color Map (x-y)
Side View (x-z)
Ground-level C vs Downwind Distance
σy, σz vs Distance
Regulatory Comparison
WHO PM2.5 annual: 5 μg/m³
Japan PM2.5 annual: 15 μg/m³
Run calculation to assess

Gaussian Plume Model

$$C(x,y,z) = \frac{Q}{2\pi\sigma_y\sigma_z u}\exp\!\left(-\frac{y^2}{2\sigma_y^2}\right)\!\left[\exp\!\left(-\frac{(z-H)^2}{2\sigma_z^2}\right)+\exp\!\left(-\frac{(z+H)^2}{2\sigma_z^2}\right)\right]$$

Briggs plume rise: $\Delta h = \dfrac{1.6\,F_b^{1/3}\,x^{2/3}}{u}$, buoyancy flux $F_b = g\,v_s\,(d_s/2)^2\,(T_s-T_a)/T_s$

Engineering use: Environmental impact assessment, stack design, regulatory permit applications. Useful as a rapid pre-check before CFD simulations (OpenFOAM, Fluent). Benchmarks against ISO 9880 and AERMOD guidelines.