An educational tool to visualize Plume and Puff dispersion.
This simulation tool allows you to explore two fundamental types of Gaussian dispersion models: the **Continuous Plume Model** and the **Instantaneous Puff Model**.
This model is used for sources that emit pollutants at a constant rate over a long period. It assumes a steady-state condition where the shape of the plume downwind does not change with time.
$$C_{plume}(x,y,z) = \frac{Q}{2\pi\sigma_{y}\sigma_{z}u} \exp\left(-\frac{y^{2}}{2\sigma_{y}^{2}}\right) \left[ \exp\left(-\frac{(z-H_{eff})^{2}}{2\sigma_{z}^{2}}\right) + \exp\left(-\frac{(z+H_{eff})^{2}}{2\sigma_{z}^{2}}\right) \right]$$
This model is used for a single, instantaneous release of a pollutant. The resulting "puff" travels downwind and expands over time. The concentration depends on the time elapsed since the release.
$$C_{puff}(x,y,z,t) = \frac{Q_{puff}}{(2\pi)^{3/2} \sigma_x \sigma_y \sigma_z} \exp\left[-\frac{(x-ut)^2}{2\sigma_x^2}\right] \exp\left[-\frac{y^2}{2\sigma_y^2}\right] \left[ \exp\left(-\frac{(z-H_{eff})^{2}}{2\sigma_z^2}\right) + \exp\left(-\frac{(z+H_{eff})^{2}}{2\sigma_z^2}\right) \right]$$
Note: High grid point counts can be computationally intensive.