A comparison between a plume path model and a virtual point source model for a stack plume

✍ Scribed by Ooms, G. ;Mahieu, A. P.

• Publisher: Springer
• Year: 1981
• Tongue: English
• Weight: 781 KB
• Volume: 36
• Category: Article
• ISSN: 0003-6994
• DOI: 10.1007/bf00411893

✦ Synopsis

Some years ago we developed a theoretical model for the calculation of the rise of a stack plume in the atmosphere. Recently we have extended this model in such a way that the ground level concentration of gases emitted by a stack can also be calculated. The cross-section of the plume, which was originally assumed to be a circle, is now assumed to be an ellipse. The height-to-width ratio of the ellipse is chosen in accordance with full-scale data. The entrainment of air into the plume due to atmospheric turbulence can now be calculated not only for neutral atmospheric conditions, but also for stable and unstable conditions.

Predictions of the ground level concentration made with this model have been compared with predictions made with the often used virtual point source model. For neutral and unstable atmospheric conditions the agreement is rather good. For stable conditions the differences can be rather large. The sensitivity of the ground level concentration with respect to the atmospheric stability condition, the stack height, the plume exit momentum flux and the plume exit buoyancy flux has also been investigated with the aid of the model. The influence of the plume exit momentum flux is negligible; however, the influence of the other parameters can be large.