Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
An Approximate Puff Combination Model for Heavy Gas Dispersion
Submission Author:
Edson Chiaramonte , RS
Co-Authors:
Edson Chiaramonte, Renato Letizia Garcia, sergio meth
Presenter: Edson Chiaramonte
doi://10.26678/ABCM.COBEM2023.COB2023-1041
Abstract
Currently, much effort is being spent on developing realistic methods for assessing the consequences of an accidental release of hazardous materials. The production, transport and storage of large amounts of gases, explosives or toxic substances can pose a serious hazard. The so-called heavy gas release has a dispersion behavior in the atmosphere that differs from that of neutral gas, as the excess density causes greater lateral dispersion and a greater initial fall of the cloud due to the effect of gravity, which is why these releases tend to form thicker clouds. close to the ground, with a width much greater than its height (a large top surface). The objective of this research is to develop a dispersion model that has a quick response in the occurrence of heavy gas leaks into the atmosphere. This article presents an approximate model to represent the different types of heavy gas releases in terms of time. These types are continuous, intermittent, and instant release. The model applies the process of summing and combining instantaneous releases (the so-called “puffs” model) to represent continuous and intermittent releases. That is, a set of “puffs”, in the cylindrical shape, are released in series. The model that represents a “puff” is showed, it is a set of algebraic and ordinary differentials equations for the variables radius, mass, air intake, temperature, and the density of the “puff”. It is also shown the association model of “puffs” that is constituted by the dispersion model and the transport of an instantaneous release, the model that estimates the thermodynamic properties, the model that makes the release of “puffs” in the source, and the process addition and combination of “puffs”. In the last part of the article, the numerical results obtained with the model are compared, from a statistical analysis, with the field experimental values of continuous releases of heavy gases obtained in the literature.
Keywords
heavy gases, atmospheric dispersion, box models
