Volumetric gas monitoring through a DSA laser network for the estimation of the gas emission flux by surface sources: Methods and simulation results

A measurement approach for estimating the emission flux by a surface-distributed source, based on the use of IR laser measurements over optical links and atmospheric diffusion models is presented. An ad hoc disposition of the optical links close to the emission area allows to measure gas concentration over a closed surface corresponding to an air volume that covers the whole emission area. The real time concentration measurements over this closed surface, associated to suitable diffusion models, allow us to estimate the emission flux of the area under exam. The diffusion model to be applied strictly depends on the current atmospheric conditions, therefore it requires the knowledge of the main atmospheric parameters. In this paper we present some simulation results about a system for the surface flux monitoring assuming the faces of a parallelepiped the surfaces interested by laser measurements. The closed surface is therefore defined by 5 of its sides, while the 6th is the emission surface. We discuss some estimation results using diffusion models where the air diffusion and transportation phenomena are due mainly to the wind strength.