IR laser network and tomography for the greenhouses gas emission control by sensitive areas: performance analysis of the laser network topologies by software simulations

A real time approach for estimating the greenhouses gas emission flux by a surface-distributed source based on the use of IR laser measurements over optical links has been recently proposed. An ad hoc arrangement of the laser optical links allows to measure gas concentration over a closed surface corresponding to a volume that covers the emission area. The closed volume is defined by 5 of the parallelepiped's surfaces, while the 6th is the emission surface. The emission flux is obtained by applying the mass balance to the parallelepiped after having estimated the gas concentration over the five sides. The gas concentration field over the five plane surfaces of the monitoring volume is obtained by ad hoc tomographic processing of the laser measurements. Assuming realistic network topologies we simulate the whole emitting and measurement scenario using a self-developed software tool based on Gaussian diffusion models for the simulation of the gas concentration in atmosphere close to the emission area. Through a Monte Carlo approach we compute specific error parameters that are then used as performance indices of the proposed flux estimation method, as a function of the measurement topology network and the gas emitting conditions.