Thermal plumes above hot sources: characterization and capture efficiency

¹ LEMTA, CNRS UMR 7563, 2 avenue de la Forêt de Haye, BP 160, 54504 Vandoeuvre-lès-Nancy Cedex, France
² Institut National de la Recherche et de la Sécurité, Département Ingénierie des Procédés, Rue du Morvan, CS 60027, 54519 Vandœuvre Cedex , France

^a Corresponding author: Rene.Devienne@ensem.inpl-nancy.fr

Received: 30 March 2015
Accepted: 28 January 2016

Abstract

Many industrial processes use or generate thermal sources. The release of heat is generally accompanied by the dispersion of pollutants in the working area, which can lead to occupational diseases in the long-term. The characterisation of plumes stemming from thermal sources by natural convection is required to define the adequate dimensions for ventilation systems (fume collecting hoods and general displacement ventilation systems), used to clean air at work stations. The aim of this paper is to present the methods and techniques that can be used in ventilation engineering to analyse and manage industrial applications. The results presented concern the thermal and dynamic characterisation of plumes generated by different types of sources (horizontal disks, vertical cylinders, horizontal rectangular surfaces). New results concerning the efficiency of a fume extraction hood placed above a flat, rectangular thermal source was analysed as a function of the height and position of the hood in relation to the source and the extraction fan flow rate. These results are of practical interest. A numerical approach of temperatures in the proximal zone is also proposed.