CFD for mixing efficiency in commercial and industrial advanced air oxidation

Sammanfattning: Ozone treatment of pollutants in air is a relatively young technology with limited literature available. To the authors knowledge no literature discussing simulations of commercial ozone treatment without UV-lamps in gas phase has been published up to this point.The purpose of this project was to identify issues and propose recommendations related to the distribution of ozone in industrial ducting and the injection of ozone into commercial ducting. The injection rate of the ozone mixture is small relative to the flow of the treated air stream. In such cases ozone is easily swept away and confined to a limited section of the ducts, affecting overall efficiency. The injection inlet and ducting were simulated together in both 2D and 3D environments using COMSOL Multi-physics with CFD, CAD and transport of diluted species modules.Improving mixing in industrial ducting was simple in comparison to the commercial ducting where the flow is complex. For the commercial application simulations showed that the mixing efficiency varies greatly between injection positions. Based on CFD data in the commercial ducting two models for injection point analysis were developed.2D and 3D simulations showed different result for injections inside the main duct, the 3D case could properly simulate rotating flows inside the main duct which makes certain injection points in the main duct more effective that predicted in 2D.This master thesis project was done in cooperation between Royal Institute of Technology and Ozonetech in Sweden.