Title: Computational fluid dynamics modelling of UR-UVGI lamp effectiveness to promote disinfection of airborne microorganisms
Authors: Mohammad Heidarinejad; Jelena Srebric
Addresses: Department of Mechanical Engineering, The Pennsylvania State University, 127 Reber Building, University Park, PA 16802, USA. ' Department of Architectural Engineering, The Pennsylvania State University, 104 Engineering Unit A, University Park, PA 16802, USA
Abstract: This paper focuses on using computational fluid dynamics (CFD) modelling methods to study the effectiveness of upper-room ultraviolet germicidal irradiation (UR-UVGI) lamps in healthcare facilities. This work develops and uses simplifications for boundary conditions in CFD, while details of UR-UVGI lamps and microorganism characteristics were obtained from existing experimental studies. Three approximation methods were developed to implement the effects of UR-UVGI lamps on microorganism dispersion patterns represented with the Eulerian and the Lagrangian methods in CFD simulations. Then, a non-dimensional parameter, the UR-UVGI effectiveness, was introduced to study the effectiveness of UR-UVGI lamp(s) disinfection process with respect to the combined effect of UR-UVGI lamp(s) and ventilation systems. Although comparisons of results obtained from CFD simulations and experimental data show that local microorganism numbers/concentrations depend on boundary condition modelling methods, global variables such as the fraction of remaining microorganisms remain relatively unchanged and in a good agreement with the measured data.
Keywords: ultraviolet germicidal irradiation; UVGI; UR-UVGI lamps; lamp effectiveness; computational fluid dynamics; CFD; airborne microorganisms; healthcare facilities; boundary condition modelling; disinfection; dispersion patterns; UV radiation; simulation; ventilation systems.
World Review of Science, Technology and Sustainable Development, 2013 Vol.10 No.1/2/3, pp.78 - 95
Received: 05 Nov 2011
Accepted: 27 Jul 2012
Published online: 28 Feb 2014 *