Computational fluid dynamics analysis to assess performance variability of in-duct UV-C systems

Abstract

UV-C is becoming a mainstream air sterilisation technology, and is marketed in the form

Lagrangian modeling of inactivation of airborne microorganisms by in-duct ultraviolet lamps

“…10 represents the average UV dose ( D avg ) calculated on the y = 1.4 m sample plane for various luminous length of in-duct UV lamp and air supply velocity without considering UV inactivation. Average UV dose ( D avg ) was the arithmetic mean of UV dose of airborne microorganisms sampled in-plane ( y = 1.4 m) expressed as [ 42 ]: where n is the total number of particles sampled in-plane and D i represents the UV dose of particle i . To calculate the average UV dose, it was supposed that airborne microorganisms were immune to ultraviolet disinfection.…”

“…In the modeling, the physical duct model was built with 610 mm × 610 mm × 1830 mm dimensions based on the literature [ 42 , 50 ]. The duct was then meshed with 348, 400 non-uniform structure computational grid cells.…”

“…Table 4 represents the comparison of present modeling and EPA experiment measurement. Based on the table, the numerical results of literature [ 42 , 50 ] are also indicated. It was different from Section 3.3 that D avg in Table 3 has been considered UV disinfection.…”

“…EPA calculated D avg through B. atrophaeus 's data with Z = 0.016 m 2 /J in their cases. In the present modeling, Z values are also utilized which were recommended by EPA and Capetillo et al (2015) [ 42 , 49 ]. Capetillo et al (2015) [ 42 ] also used the arithmetic mean of UV dose of all particles sampled in the outlet (Eq.…”

“…Pichurov et al (2015) found Lagrangian modeling was more accurate than Eulerian modeling [ 41 ]. Capetillo et al (2015) investigated the performance of multi UV lamps in the ventilation duct using the CSFP method based on the Environmental Protection Agency (EPA) UVGI experiment [ 42 ]. In the above three numerical works, bacteria viability was all determined via bacteria survival fraction probability.…”