Feedback control of particles in fluid media.
O'Shaughnessy PT; Hemenway D; Haugh LD
Department of Civil and Environmental Engineering, College of Engineering and Mathematics, University of Vermont, Burlington, Vermont 1996 Jan; :1-98
The response of environmental test chamber aerosol concentration levels to various changes in aerosol generator speed and chamber air flow rate was investigated. The use of statistical process control techniques to implement automatic feedback control of the instantaneous concentration levels by manipulation of the generator speed and dilution air flow rate was evaluated. A personal computer was used to control the output rate of an aerosol generator and air flow through the chamber, and was also connected to an aerosol monitor to record chamber aerosol concentrations. Trial results indicated no significant difference in the mean values of parameters used to describe the response of concentrations to a step change in generator output rate. Individual trial results indicated a broad range of responses about mean levels even when operating with the same conditions. A novel technique for disregarding much of the instantaneous variation was devised, based on the exponentially weighted average of the measurements. This method proved to be able to maintain chamber concentrations near a desired level and reduce both the total magnitude and number of corrections required to maintain concentrations near a desired level.
NIOSH-Grant; Grants-other; Air-quality-monitoring; Indoor-air-pollution; Control-technology; Ventilation-systems; Indoor-environmental-quality
Civil Engineering University of Vermont RM 226 Votey Bldg Burlington, VT 05405
Final Grant Report
NTIS Accession No.
Department of Civil and Environmental Engineering, College of Engineering and Mathematics, University of Vermont, Burlington, Vermont
University of Vermont & St Agric College, Burlington, Vermont