Single Particle Counting Diagnostic System for Measuring Fine Particulates at High Number Densities in Research and Industrial Applications. Final Report Summarizing Instrument Development, Validation and Operating Instructions

摘要

Optical methods for particle size distribution measurements in practical high temperature environments have achieved feasibility and offer significant advantages over conventional sampling methods. The present report describes a mobile electro-optical system which has been designed for general use in a wide range of research and industrial environments. Specific features of this system include a method of providing in situ alignment and incorporation of an extinction measurement for application to optically thick aerosol flows. The instrument has demonstrated capability for measuring individual particles in the size range 0.25 to 100 microns at number densities up to 10 exp 12 /m exp 3 . In addition to demonstration of the system's wide dynamic range, we show the utility of the in situ alignment method in hot (1100 K) turbulent flows where beam steering can be a problem. As an example of the instrument's application, number and mass frequency distribution measurements of flyash and pulverized coal obtained in an atmospheric combustion exhaust simulator show that the raw pulverized coal contains large numbers of submicron particles similar to the flyash formed after combustion. (ERA citation 09:001143)