Diagnostic equipment developed for an International Space Station experiment, the Smoke Aerosol Measurement Experiment (SAME), utilized three measurement devices to determine size properties of the smoke aerosols generated. They consisted of a light-scattering photometer, an ionization chamber from a residential smoke alarm, and a condensation particle counter. The ability to predict the ionization chamber and photometer outputs from aerosol size distribution and concentration information was examined. Using dioctyl phthalate aerosols ranging in mean size from about 0.1 m to 1.0 m, the relative expanded uncertainty of the ionization chamber prediction using total aerosol length was + 12 %, while the relative expanded uncertainty of the photometer prediction was + 33 % using a Mie-scattering model and the aerosol number concentration, size distribution, and refractive index. Smoke was generated from electrically heated silicone, Kapton, Teflon, cotton wick, and dibutyl phthalate samples using the SAME experimental hardware. The smokes were measured with the SAME diagnostic equipment plus additional aerosol instrumentation. Using measured size distributions and particle number concentrations along with estimates of the refractive index, the photometer predictions were within + 25 % for most smokes except Kapton which appears to have an agglomerate structure as determined by electron microscopy.
Proceedings Title: 14th International Conference on Automatic Fire Detection "AUBE '09"
Conference Dates: September 9-11, 2009
Conference Location: Duisburg, -1
Pub Type: Conferences
smoke detection, size distribution, light scattering