AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
A New Portable Dual Smog Chamber Facility with UV Lights for Field Studies
CHRISTOS KALTSONOUDIS, Evangelos Louvaris, Epameinondas Tsiligiannis, Evangelia Kostenidou, Spyros Pandis, University of Patras, Patra, Greece
Abstract Number: 268 Working Group: Instrumentation and Methods
Abstract Field smog chamber experiments using as a starting point ambient air can improve our understanding of the evolution of atmospheric pollutants at timescales longer than those achieved by traditional laboratory experiments. These types of studies can take place under more realistic environmental conditions. Use of two identical smog chambers, with the first being the baseline chamber and the second the perturbation chamber (e.g. addition or removal of pollutants, addition of oxidants, change in the RH etc.) can assist in the interpretation of the results in such inherently complex chemical systems. The differences of the measurements in the two chambers can be used as the basis for the study of the corresponding chemical or physical processes.
In this work a new dual smog chamber system was developed. A set of two identical smog chambers (1.5 m$^3 each) were constructed from Teflon (PTFE) 0.2 micrometer film. The two chambers are pillow-shaped and permanently mounted on metal frames. The relatively small dimensions along with the fixed frames enable the easy and safe transport of the empty chambers without having to disassemble them or remove the sampling ports. The two chambers are surrounded by 60 (36 W each) UV lamps in a hexagonal arrangement (with one side open) yielding a J$_(NO2) of 0.1 min$^(-1). The lamps are mounted on five metal frames creating five sub-structures that can be easily disassembled and transported. Once assembled the UV light support structure has a footprint of 4.5 m in diameter and a height of 2.5 m which can be fully covered or partially uncovered if natural sunlight is required. The system has been evaluated in a series of experiments testing its levels of contamination, similarity of the behavior of the two chambers, wall losses and perturbation experiments of ambient air showing promising results.