Optical particle sizing for in situ measurements Part 2

Area of Science:

• Aerosol Science and Engineering
• Particle Characterization
• Combustion Diagnostics

Background:

• Accurate in situ particle sizing is crucial for understanding aerosol behavior and impacts.
• Previous work (Part 1) detailed the in situ particle sizing counter's design and data processing.
• Experimental validation under diverse conditions is necessary to establish instrument reliability.

Purpose of the Study:

• To experimentally validate the performance of an in situ particle sizing counter.
• To assess the counter's accuracy in measuring particle size distributions at ambient and combustion temperatures.
• To evaluate the instrument's potential for analyzing challenging aerosol types.

Main Methods:

• Utilized well-characterized monodispersions for ambient temperature calibration and testing.
• Employed silica beads (1-30 microm) injected into a burner for combustion condition measurements.
• Applied the unfolding technique from Part 1 to analyze amplitude data and determine size distributions.

Main Results:

• Ambient measurements accurately reproduced the known number density vs. particle diameter of input monodispersions.
• Combustion measurements satisfactorily matched the input size distribution of injected glass bead polydispersions.
• Error propagation analysis of the inversion scheme was performed.

Conclusions:

• The in situ particle sizing counter demonstrates reliable performance across ambient and combustion environments.
• The instrument shows promise for applications involving high number density, absorbing, and irregular aerosols.
• Successful validation supports the counter's utility in various scientific and industrial aerosol studies.