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Estimations of Photopheresis and Thermophoresis Impacts on Soot Particle Velocity
Published
Author(s)
Emma Veley, Amy Mensch, Ryan Falkenstein-Smith, Thomas Cleary
Abstract
The dissemination of soot particles onto surfaces in a compartment fire is affected by local radiation and temperature gradients. Subsequently, any deposition model must account for the influence of photopheresis and thermophoresis on the deposition process. The research completed for this study used a large eddy simulation to examine the photophoretic and thermophoretic velocities associated with experiments of deposition soot onto aluminum targets attached to a gypsum board. An additional conduction computational simulation was performed to determine the magnitude of the temperature difference between the target and the substrate, which could cause differences in the local temperature gradients and therefore the soot deposition. Estimations from the results of the large eddy simulation indicated that the photophoretic velocity is several orders of magnitude less than the deposition velocity and that the thermophoretic velocity is only one order of magnitude less than the deposition velocity. The conduction simulations indicated a small temperature difference between the target and the substrate, which would result in insignificant changes to the thermophoretic velocity and therefore minimal differences in the deposition on the two materials.
Proceedings Title
Eastern States Section - The Combustion Institute
Conference Dates
March 10-13, 2024
Conference Location
Athens, GA, US
Conference Title
Eastern States Section - The Combustion Institute Spring Technical Meeting
Veley, E.
, Mensch, A.
, Falkenstein-Smith, R.
and Cleary, T.
(2024),
Estimations of Photopheresis and Thermophoresis Impacts on Soot Particle Velocity, Eastern States Section - The Combustion Institute, Athens, GA, US, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957450
(Accessed October 9, 2025)