Modeling light scattering from diesel soot particles

Journal Article · Tue Jul 16 04:00:00 EDT 2002 · Journal of Applied Optics

OSTI ID:835984

Hull, Patricia ^[1]; Shepherd, Ian; Hunt, Arlon

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1. LBNL Library

The Mie model is widely used to analyze light scattering from particulate aerosols. The Diesel Particle Scatterometer (DPS), for example, determines the size and optical properties of diesel exhaust particles that are characterized by measuring three angle-dependent elements of the Mueller scattering matrix. These elements are then fitted using Mie calculations with a Levenburg-Marquardt optimization program. This approach has achieved good fits for most experimental data. However, in many cases, the predicted real and imaginary parts of the index of refraction were less than that for solid carbon. To understand this result and explain the experimental data, we present an assessment of the Mie model by use of a light scattering model based on the coupled dipole approximation. The results indicate that the Mie calculation can be used to determine the largest dimension of irregularly shaped particles at sizes characteristic of Diesel soot and, for particles of known refractive index, tables can be constructed to determine the average porosity of the particles from the predicted index of refraction.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE. Assistant Secretary for Energy Efficiency and Renewable Energy, Director. Office of Science. Office of Basic Energy Sciences. Chemical Sciences Division (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 835984
• Report Number(s): LBNL--51105
• Journal Information: Journal of Applied Optics, Journal Name: Journal of Applied Optics Journal Issue: 17 Vol. 43
• Country of Publication: United States
• Language: English

Related Subjects

29 ENERGY PLANNING, POLICY, AND ECONOMY
AEROSOLS
CARBON
DIMENSIONS
DIPOLES
LIGHT SCATTERING
OPTICAL PROPERTIES
OPTIMIZATION
PARTICULATES
POROSITY
REFRACTIVE INDEX
SCATTERING
SIMULATION
SOOT