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Title: Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests

Abstract

In this paper a new approach to photochemical modeling is investigated and a lagrangian particle model named Photochemical Lagrangian Particle Model (PLPM) is described. Lagrangian particle models are a consolidated tool to deal with the dispersion of pollutants in the atmosphere. Good results have been obtained dealing with inert pollutants. In recent years, a number of pioneering works have shown as Lagrangian models can be of great interest when dealing with photochemistry, provided that special care is given in the reconstruction of chemicals concentration in the atmosphere. Density reconstruction can be performed through the so called ''box counting'' method: an Eulerian grid for chemistry is introduced and density is computed counting particles in each box. In this way one of the main advantages of the Lagrangian approach, the grid independence, is lost. Photochemical reactions are treated in PLPM by means of the complex chemical mechanism SAPRC90 and four density reconstruction methods have been developed, based on the kernel density estimator approach, in order to obtain grid-free accurate concentrations. These methods are all fully grid-free but they differ each other in considering local or global features of the particles distribution, in treating the Cartesian directions separately or together and in beingmore » based on receptors or particles positions in space.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
899438
Report Number(s):
UCRL-JRNL-219202
TRN: US0701963
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Atmospheric Environment, vol. 40, n/a, January 12, 2006, pp. 7770-7785
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHEMISTRY; DISTRIBUTION; KERNELS; LAGRANGIAN FUNCTION; PARTICLE MODELS; PHOTOCHEMICAL REACTIONS; PHOTOCHEMISTRY; POLLUTANTS; SIMULATION

Citation Formats

Monforti, F, Vitali, L, Bellasio, R, and Bianconi, R. Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests. United States: N. p., 2006. Web.
Monforti, F, Vitali, L, Bellasio, R, & Bianconi, R. Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests. United States.
Monforti, F, Vitali, L, Bellasio, R, and Bianconi, R. Tue . "Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests". United States. doi:. https://www.osti.gov/servlets/purl/899438.
@article{osti_899438,
title = {Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests},
author = {Monforti, F and Vitali, L and Bellasio, R and Bianconi, R},
abstractNote = {In this paper a new approach to photochemical modeling is investigated and a lagrangian particle model named Photochemical Lagrangian Particle Model (PLPM) is described. Lagrangian particle models are a consolidated tool to deal with the dispersion of pollutants in the atmosphere. Good results have been obtained dealing with inert pollutants. In recent years, a number of pioneering works have shown as Lagrangian models can be of great interest when dealing with photochemistry, provided that special care is given in the reconstruction of chemicals concentration in the atmosphere. Density reconstruction can be performed through the so called ''box counting'' method: an Eulerian grid for chemistry is introduced and density is computed counting particles in each box. In this way one of the main advantages of the Lagrangian approach, the grid independence, is lost. Photochemical reactions are treated in PLPM by means of the complex chemical mechanism SAPRC90 and four density reconstruction methods have been developed, based on the kernel density estimator approach, in order to obtain grid-free accurate concentrations. These methods are all fully grid-free but they differ each other in considering local or global features of the particles distribution, in treating the Cartesian directions separately or together and in being based on receptors or particles positions in space.},
doi = {},
journal = {Atmospheric Environment, vol. 40, n/a, January 12, 2006, pp. 7770-7785},
number = ,
volume = ,
place = {United States},
year = {Tue Feb 21 00:00:00 EST 2006},
month = {Tue Feb 21 00:00:00 EST 2006}
}
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