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Title: Soot and Spectral Radiation Modeling in ECN Spray A and in Engines

Abstract

The amount of soot formed in a turbulent combustion system is determined by a complex system of coupled nonlinear chemical and physical processes. Different physical subprocesses can dominate, depending on the hydrodynamic and thermochemical environments. Similarly, the relative importance of reabsorption, spectral radiation properties, and molecular gas radiation versus soot radiation varies with thermochemical conditions, and in ways that are difficult to predict for the highly nonhomogeneous in-cylinder mixtures in engines. Here it is shown that transport and mixing play relatively more important roles as rate-determining processes in soot formation at engine-relevant conditions. It is also shown that molecular gas radiation and spectral radiation properties are important for engine-relevant conditions.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [3];  [3]
  1. Pennsylvania State Univ., University Park, PA (United States)
  2. Marquette University (United States)
  3. University of California Merced (United States)
Publication Date:
Research Org.:
The Pennsylvania State University
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
1354682
DOE Contract Number:
EE0007278
Resource Type:
Conference
Resource Relation:
Conference: International Multidimensional Engine Modeling User's Group Meeting at the SAE Congress, Detroit, MI, 3 April 2017
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS

Citation Formats

Haworth, Daniel C, Ferreyro-Fernandez, Sebastian, Paul, Chandan, Sircar, Arpan, Imren, Abdurrahman, Roy, Somesh P, Modest, Michael F, and Ge, Wenjun. Soot and Spectral Radiation Modeling in ECN Spray A and in Engines. United States: N. p., 2017. Web.
Haworth, Daniel C, Ferreyro-Fernandez, Sebastian, Paul, Chandan, Sircar, Arpan, Imren, Abdurrahman, Roy, Somesh P, Modest, Michael F, & Ge, Wenjun. Soot and Spectral Radiation Modeling in ECN Spray A and in Engines. United States.
Haworth, Daniel C, Ferreyro-Fernandez, Sebastian, Paul, Chandan, Sircar, Arpan, Imren, Abdurrahman, Roy, Somesh P, Modest, Michael F, and Ge, Wenjun. Mon . "Soot and Spectral Radiation Modeling in ECN Spray A and in Engines". United States. doi:. https://www.osti.gov/servlets/purl/1354682.
@article{osti_1354682,
title = {Soot and Spectral Radiation Modeling in ECN Spray A and in Engines},
author = {Haworth, Daniel C and Ferreyro-Fernandez, Sebastian and Paul, Chandan and Sircar, Arpan and Imren, Abdurrahman and Roy, Somesh P and Modest, Michael F and Ge, Wenjun},
abstractNote = {The amount of soot formed in a turbulent combustion system is determined by a complex system of coupled nonlinear chemical and physical processes. Different physical subprocesses can dominate, depending on the hydrodynamic and thermochemical environments. Similarly, the relative importance of reabsorption, spectral radiation properties, and molecular gas radiation versus soot radiation varies with thermochemical conditions, and in ways that are difficult to predict for the highly nonhomogeneous in-cylinder mixtures in engines. Here it is shown that transport and mixing play relatively more important roles as rate-determining processes in soot formation at engine-relevant conditions. It is also shown that molecular gas radiation and spectral radiation properties are important for engine-relevant conditions.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 03 00:00:00 EDT 2017},
month = {Mon Apr 03 00:00:00 EDT 2017}
}

Conference:
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  • Simulations are performed of a transient high-pressure turbulent n-dodecane spray flame under engine-relevant conditions. An unsteady RANS formulation is used, with detailed chemistry, a semi-empirical two-equation soot model, and a particle-based transported composition probability density function (PDF) method to account for unresolved turbulent fluctuations in composition and temperature. Results from the PDF model are compared with those from a locally well-stirred reactor (WSR) model to quantify the effects of turbulence-chemistry-soot interactions. Computed liquid and vapor penetration versus time, ignition delay, and flame lift-off height are in good agreement with experiment, and relatively small differences are seen between the WSR andmore » PDF models for these global quantities. Computed soot levels and spatial soot distributions from the WSR and PDF models show large differences, with PDF results being in better agreement with experimental measurements. An uncoupled photon Monte Carlo method with line-by-line spectral resolution is used to compute the spectral intensity distribution of the radiation leaving the flame. This provides new insight into the relative importance of molecular gas radiation versus soot radiation, and the importance of turbulent fluctuations on radiative heat transfer.« less
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