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Title: Second Law Analysis of Constant Temperature Diesel Combustion

Abstract

The results from a second law analysis of a constant temperature diesel combustion process are presented and show that this process is not significantly more reversible than conventional combustion. In addition to quantifying the total availability destruction in combustion, the magnitudes of the combustion irreversibilities attributable to each irreversible subprocess (mixing, oxidation and internal heat transfer) were determined. The primary contributor to combustion irreversibilities is the thermal interaction of reacting and non-reacting species during the oxidation and internal thermal energy transfer subprocesses. Increasing combustion temperature significantly decreases availability destruction by making the oxidation and internal thermal energy transfer processes more reversible. While increasing combustion temperature decreases combustion irreversibility, it also results in an increase in exhaust temperature. A tradeoff exists between large availability destruction at low combustion temperatures and large amounts of availability discarded in the exhaust at high combustion temperatures. The optimum amount of work was found to occur for a combustion temperature of approximately 1600 K.

Authors:
 [1];  [1];  [1];  [2];  [2];  [2]
  1. University of Wisconsin
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center (FEERC)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1003660
DOE Contract Number:
AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: 2006 Spring Technical Meeting of the Central States Section of the Combustion Institute, Cleveland, OH, USA, 20060521, 20060523
Country of Publication:
United States
Language:
English
Subject:
combustion; energy efficiency; second law

Citation Formats

Druecke, Dr. Ben, Foster, Prof. Dave, Klein, Prof. Sandy, Daw, C Stuart, Chakravarthy, Veerathu K, and Graves, Ronald L. Second Law Analysis of Constant Temperature Diesel Combustion. United States: N. p., 2006. Web.
Druecke, Dr. Ben, Foster, Prof. Dave, Klein, Prof. Sandy, Daw, C Stuart, Chakravarthy, Veerathu K, & Graves, Ronald L. Second Law Analysis of Constant Temperature Diesel Combustion. United States.
Druecke, Dr. Ben, Foster, Prof. Dave, Klein, Prof. Sandy, Daw, C Stuart, Chakravarthy, Veerathu K, and Graves, Ronald L. Sun . "Second Law Analysis of Constant Temperature Diesel Combustion". United States. doi:.
@article{osti_1003660,
title = {Second Law Analysis of Constant Temperature Diesel Combustion},
author = {Druecke, Dr. Ben and Foster, Prof. Dave and Klein, Prof. Sandy and Daw, C Stuart and Chakravarthy, Veerathu K and Graves, Ronald L},
abstractNote = {The results from a second law analysis of a constant temperature diesel combustion process are presented and show that this process is not significantly more reversible than conventional combustion. In addition to quantifying the total availability destruction in combustion, the magnitudes of the combustion irreversibilities attributable to each irreversible subprocess (mixing, oxidation and internal heat transfer) were determined. The primary contributor to combustion irreversibilities is the thermal interaction of reacting and non-reacting species during the oxidation and internal thermal energy transfer subprocesses. Increasing combustion temperature significantly decreases availability destruction by making the oxidation and internal thermal energy transfer processes more reversible. While increasing combustion temperature decreases combustion irreversibility, it also results in an increase in exhaust temperature. A tradeoff exists between large availability destruction at low combustion temperatures and large amounts of availability discarded in the exhaust at high combustion temperatures. The optimum amount of work was found to occur for a combustion temperature of approximately 1600 K.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Conference:
Other availability
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