Second Law Analysis of Constant Temperature Diesel Combustion

Conference · Sun Jan 01 04:00:00 EST 2006

OSTI ID:1003660

Druecke, Dr. Ben ^[1]; Foster, Prof. Dave ^[1]; Klein, Prof. Sandy ^[1]; Daw, C Stuart ^[2]; Chakravarthy, Veerathu K ^[2]; Graves, Ronald L ^[2]

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1. University of Wisconsin
2. ORNL

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.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center
• Sponsoring Organization: EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1003660
• Country of Publication: United States
• Language: English

Related Subjects

combustion
energy efficiency
second law