Finding a common ground for RCM experiments. Part B: Benchmark study on ethanol ignition

Combustion and Flame, vol. 262, pp. 113338

Abstract

Rapid compression machines (RCMs) are widely used to investigate gas phase reaction kinetics of various kind of fuels at application relevant conditions. In principle, the operation of an RCM is based on the idea of compressing a homogenous pre-mixed fuel-air mixture by a piston. Usually creviced pistons ensure a homogenous adiabatic core in the center of the reaction chamber which permits the assumption of an isentropic relation between the measured pressure and gas temperature. Despite the ideal core gas compression, non-ideal effects such as heat loss, differences in the compression behavior, and ultimately non-standardized design and operation of rapid compression machines lead to different experimental results in different facilities at nominally the same end of compression conditions. In this study ignition delay times of ethanol are investigated at four different conditions in five independent RCMs. As expected, the raw results of the different facilities indeed show notable differences at the same end of compression conditions. However, according to the adiabatic core hypothesis the agreement between kinetic simulations and experiments should be consistent for all facilities provided that the facility effects are correctly accounted for. To elaborate upon this hypothesis, a kinetic mechanism is optimized to reflect the experimental results of all facilities. In the end, the optimized mechanism predicts all experimental data within the expected uncertainty. This confirms the reliability of RCM experiments for kinetic investigations and the validity of the effective volume approach in simulating RCM data.

Authors 10

1. René Daniel Büttgen Aachen Chair of High Pressure Gas Dynamics Shock Wave Laboratory

   RWTH Aachen University

   Affiliation as printed

   Chair of High Pressure Gas Dynamics, Shock Wave Laboratory, RWTH Aachen University, Aachen 52056, Germany

2. Matthias Preußker Aachen Chair of High Pressure Gas Dynamics Shock Wave Laboratory

   RWTH Aachen University

   Affiliation as printed

   Chair of High Pressure Gas Dynamics, Shock Wave Laboratory, RWTH Aachen University, Aachen 52056, Germany

3. S. Scott Goldsborough

   Argonne National Laboratory

   Affiliation as printed

   Transportation and Power Systems Division, Argonne National Laboratory, Lemont, IL 60439, USA

4. Aamir Farooq

   King Abdullah University of Science and Technology

   Affiliation as printed

   Clean Combustion Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia

5. Hwasup Song

   Centre National de la Recherche Scientifique · Université de Lille · PhysicoChimie des Processus de Combustion et de l'Atmosphère

   Affiliation as printed

   Physicochimie des Processus de Combustion et de l'Atmosphère, University of Lille, CNRS, UMR 8522 - PC2A, Lille F-59000, France

6. Yann Fenard

   Centre National de la Recherche Scientifique · Université de Lille · PhysicoChimie des Processus de Combustion et de l'Atmosphère

   Affiliation as printed

   Physicochimie des Processus de Combustion et de l'Atmosphère, University of Lille, CNRS, UMR 8522 - PC2A, Lille F-59000, France

7. Guillaume Vanhove

   Centre National de la Recherche Scientifique · Université de Lille · PhysicoChimie des Processus de Combustion et de l'Atmosphère

   Affiliation as printed

   Physicochimie des Processus de Combustion et de l'Atmosphère, University of Lille, CNRS, UMR 8522 - PC2A, Lille F-59000, France

8. A. Abd El-Sabor Mohamed

   Ollscoil na Gaillimhe – University of Galway · SFI Research Centre for Energy, Climate and Marine

   Affiliation as printed

   Combustion Chemistry Centre, School of Biological and Chemical Sciences, Ryan Institute, MaREI, University of Galway, Galway, Ireland

9. Henry J. Curran

   Ollscoil na Gaillimhe – University of Galway · SFI Research Centre for Energy, Climate and Marine

   Affiliation as printed

   Combustion Chemistry Centre, School of Biological and Chemical Sciences, Ryan Institute, MaREI, University of Galway, Galway, Ireland

10. Karl Alexander Heufer corresponding Aachen Chair of High Pressure Gas Dynamics Shock Wave Laboratory

    RWTH Aachen University

    Affiliation as printed

    Chair of High Pressure Gas Dynamics, Shock Wave Laboratory, RWTH Aachen University, Aachen 52056, Germany