Autoignition of Dimethyl Ether and Air in an Optical Flow-Reactor

Summary, in English

Autoignition of dimethyl ether in air was studied in a turbulent flow-reactor with optical access, at conditions relevant to micro gas turbine combustors. The ignition process was visualized using OH*-chemiluminescence imaging, showing the formation of multiple autoignition kernels along the central axis of the reactor. Ignition delays in the range of tau = 112-310 ms were measured at temperatures of T = 739-902 K, pressures of P = 0.2-0.4 MPa, equivalence ratios of phi = 0.225-0.675, and initial flow velocities of U-i = 8-46 m/s. The effect of adding nitrogen to the reactants as a diluent was investigated for mole fractions of additional nitrogen ranging from 0 < X-N2 < 0.1. The experimental ignition delays were compared with homogeneous gas-phase chemical kinetic modeling. Comparison between the modeling and experiments showed significant discrepancies, but agreement was improved when heat transfer in the reactor was taken into account in the modeling.

• Author: Alessandro Schönborn; Parisa Sayad; Alexander Konnov; Jens Klingmann
• Department/s: Thermal Power Engineering; Combustion Physics
• Publishing year: 2014
• Language: English
• Pages: 4130-4138
• Publication/Series: Energy & Fuels
• Volume: 28
• Issue: 6
• Links: http://dx.doi.org/10.1021/ef402476r
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Atom and Molecular Physics and Optics; Energy Engineering
• Status: Published
• ISBN/ISSN/Other: ISSN: 0887-0624