Abstract
Auto-ignition is a complex process which is extremely sensitive to boundary conditions such as local temperature, mixture or strain rate and occurs on very short time-scales. Therefore, measurement techniques with high spatio-temporal resolution have to be applied to test cases with well-defined boundary conditions in order to generate high-quality validation data for numerical simulations. In the current paper, the auto-ignition of a transient propane jet-in-hot coflow was studied with high-speed OH* chemiluminescence imaging and high-speed Rayleigh scattering for the simultaneous determination of mixture fraction, mixture temperature and scalar dissipation rate immediately prior to the onset of auto-ignition. A variation of the coflow temperature showed a pronounced temperature dependence of the auto-ignition location and time, and the temperature sensitivity was higher than for a comparable methane test case from the literature. This is explained by the lower sensitivity of propane ignition delay times to the local strain rate in comparison to methane. The Rayleigh measurements however showed that the formation mechanism of auto-ignition kernels is similar for propane and methane. Ignition kernels were found to form upstream of bulges of the inflowing jet at locations with locally low scalar dissipation rate.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
