Experimental and numerical investigation on spark ignition of linearly-arranged non-premixed swirling burners

The ignition characteristics of a non-premixed multiple-burner linear combustion chamber was investigated experimentally and numerically, focusing on the determination of the mechanisms driving flame propagation from burner to burner. For different inter-burner spacings, overall equivalence ratios and bulk velocities, measurements of the velocity field and the mixture fraction distribution have been performed, respectively, with laser doppler anemometry and planar laser-induced fluorescence of acetone in the un-ignited flow. It was shown that in every individual burner, gas mixes with air within a central recirculation zone (CRZ) where the mixture is flammable except in the axial central rich gas jet and the annular air jet. Flammable mixture from the CRZ is extracted by the annular jet and this results in the existence of bridges of positive flammability factor in the inter-burner region. These bridges allow flame fragments to travel from the CRZ of the ignited burner to the CRZ of the adjacent unignited one, leading to burner-to-burner flame propagation. The ignition probability that sparking within a burner results in ignition of the adjacent one was obtained by performing many separate ignition trials with a laser spark. Ignition probability contours were also computed using a previously developed stochastic low-order ignition model and a large eddy simulation (LES) time-averaged solution of the cold flow. The quantification of the probability a flame kernel leads to burner ignition explained the differences existing between experimental results and the model. The results presented in this article extend our understanding of the mechanisms underlying the global ignition behavior of non-premixed annular combustion chambers.The authors gratefully acknowledge financial assistance from the EPSRC

La Charente

10 février 18851885/02/10 (A14,N4634)-1885/02/10.Appartient à l’ensemble documentaire : PoitouCh

Additional file 2: of The genome-wide transcription response to telomerase deficiency in the thermotolerant yeast Hansenula polymorpha DL-1

Supplementary tables presenting the data on differential expression of H. polymorpha DL-1 genes. Table S1 Differential expression of H. polymorpha DL-1 genes classified into KEGG groups. Table S2. Expression levels of H. polymorpha DL-1 genes related to telomere maintenance. Table S3. Expression levels of H. polymorpha DL-1 genes relevant to autophagy. Table S4. Expression levels of H. polymorpha DL-1 genes relevant to cell architecture and intracellular traffic. Table S5. Expression levels of H. polymorpha DL-1 genes related to DNA damage checkpoint signaling, DNA replication and repair. Table S6. Expression levels of H. polymorpha DL-1 antioxidant system and heat shock genes. Table S7. Expression levels of H. polymorpha DL-1 genes involved in glycolysis, gluconeogensis and pyruvate metabolism. Table S8. Expression levels of H. polymorpha DL-1 pentose phosphate pathway genes. Table S9. Expression levels of H. polymorpha DL-1 tricarboxylic acids cycle genes. Table S10. Expression levels of H. polymorpha DL-1 genes encoding cytochrom c oxidase and related proteins. Table S11. Expression levels of H. polymorpha DL-1 genes encoding the NADH dehodrogenase subunits. Table S12. Expression levels of H. polymorpha DL-1 genes encoding the ATP synthase subunits. Table S13. Expression of homologs of telomerase deletion signature genes of Saccharomyces cerevisiae described in Nautiyal et al. (2002). (PDF 418 kb