A study on the effects of air preheat on the combustion and heat transfer characteristics of Bunsen flames

H. S. Zhen, J. Miao, Chun Wah Leung, Chun Shun Cheung, Z. H. Huang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

10 Citations (Scopus)

Abstract

Flue Gas Recirculation (FGR) has been an effective technique for energy saving for large-scale industrial furnaces. Against this background, an experimental study was conducted to investigate the thermal, emission and heating performance of CH4-H2/air flames in terms of their dependence on both dilution effect (CO2and N2) and preheat effect (initial reactant temperature from 20 °C to 100 °C). Testing of flame stability showed detrimental and favorable effects of dilution and preheat, respectively. Examination of flame height showed that under constant Re and Ф, the reaction cone is shorter at higher initial reactant temperature, indicative of enhanced burning velocity caused by preheat. Emission of CO and NOxwas monotonically increased as the result of higher flame temperature due to preheat. The key question whether flame heating performance can be promoted or not is answered by detailed analysis of the radial heat flux configurations. The data reveals that the combined effects of dilution and preheat indeed induce higher heat transfer rate, thus theoretical evidence is provided for feasibility of adoption of FGR in domestic cookers.
Original languageEnglish
Pages (from-to)50-58
Number of pages9
JournalFuel
Volume184
DOIs
Publication statusPublished - 15 Nov 2016

Keywords

  • Air preheat
  • Flame impingement heat transfer
  • Flue gas recirculation

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Organic Chemistry

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