Kihun Moon, Richard Martin, Bruno Schuermans, Nicolas Noiray
{"title":"Transfer functions of lean fully- and technically-premixed jet-stabilized turbulent hydrogen flames","authors":"Kihun Moon, Richard Martin, Bruno Schuermans, Nicolas Noiray","doi":"10.1016/j.proci.2024.105256","DOIUrl":null,"url":null,"abstract":"Understanding the response of multi-jet turbulent hydrogen-air flames to acoustic forcing is key for the development of future carbon-neutral gas turbine combustors. In this paper, we present flame transfer functions (FTFs) deduced from burner and flame transfer matrices obtained with acoustic measurements for fully-premixed (FP) and technically-premixed (TP) conditions, in conjunction with their analytical models. The matrix burner used in this study produces an array of sixteen turbulent lean hydrogen-air jet flames. Its acoustic transfer matrix is analytically modeled, with experimental validation. It exhibits a significant frequency dependence due to the non-compactness of the burner with respect to the acoustic wavelength considered. Our results show that the conical jet-stabilized flames have a typical low-pass filter behavior in the FP case, while in the TP case, they exhibit a frequency dependent gain modulation originating from the combination of mass flow and equivalence ratio oscillations. Using distributed time delay (DTD) models, we identify the dominant disturbances controlling the FTF data measured at different equivalence ratios and bulk velocities, and show that they can be well collapsed by using the associated Strouhal numbers. To unravel the smooth transition of FTF between the FP and TP cases, staging of the fuel is employed in the present study. We demonstrate that the features of the FTFs for staging conditions ranging from FP to TP are strongly correlated with the fuel staging ratio and can be well reproduced by a linear superposition of the FTFs of the pure FP and TP cases.","PeriodicalId":408,"journal":{"name":"Proceedings of the Combustion Institute","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Combustion Institute","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.proci.2024.105256","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
Understanding the response of multi-jet turbulent hydrogen-air flames to acoustic forcing is key for the development of future carbon-neutral gas turbine combustors. In this paper, we present flame transfer functions (FTFs) deduced from burner and flame transfer matrices obtained with acoustic measurements for fully-premixed (FP) and technically-premixed (TP) conditions, in conjunction with their analytical models. The matrix burner used in this study produces an array of sixteen turbulent lean hydrogen-air jet flames. Its acoustic transfer matrix is analytically modeled, with experimental validation. It exhibits a significant frequency dependence due to the non-compactness of the burner with respect to the acoustic wavelength considered. Our results show that the conical jet-stabilized flames have a typical low-pass filter behavior in the FP case, while in the TP case, they exhibit a frequency dependent gain modulation originating from the combination of mass flow and equivalence ratio oscillations. Using distributed time delay (DTD) models, we identify the dominant disturbances controlling the FTF data measured at different equivalence ratios and bulk velocities, and show that they can be well collapsed by using the associated Strouhal numbers. To unravel the smooth transition of FTF between the FP and TP cases, staging of the fuel is employed in the present study. We demonstrate that the features of the FTFs for staging conditions ranging from FP to TP are strongly correlated with the fuel staging ratio and can be well reproduced by a linear superposition of the FTFs of the pure FP and TP cases.
期刊介绍:
The Proceedings of the Combustion Institute contains forefront contributions in fundamentals and applications of combustion science. For more than 50 years, the Combustion Institute has served as the peak international society for dissemination of scientific and technical research in the combustion field. In addition to author submissions, the Proceedings of the Combustion Institute includes the Institute''s prestigious invited strategic and topical reviews that represent indispensable resources for emergent research in the field. All papers are subjected to rigorous peer review.
Research papers and invited topical reviews; Reaction Kinetics; Soot, PAH, and other large molecules; Diagnostics; Laminar Flames; Turbulent Flames; Heterogeneous Combustion; Spray and Droplet Combustion; Detonations, Explosions & Supersonic Combustion; Fire Research; Stationary Combustion Systems; IC Engine and Gas Turbine Combustion; New Technology Concepts
The electronic version of Proceedings of the Combustion Institute contains supplemental material such as reaction mechanisms, illustrating movies, and other data.