面向空间受限燃烧场碳烟浓度测量的双色-沙姆激光诱导炽光技术研究OA

To address the need for measuring soot concentration distributions in complex and spatially constrained combustion flow fields,such as the outlet of aero-engine combustors,this study developed the Two-color-Scheimpflug Laser-Induced Incandescence(2C-Scheimpflug LII)technique and a corresponding measurement system,which obtains soot volume fraction distribution images by employing an oblique imaging method.The technique and measurement system validation experiments were first conducted under specific conditions using three typical ethylene/air flames(McKenna,Gülder,and Santoro).Comparisons with measurement results obtained by other researchers under the same conditions demonstrate the feasibility of the 2C-Scheimpflug LII system.The test results in standard flames show that the lower detection limit of soot volume fraction measurements of our system is approximately 2.0×10-9.Further,the 2C-Scheimpflug LII technique was applied to measure the spatial distribution of soot volume fractions at the transverse cross-section of the outlet and the longitudinal section of a single-sector,dual-swirler aero-engine model combustor.The preliminary results show that the soot volume fraction distribution at the combustor outlet exhibits high instantaneous variability and randomness,while within the combustor,the soot volume fraction displays a V-shaped distribution.