Image B was recorded with a high-speed camera at 1000 fps with 1 millisecond exposure time. This image shows some of the fine details of the flame shape, but it is a little dim and blurry. The high-speed camera does a decent job at preventing motion blur by having a short exposure time. But because of this short exposure time, the camera can't collect enough light to capture a detailed image.
Image C shows what a flame looks like when using a 15 microsecond exposure time. To achieve such a short exposure time but retain image detail, we used the fast electro-optical shutter function of the image intensifier. This technique is called gating, and it allows for ultra-short exposure times. During this short exposure time, the image intensifier boosts the intensity of the incoming light to retain image detail.
This unique imaging technology enables experimental investigation of combustion and flame structure. For more information about applications of image intensifier gating for combustion research please have a look at these HiCATT user publications:
Baptiste Déjean, Pierre Berthoumieu and Pierre Gajan, Experimental study on the influence of liquid and air boundary conditions on a planar air-blasted liquid sheet, Part II: prefilming zone length in the International Journal of Multiphase Flow
Shigeru Tachibana, Kinya Saito, Takeshi Yamamoto, Mitsumasa Makida, Tomoaki Kitano and Ryoichi Kurose, Experimental and numerical investigation of thermo-acoustic instability in a liquid-fuel aero-engine combustor at elevated pressure: Validity of large-eddy simulation of spray combustion in Combustion and Flame
Min Jung Lee, Moon Soo Cho and Nam Il Kim, Characteristics of opposed flow partially premixed flames in mesoscale channels at low strain rates in Proceedings of the Combustion Institute
For a full overview of HiCATT user publications, please visit our HiCATT User Publications page.