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Flow visualization of heated CO2 gas using thermal imaging



Joseph P. Rice, Howard W. Yoon, M H. Brenner, N R. Briggs, J G. Gillen


Walk-through portal detection systems are being developed to screen passengers for the presence of explosives in support of homeland security. These portals utilize a series of air-jets to remove the explosive particles for detection using ion mobility spectrometry. In this work, we describe the use of a thermal imager to visualize the flow from the nozzles with heated, pure CO2 gas for enhanced emission. The thermal imaging is performed using an LN2-cooled, InSb focal-plane array with a germanium lens. Since CO2 gas at 300 K has a strong absorption centered at 4.3 mm which is isolated from other absorbing gases, a spectral filter centered at 4.4425 mm with a full-width half maximum bandwidth of 0.18 mm was used to detect the CO2 emission. To increase the radiance from the gas, pure, heated CO2 was ejected from the nozzle. The concentration of CO2 in standard atmosphere is
Proceedings of SPIE


blackbody calibration, carbon dioxide, flow visualization, non-uniformity correction, thermal imaging


Rice, J. , Yoon, H. , Brenner, M. , Briggs, N. and Gillen, J. (2006), Flow visualization of heated CO2 gas using thermal imaging, Proceedings of SPIE (Accessed May 29, 2024)


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Created January 1, 2006, Updated February 17, 2017