Simultaneous measurement of temperature and chemicalspecies concentrations with a holographic interferometer and infrared absorption

Abstract

What is believed to be a new technique that allows for the simultaneous measurement of 2D temperature and chemical species concentration profiles with high spatial resolution and fast time response was developed and tested successfully by measuring a thin layer of fuel vapor created over a volatile fuel surface. Normal propanol was placed in an open-top rectangular container, and n-propanol fuel vapor was formed over the propanol surface in a quiescent laboratory environment. An IR beam with a wavelength of 8-13 mum emitted from a heated plate and a He-Ne laser beam with a wavelength of 632 nm were combined and passed through the n-propanol vapor layer, and both beams were absorbed by the vapor layer. The absorption of the IR beam was recorded by an IR camera, and the He-Ne laser was used to form a holographic interferogram. Two-dimensional temperature and propanol vapor concentration profiles were, respectively, determined by the IR absorption and the fringe pattern associated with the holographic interferogram. This new measurement technique is a significant improvement over the dual wavelength holographic interferometry that has been used previously to measure temperature and fuel concentration, and it is ready for application under different types of fire and flame conditions.

Measurement of Microclimate within Clothing Using the Combination Technique of Infrared Ray Absorption Method And Holographic Interferometry

“…This measurement technique is characterized by combining infrared ray (IR) and absorption method with real time holographic interferometry (HI). The principles [2][3][4][5][6][7] of this measurement technique depend on the attenuation of radiation intensity of IR due to the vapor absorption and the variation of refractive index of phase object due to the changes of temperature and concentration. The concentration value can be obtained at any local point from Lambert-Beer's law through IR absorption method.…”

Holographic Interferometer for the Study of Phase Media, Which Has Four Output Channels of Different Sensitivity

“…To date, many methods have been proposed for studying the characteristics of phase media, such as, for example, the distribution of temperature fields [23][24][25]. However, the measurement methods proposed in these works are based on the methods of holographic interferometry with a single output channel, which limits their ability to measure in complex phase media, with a continuously changing pattern of temperature distribution.…”

Combined Error Elimination for Three Dimensional Thermal Images Using Hybrid Digital Holography

“…IR (infrared) digital holography is one of the techniques to achieve the thermal information of the object surface in reconstructed wave field [1]. Typically, IR digital holography has lower resolution than the general digital holography that is used with a visible laser [2,3].…”