Quantitative characterization of vapour adsorption on solid surfaces and estimation of emissivity of solids using infrared thermography
نویسنده
چکیده
The process of adsorption of water-vapour molecules on uneven (irregular) surfaces of some solid materials at room temperature is registered by infrared camera. The pronounced "thermal flame" ("thermal fire") phenomenon developing on the samples’ surfaces is exhibited and quantitatively represented. This thermal effect ranged within an order of magnitude. 3-μm-wavelength emissivities of different fabrics are obtained experimentally with the presented non-standard reflection-based method that needs for a narrow-spectral-range infrared camera. An analytical relationship between the amount of adsorbate and the measurable excess of adsorbent temperature is derived. Exclusively high sensitivity of the FPA-based infrared method as applied to the examination of initial stages of adsorption of gaseous molecules on solid surfaces is discovered. It is shown that the method makes it possible to control an incipient molecular film of 1/300-monolayer effective thickness precipitated on the exposed surface of a bulky material and of 1/600-monolayer thickness in the case of the adsorption on a thin-film adsorbent (with a double-faced surface).
منابع مشابه
Experimental Detection of Composite Delamination Damage based on Ultrasonic Infrared Thermography
An experimental setup is designed to detect composite delamination damage based on ultrasonic infrared thermography. The ultrasonic infrared thermography system is composed by ultrasonic excitation system, infrared thermal imager and data acquisition system and two damaged composite plate specimens are produced in the experiment. The image processing methods including thresholding, filters, edg...
متن کاملMeasuring the temperature of high-luminous exitance surfaces with infrared thermography in LED applications
Recently, light-emitting diode (LED) lighting systems have become popular due to their increased system performance. LED lighting system performance is affected by heat; therefore, it is important to know the temperature of a target surface or bulk medium in the LED system. In-situ temperature measurements of a surface or bulk medium using intrusive methods cause measurement errors. Typically, ...
متن کاملThe Use of Multispectral Infrared Thermography in Re-entry Vehicles
This paper describes the design of a second generation infrared thermography system for use in a re-entry vehicle. Due to the large number of contaminants such as hydrazine and partial oxidation of the surfaces the simultaneous observation of temperature and emissivity must be performed. To this end a multispectral concept was validated in laboratory tests and implemented in the design.
متن کاملRepresentation of Adsorption Data for the Case of Energetically Heterogeneous Solid Surfaces Using Artificial Neural Network
متن کامل
Experimental methodology for characterizing flame emissivity of small scale forest fires using infrared thermography techniques
An experimental methodology based on thermography techniques has been developed and implemented with the aim of finding emissivity values of forest fuel flames. In this paper, previous works by different authors are discussed and theoretical fundamentals of heat transfer by radiation and of infrared thermography on which experimental method relies are briefly described. Then, designed methodolo...
متن کامل