Determination of the temperature field using liquid crystal thermography and analysis of two-phase flow structures in research on boiling heat transfer in a minichannel

• Autorzy: Piasecka M.
• Języki publikacji: EN

Abstrakty

EN

The paper presents the application of liquid crystal thermography for temperature determination and visualisation of two phase flow images on the studied surface. Properties and applications of thermochromic liquid crystals are discussed. Liquid crystals were applied for two-dimensional detection of the temperature of the heating foil forming one of the surfaces of the minichannel along which the cooling liquid flowed. The heat flux supplied to the heating surface was altered in the investigation and it was accompanied by a change in the color distribution on the surface. The accuracy of temperature measurements on the surface with liquid crystal thermography is estimated. The method of visualisation of two-phase flow structures is described. The analysis of monochrome images of flow structures was employed to calculate the void fraction for some cross-sections. The flow structure photos were processed using Corel graphics software and binarized. The analysis of phase volumes employed Techsystem Globe software. The measurement error of void fraction is estimated.

Słowa kluczowe

EN

temperature measurement; liquid crystal thermography; measurement accuracy; void fraction

• Wydawca: Komitet Metrologii i Aparatury Naukowej PAN
• Czasopismo: Metrology and Measurement Systems
• Rocznik: 2013
• Tom: Vol. 20, nr 2
• Strony: 205--216
• Opis fizyczny: Bibliogr. 19 poz., rys., wykr.

Twórcy

autor

Piasecka M.

• Kielce University of Technology, Department of Mechanics, Al. 1000-lecia P.P. 7, 25-314 Kielce, Poland

Bibliografia

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Uwagi

EN

The research has been financially supported by the Polish Ministry of Science and Higher Education, Grant No. N N512 354037 for the years 2009-2013.