Thermochromic liquid crystals applied for heat transfer research

• Autorzy: Stasiek J. A. , Kowalewski T. A.
• Języki publikacji: EN

Abstrakty

EN

In recent years thermochromic liquid crystals (TLC) have been successfully used in non-intrusive heat transfer and fluid mechanic studies. Thin coatings of TLC's at surfaces are utilised to obtain detailed heat transfer data of steady or transient process. Application of TLC traces allows instantaneous measurement of temperature and velocity fields for two-dimensional cross-section of flow. Computerised flow visualisation techniques allow automatic quantification of temperature of the analysed surface or the visualised flow cross-section. Here, we describe our experience in applying the method to selected problems studied in our laboratory. They include modelling of flow configurations in the differentially heated inclined cavity with vertical temperature gradient simulating up-slope flow as well as thermal convention under freezinf surface. The main aim of these experimental models is to generate reliable experimental database on velocity and temperature fields for specific flow. The methods are based on computerised true-colour analysis of digital images for temperature measurements and modified particle image velocimetry and thermometry (PIVT) used to obtain the flow field velocity.

Słowa kluczowe

EN

temperature measurements; liquid crystals thermography; particle image velocimetry; particle image thermometry

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2002
• Tom: Vol. 10, No. 1
• Strony: 1--10
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Stasiek J. A.

autor

Kowalewski T. A.

• Faculty of Mechanical Engineering, Technical University of Gdańsk, 11/12 Narutowicza Str., 80-952 Gdańsk, Poland,

Bibliografia

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