Effect of evaporator surface enhancement on the performance of a two-phase closed loop thermosyphon

• Autorzy: Akhanda M. , Mahmood S.
• Języki publikacji: EN

Abstrakty

EN

A two-phase closed loop thermosyphon has been designed, fabricated and tested. This thermosyphon consists of four components in its loop: an evaporator with boiling enhancement structure, vapor rising tube, condenser and condensate return tube. Tests are conducted at atmospheric pressure to assess the effects of evaporator surface geometry using three working fluids (acetone, ethanol and methanol). Four different evaporator surfaces namely smooth surface (SS), semicircular ribbed surface (SCRS), triangular ribbed surface (TRS) and saw tooth ribbed surface (STRS) have been tested in this study. Evaporator surface is heated by using an electric capsule heater which is connected to the AC power supply. Heat supply is varied using a voltage regulator which is measured by a precision ammeter and a voltmeter. Condenser section is cooled by natural circulation of air. Temperatures at different locations of the evaporator surface are measured using calibrated K type thermocouples. It is found that STRS shows the best performance among all the evaporator surfaces tested in this study and among all the working fluids used ethanol's performance is the best.

Słowa kluczowe

EN

evaporator; Surface enhancement

PL

rozwinięcie powierzchni; termosyfon; Thermosyphon; wyparka

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN ; Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archives of Thermodynamics
• Rocznik: 2009
• Tom: Vol. 30, no. 1
• Strony: 63--72
• Opis fizyczny: Bibliogr. 9 poz.,Rys., wykr.,

Twórcy

autor

Akhanda M.

autor

Mahmood S.

• Department of Mechanical and Chemical Engineering, Islamic University of Technology, Board Bazar, Gazipur-1704, Bangladesh

Bibliografia

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