TY  - JOUR
T1  - Experimental Investigation of Circumferential Temperature Variation in Large-Diameter Wickless Glass Heat Pipes
AU  - Özsoy, Ahmet
AU  - Kayacan, Ayşe
PY  - 2025
DA  - September
Y2  - 2025
DO  - 10.35378/gujs.1609655
JF  - Gazi University Journal of Science
PB  - Gazi University
WT  - DergiPark
SN  - 2147-1762
SP  - 1346
EP  - 1357
VL  - 38
IS  - 3
LA  - en
AB  - This study investigates the circumferential temperature distribution in large-diameter wickless glass heat pipes under different inclination angles and heat loads. The experimental analysis was carried out on borosilicate glass heat pipes using ethanol as the working fluid. Surface temperatures were recorded at several axial and circumferential positions under heat loads ranging from 25 W to 100 W and inclination angles of 30°, 60°, and 90°. The results showed that heat transfer efficiency and thermal resistance varied significantly with inclination angle. The system showed optimum performance with lower thermal resistance and higher heat transfer efficiency at 30° and 60° inclination angles. However, increased surface temperatures and dry-out zones at 90° inclination negatively affected the heat transfer efficiency. The results highlight the importance of the use of wicks in the design of glass heat pipes for solar energy applications.
KW  - Glass heat pipe
KW  - Thermosyphon
KW  - Wickless heat pipe
KW  - Thermal resistance
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UR  - https://doi.org/10.35378/gujs.1609655
L1  - https://dergipark.org.tr/en/download/article-file/4477381
ER  -