Effect of foldability on the start-up behavior and thermal performance of flexible pulsating heat pipe

• Published in: Heat and mass transfer Vol. 59; no. 3; pp. 439 - 447
• Main Authors: Solanki, Ankursinh, Kapadia, Ragesh G.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2023; Springer Nature B.V
• Subjects: Adiabatic flow; Deionization; Engineering; Engineering Thermodynamics; Evaporation; Evaporators; Heat; Heat and Mass Transfer; Heat pipes; Heat transfer; Heating; Industrial Chemistry/Chemical Engineering; Original Article; Thermal energy; Thermal resistance; Thermodynamics; Working fluids
• ISSN: 0947-7411; 1432-1181
• DOI: 10.1007/s00231-022-03273-4

In this Paper, a Flexible Pulsating Heat Pipe (FPHP) was experimentally tested to evaluate the effect of foldability on the start-up, overall thermal resistance and evaporator temperature. Evaporator and condenser sections were made of 9 turn copper capillary of 2 mm inner diameter. Adiabatic section was made of a silicon rubber tube with an inner diameter of 3 mm. Deionized water with 50% filling ratio was used as working fluid. Heating power range kept was 10–100 W. Four different structural styles (Vertical, 45-Degree, 60-Degree and 90-Degree) created by deforming adiabatic section were experimentally tested and compared. The results show that FPHP showed efficient performance in vertical style
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The minimum thermal resistance found is 0.65 °C/W for vertical style when heating power is 99.88 W. Deformation of adiabatic section degrades start-up and thermal performance of FPHP which depends on the deformation extent. The highest increase in thermal resistance for 90-Degree style is 29.30% for the heating power of 99.88 W when compared with vertical style. Start-up heat input observed is 50.52 W for vertical and 45-Degree styles while it is 60.29 W for 60-Degree and 90-Degree styles. Start-up evaporator temperature increases when the structural style is changed from vertical to 90-Degree.