Open AccessStudy of diffusion bonded flat plate closed loop pulsating heat pipes with alternating porous media
Author(s) -
Luis Betancur,
Arthur Ronan Facin,
Priscila da Costa Gonçalves,
K.V. Paiva,
Marcia Mantelli,
G. G. V. Nuernberg
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1139/1/012001
Subject(s) - materials science , heat pipe , micro loop heat pipe , heat transfer , composite material , thermal resistance , evaporator , diffusion , tube (container) , diffusion bonding , welding , heat exchanger , mechanics , mechanical engineering , thermodynamics , physics , engineering
This work aims to discuss the application of diffusion bonding process in the fabrication of flat plate pulsating heat pipes and to analyze the thermal performance effect of porous media structures applied to alternating channels in the evaporator section and compare it with a smooth conventional flat plate pulsating heat pipe. For that, two different copper flat plate pulsating heat pipes with five turns and 1.5 mm of inner diameter channels were fabricated, using diffusion bonding. Samples were made with two different diffusion process to evaluate the ability of the resulting device to keep the vacuum, avoiding the use of filler material during the welding process, which could result in contamination and, therefore, undesirable corrosion on both internal and external heat pipe surfaces. The results allowed to assess the quality of the bonded interface of two different configurations of the diffusion process. Microscopic results obtained on controllable pressure furnace and non-pressure control were analyzed, where the diffusion process with controlled pressure presented best results of continuity, alignment, and tightness. A comparison of the heat transfer characteristics between the two devices was performed under the same experimental conditions; for both devices, the thermal resistance in horizontal position showed to be like heat transfer of pure conductive copper plate. However, pulsating heat pipe containing smooth channels showed the lower thermal resistance in vertical position and filling ratio of 50%.