scholarly journals Experimental investigations of flat plate heat pipes with screen meshes or grooves covered with screen meshes as capillary structure

2012 ◽  
Vol 37 ◽  
pp. 95-102 ◽  
Author(s):  
Frédéric Lefèvre ◽  
Jean-Baptiste Conrardy ◽  
Martin Raynaud ◽  
Jocelyn Bonjour
2012 ◽  
Vol 3 (1) ◽  
Author(s):  
Frédéric Lefèvre ◽  
Stéphane Lips ◽  
Romuald Rullière ◽  
Jean-Baptiste Conrardy ◽  
Martin Raynaud ◽  
...  

2017 ◽  
Vol 17 (01n02) ◽  
pp. 1760018 ◽  
Author(s):  
P. Pandiaraj ◽  
A. Gnanavelbabu ◽  
P. Saravanan

Metallic fluids like CuO, Al2O3, ZnO, SiO2 and TiO2 nanofluids were widely used for the development of working fluids in flat plate heat pipes except magnesium oxide (MgO). So, we initiate our idea to use MgO nanofluids in flat plate heat pipe as a working fluid material. MgO nanopowders were synthesized by wet chemical method. Solid state characterizations of synthesized nanopowders were carried out by Ultraviolet Spectroscopy (UV), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) techniques. Synthesized nanopowders were prepared as nanofluids by adding water and as well as water/ethylene glycol as a binary mixture. Thermal conductivity measurements of prepared nanofluids were studied using transient hot-wire apparatus. Response surface methodology based on the Box–Behnken design was implemented to investigate the influence of temperature (30–60[Formula: see text]C), particle fraction (1.5–4.5 vol.%), and solution pH (4–12) of nanofluids as the independent variables. A total of 17 experiments were accomplished for the construction of second-order polynomial equations for target output. All the influential factors, their mutual effects and their quadratic terms were statistically validated by analysis of variance (ANOVA). The optimum stability and thermal conductivity of MgO nanofluids with various temperature, volume fraction and solution pH were predicted and compared with experimental results. The results revealed that increase in particle fraction and pH of MgO nanofluids at certain points would increase thermal conductivity and become stable at nominal temperature.


2018 ◽  
Vol 39 (5) ◽  
pp. 540-556 ◽  
Author(s):  
Zhangyuan Wang ◽  
Zicong Huang ◽  
Fucheng Chen ◽  
Xudong Zhao ◽  
Peng Guo

In this paper, the micro-channel flat-plate heat pipes-based BIPV/T system has been proposed, which is expected to have the characteristics, e.g. reduced contact thermal resistance, enhanced heat transfer area, improved heat transfer efficiency and building integration. The proposed system was constructed at the laboratory of Guangdong University of Technology (China) to study its performance. The temperatures of the glass cover, PV panel, micro-channel flat-plate heat pipes, and tank water were measured, as well as the ambient temperature. The thermal and electrical efficiency was also calculated for the system operated under the conditions with different simulated radiations and water flow rates. It was found that the proposed system can achieve the maximum average overall efficiency of 50.4% (thermal efficiency of 45.9% and electrical efficiency of 4.5%) for the simulated radiation of 300 W/m2 and water flow rate of 600 L/h. By comparing the proposed system with the two previous systems employing the conventional heat pipes, the thermal efficiency of the proposed system was clearly improved. The research will develop an innovative BIPV/T technology possessing high thermal conduction capability and high thermal efficiency compared with the conventional BIPV/T system, and helps realise the global targets of reducing carbon emission and saving primary energy in buildings. Practical application: This novel BIPV/T employing micro-channel flat-plate heat pipes will be potentially used in buildings to provide amount of electricity and thermal energy. The generated electricity will be used by the residents for electrical devices, and the thermal energy can be used for hot water, even for space heating and cooling.


2008 ◽  
Vol 51 (15-16) ◽  
pp. 4083-4094 ◽  
Author(s):  
Frédéric Lefèvre ◽  
Romuald Rullière ◽  
Guillaume Pandraud ◽  
Monique Lallemand

2004 ◽  
Vol 28 (2-3) ◽  
pp. 249-255 ◽  
Author(s):  
Yimin Xuan ◽  
Yuping Hong ◽  
Qiang Li
Keyword(s):  

2010 ◽  
Vol 132 (11) ◽  
Author(s):  
Stéphane Lips ◽  
Frédéric Lefèvre ◽  
Jocelyn Bonjour

Thermal and hydrodynamic experimental results of a flat plate heat pipe (FPHP) are presented. The capillary structure is made of crossed grooves machined in a copper plate. The shape of the liquid-vapor interface in this type of capillary structure—that can also be viewed as an array of posts—is studied theoretically and experimentally. A confocal microscope is used to visualize the liquid-vapor interface and thus the capillary pressure field in the system. These hydrodynamic measurements, coupled to temperature measurements on the FPHP wall, are used to estimate the permeability and the equivalent thermal conductivity of the capillary structure filled with methanol or FC72. These parameters are obtained from a comparison between the experimental data and an analytical model. Finally, the model is used to compare the draining capability of crossed grooves with that of longitudinal grooves.


2003 ◽  
Vol 34 (3) ◽  
pp. 187-194 ◽  
Author(s):  
M.J Rightley ◽  
C.P Tigges ◽  
R.C Givler ◽  
C.V Robino ◽  
J.J Mulhall ◽  
...  
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document