Enhanced thermal conductivity and viscosity of copper nanoparticles in ethylene glycol nanofluid

2008 ◽  
Vol 103 (7) ◽  
pp. 074301 ◽  
Author(s):  
J. Garg ◽  
B. Poudel ◽  
M. Chiesa ◽  
J. B. Gordon ◽  
J. J. Ma ◽  
...  
Author(s):  
Xin Fang ◽  
Qing Ding ◽  
Li-Wu Fan ◽  
Zi-Tao Yu ◽  
Xu Xu ◽  
...  

Engineered suspensions in the presence of highly-conductive nanoparticles, coined as nanofluids, have been studied extensively as a novel family of advanced heat transfer fluids. Attention has been paid primarily to the enhanced thermal conductivity of the suspensions that depends significantly on the material, size, shape, dispersion and loading of the nanoparticles. In this paper, the effects of adding silver (Ag) nanoparticles of various sizes and shapes on the thermal conductivity of ethylene glycol (EG)-based suspensions were investigated experimentally. These included Ag nanospheres (Ag NSs), Ag nanowires (Ag NWs) and Ag nanoflakes (Ag NFs). The suspensions were prepared at concentrations of 1, 5 and 10 mg/mL. The size and shape of the various Ag nanoparticles were observed by means of microscopy techniques. The dispersion and stability of the suspensions were also inspected. Measurements of the thermal conductivity of the suspensions were performed on a Hot Disk Thermal Constants Analyzer, which is based on the transient plane source technique, at elevated temperatures from 10 to 30 °C at an increment of 5 °C. It was shown that the thermal conductivity of the EG-based suspensions increases with raising the temperature. The Ag NWs of a very high aspect ratio (∼400) caused greatest relative enhancement up to 15.6% at the highest loading of 10 mg/mL (∼0.1 vol.%). The other two types of nanoparticles, Ag NSs and Ag NFs with much smaller aspect ratios, only led to enhancements up to 5%. The formation of a network of Ag NWs that facilitates heat conduction was likely responsible for their better performance. In addition, the relative enhancement was predicted by the Hamilton-Crosser (H-C) equation that takes the shape effect of the particles into consideration. It was shown that the predictions far underestimate the thermal conductivity enhancements but are qualitatively consistent with their shape dependence.


RSC Advances ◽  
2017 ◽  
Vol 7 (1) ◽  
pp. 318-326 ◽  
Author(s):  
Pham Van Trinh ◽  
Nguyen Ngoc Anh ◽  
Bui Hung Thang ◽  
Le Dinh Quang ◽  
Nguyen Tuan Hong ◽  
...  

High thermal conductivity was obtained for nanofluid-based EG containing Cu nanoparticle-decorated Gr–MWCNT hybrid material synthesized by chemical reduction.


2012 ◽  
Vol 55 (13-14) ◽  
pp. 3885-3890 ◽  
Author(s):  
Sivasankaran Harish ◽  
Kei Ishikawa ◽  
Erik Einarsson ◽  
Shinya Aikawa ◽  
Shohei Chiashi ◽  
...  

2021 ◽  
Vol 3 (44) ◽  
pp. 137-141
Author(s):  
Ekaterina P. Parlyuk ◽  

One of the most important elements of the cooling system of any automotive internal combustion engine is a coolant. Most often, water and a mixture of water with antifreeze are used as a coolant. Its main function is to transfer heat or to cool the engine. Nanofluids are promising heat carriers, with the help of which it is possible to reduce the metal consumption of aggregates, increase safety in emergency transient modes accompanied by boiling. (Research purpose) The research purpose is studying the possibilities, features and prospects of using innovative heat carriers as coolants of automotive equipment, which will allow overcoming the inefficiency of water and ethylene glycol mixtures, which consists in low thermal conductivity. (Materials and methods) Nanofluids consisting of a base liquid and nanoparticles of a highly heat-conducting material were proposed as innovative heat carriers. Their use in transport power plant coolers will reduce their volume and weight. Mixing of ethylene glycol and copper nanoparticles is effective, in such cases it is important to investigate the effect of the volume fraction of copper nanoparticles and the base liquid on thermal characteristics or to reduce the size of the radiator. Copper nanoparticles have better thermal conductivity than other nanoparticles (for example, aluminum oxide). (Results and discussion) It has been proved that the use of nanofluids in heating and ventilation systems can give a significant increase in heat transfer. At present the science of nanofluids is in its initial stage, for the development of this direction it is necessary to conduct comprehensive experimental studies of their chemical and physical properties, theoretical analysis, and compilation of general calculated correlations. (Conclusions) It was revealed that nanofluids can be effectively used as heat carriers of transport engines, with their use the metal consumption of coolers is reduced, the safety of units in emergency modes, including those accompanied by boiling, is increased.


2017 ◽  
Vol 59 (02) ◽  
pp. 10-13
Author(s):  
Trong Tam Nguyen ◽  
◽  
Hung Thang Bui ◽  
Ngoc Minh Phan ◽  
◽  
...  

Sign in / Sign up

Export Citation Format

Share Document