Open AccessOn the possibility to improve heat transfer of a sphere by natural convection and water mist
Author(s) -
Akram H. Abed,
V. A. Klimova,
С. Е. Щеклеин,
В. М. Пахалуев
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1382/1/012124
Subject(s) - mist , nusselt number , heat transfer , heat flux , thermodynamics , evaporation , mechanics , materials science , natural convection , convective heat transfer , heat transfer coefficient , thermal , meteorology , reynolds number , physics , turbulence
This paper aims to evaluate the effects of water mist on steady natural convection heat transfer from a sphere. Experimental investigations were performed for the Nusselt number (Nu) under a range of water mist concentration in both cases, sphere located in an open volume space with constant surrounding temperature and inside a cylindrical channel with sphere-to-channel diameter ratio (d/D=0.73). The results obtained from the related experimental work indicated that the heat transfer rate was enhanced over that for the single-phase air flow as a result of water mist evaporation on the heated surfaces. Compared to air cooling over a range of heat flux investigated, the percentage enhancement in the overall thermal factor was about 40%, 95.4%, 129.4%, and 156.8% respectively for all water mist concentration. In addition, an empirical correlation was also formulated to estimate the real benefits of using the water mist of the enhanced sphere.