图书馆订阅: Guest
Begell Digital Portal Begell 数字图书馆 电子图书 期刊 参考文献及会议录 研究收集
国际计算热科学期刊
ESCI SJR: 0.249 SNIP: 0.434 CiteScore™: 0.7

ISSN 打印: 1940-2503
ISSN 在线: 1940-2554

国际计算热科学期刊

DOI: 10.1615/ComputThermalScien.2014010915
pages 405-424

NATURAL CONVECTION HEAT TRANSFER ENHANCEMENT IN A SQUARE CAVITY FILLED WITH NANOFLUIDS AND PERIODICALLY HEATED FROM THE SIDE

M. Hati
Cadi AyyadUniversity, Faculty of Sciences Semlalia, Department of Physics, Laboratory of Fluid Mechanics and Energetics (LMFE), Unit affiliated to CNRST (URAC, 27), B.P. 2390, Marrakech, Morocco
Abdelghani Raji
Sultan Moulay Slimane University, Faculty of Sciences and Technologies, Physics Department, Laboratory of Flows and Transfers Modelling (LAMET), B. P. 523, Béni-Mellal 23000, Morocco
Mohammed Hasnaoui
University Cadi Ayyad, Faculty of Sciences Semlali
Mohamed Naimi
Faculty of Sciences and Technologies, Physics Department, Laboratory of Flows and Transfers Modeling (LAMET), Sultan Moulay Slimane University, B.P. 523, Beni-Mellal, Morocco
H. El Harfi
Faculty of Sciences and Technologies, Physics Department, Laboratory of Flows and Transfers Modeling (LAMET), Sultan Moulay Slimane University, B.P. 523, Beni-Mellal, Morocco

ABSTRACT

Natural convection within a square cavity filled with Cu-water or Al2O3-water nanofluids is investigated numerically. The temperature of the left vertical surface (cold temperature) is maintained constant, while that of the opposite surface (hot temperature) is varied sinusoidally in time. The horizontal walls are considered adiabatic. The parameters governing the problem are the amplitude (0 ≤ a ≤ 1) and the period (0.001 ≤ τ ≤ 1) of the variable temperature, the Rayleigh number (103 ≤ Ra ≤ 106), and the solid volume fraction (0 ≤ φ ≤ 0.1). By adding nanoparticles to the pure fluid, a substantial enhancement of heat transfer is observed. In comparison with the constant heating conditions, it is found that the variable heating temperature could lead to a drastic change in the flow structure and the corresponding heat transfer, especially at specific low periods of the hot variable temperature. This leads to a resonance phenomenon characterized by an important increase in heat transfer by about 25.5% with respect to the case of a pure fluid subject to constant hot temperature boundary conditions.