Numerical Study of Buoyancy Convection of Air under Permanent Magnetic Field and Comparison with That under Gravity Field

Mathematical Problems in Engineering. 2014;2014 DOI 10.1155/2014/494585

 

Journal Homepage

Journal Title: Mathematical Problems in Engineering

ISSN: 1024-123X (Print); 1563-5147 (Online)

Publisher: Hindawi Limited

LCC Subject Category: Technology: Engineering (General). Civil engineering (General) | Science: Mathematics

Country of publisher: United Kingdom

Language of fulltext: English

Full-text formats available: PDF, HTML, ePUB, XML

 

AUTHORS


Kewei Song (Department of Mechanical Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China)

Wenkai Li (Department of Mechanical Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China)

Yang Zhou (Department of Mechanical Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China)

Yuanru Lu (Department of Mechanical Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China)

EDITORIAL INFORMATION

Blind peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 26 weeks

 

Abstract | Full Text

Magnetothermal free convection of air in a square enclosure under a nonuniform magnetic field provided by a permanent neodymium-iron-boron magnet is numerically studied. The natural convection under the gravity field alone is also studied for comparison. The physical fields of magnetizing force, velocity, and temperature as well as the local distribution characteristic of Nusselt number are all presented in this paper. The results show that the buoyancy convection of air in the square enclosure under magnetic field is quite different from that under the gravity field. The local value of Nusselt number under the magnetic field supplied by a permanent magnet with a residual magnetic flux density of about 4.5 Tesla can reach a high value of about three times larger than the maximum local value of Nusselt number under the gravity field. Relatively uniform distributions of temperature gradient and Nusselt number can be obtained along the cold wall of the enclosure under the magnetic field. A permanent magnet with high magnetic energy product with Br reaching to 3.5 Tesla can play a comparative role on the averaged Nusselt number compared with that under the gravity environment.