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Applied Mathematics and Mechanics

, Volume 24, Issue 3, pp 274–283 | Cite as

The effect of magnetic fields on low frequency oscillating natural convection with pressure gradient

  • G. C. Sharma
  • Madhu Jain
  • Mahesh Chandra
Article
  • 53 Downloads

Abstract

The oscillating natural convection in the presence of transverse magnetic field with time depending pressure gradient is studied. The analysis of the problem is carried out by assuming that the fluid is flowing in a parallel plate configuration. The emphasis is on low frequency oscillating convective flows induced by g-jitter associated with micro gravity because of their importance to the space processing materials. A general solution for an oscillating flow in the presence of transverse magnetic field is carried out. Some special cases of the oscillating flow and its response to an applied magnetic field are performed. It was observed that the behavior of oscillating free convective flows depends on frequency, amplitude of the driving buoyancy forces, temperature gradient, magnetic field and the electric conditions of the channel walls. In the absence of magnetic field, buoyancy force plays a predominant role in driving the oscillatory flow pattern, and velocity magnitude is also affected by temperature gradients. To suppress the oscillating flow external magnetic field can be used. It is also found that the reduction of the velocity is inversely proportional to the square of the applied magnetic field with conducting wall but directly proportional to the inverse of the magnetic field with insulating wall. Detailed calculations and computational results are also carried out to depict the real situation.

Key words

convection g-jitter acceleration buoyancy force magnetic field pressure gradient 

Chinese Library Classification

O482.51 

2000 MR Subject Classification

76R10 76R99 

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Copyright information

© Editorial Committee of Applied Mathematics and Mechanics 2003

Authors and Affiliations

  • G. C. Sharma
    • 1
  • Madhu Jain
    • 1
  • Mahesh Chandra
    • 1
  1. 1.School of Mathematical SciencesInstitute of Basic ScienceKhandariIndia

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