Influence of Micropolar Parameters on the Stability Domain in a Rayleigh-Bénard Convection Problem–A Reliable Numerical Study (original) (raw)
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JOURNAL OF ADVANCES IN MATHEMATICS
The effect of gravity modulation (time periodic body force or g-jitter) on the onset of Rayleigh-Bénard convection in a micropolar fluid with internal heat generation is investigated by making a linear stability analysis. The stability of a horizontal layer of fluid heated from below is examined by assuming time periodic body force in the presence of internal heat source. A regular perturbation method is used to arrive at an expression to compute the critical Rayleigh number for small amplitude of modulation and dimensionless internal heat source. The Venezian approach is adopted to obtain the eigen value of the problem. The results obtained during the analysis have been presented graphically.
International Journal of Engineering Research and Technology (IJERT), 2013
https://www.ijert.org/the-effect-of-imposed-time-periodic-boundary-temperature-and-electric-field-on-the-onset-of-rayleigh-bnard-convection-in-a-micropolar-fluid https://www.ijert.org/research/the-effect-of-imposed-time-periodic-boundary-temperature-and-electric-field-on-the-onset-of-rayleigh-bnard-convection-in-a-micropolar-fluid-IJERTV2IS70350.pdf The effect of imposed time periodic temperature of small amplitude and AC electric field on the onset of Rayleigh-Bénard convection in a micropolar fluid is investigated using linear stability analysis. A regular perturbation method is used to arrive at an expression for the correction Rayleigh number that throws light on the possibility of subcritical motions. The Venezian approach is adopted for obtaining eigen value of the problem. Three cases of oscillating temperature field are examined: (a) symmetric, so that the wall temperatures are modulated in-phase, (b) asymmetric, corresponding to out-of-phase modulation and (c) only the lower wall is modulated. It is observed that the system is most stable when the boundary temperatures are modulated out-of-phase. This problem is an example of external control of the internal convection.
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International Communications in Heat and Mass Transfer, 2010
A linear stability analysis was conducted to assess the feasibility of using a feedback control strategy on the onset of Bénard-Marangoni convection in a micropolar fluid. The single-term Galerkin technique was used to obtain the closed-form solution for the Marangoni number M for the onset of convection, satisfying three different non-uniform basic state temperature profiles. It is demonstrated that the controller gain parameter can successfully increase the critical Marangoni number.