Combined effect of temperature and gravity modulations on the onset of convection in an anisotropic porous medium

• Autorzy: Vanishree R. K.
• Języki publikacji: PL

Abstrakty

EN

The combined effect of time-periodic boundary temperature (TBT, also called temperature modulation) and time-periodic body force (TBF, also called gravity modulation) of small amplitude on convection in an anisotropic porous medium is investigated by making a 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 sub-critical motions. With respect to synchronous TBT and TBF for moderate frequency values, the role of the Prandtl number, horizontal porous parameter, mechanical and thermal anisotropy parameters and the Brinkman number in inducing sub-critical instability is delineated. An asymptotic analysis is also presented for small and large frequencies. A comparison is made between the effects of temperature, gravity and combined (temperature + gravity) modulations on convection. The problem illustrates a method of regulating convection.

Słowa kluczowe

PL

porowatość; anizotropia

EN

temperature modulation gravity modulation; porous medium; anisotropy

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2010
• Tom: Vol. 15, no 1
• Strony: 267--291
• Opis fizyczny: Bibliogr. 25 poz., tab., wykr.

Twórcy

autor

Vanishree R. K.

• Department of Mathematics Maharani's Science College for Women Bangalore - 560 001, INDIA,

Bibliografia

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