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Thermal convection in a cylindrical annulus heated laterally

S. Hoyas·H. Herrero·A. M. Mancho
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Abstract

In this paper we study thermoconvective instabilities appearing in a fluid within a cylindrical annulus heated laterally. As soon as a horizontal temperature gradient is applied a convective state appears. As the temperature gradient reaches a critical value a stationary or oscillatory bifurcation may take place. The problem is modelled with a novel method which extends the one described in (numerico). The Navier Stokes equations are solved in the primitive variable formulation, with appropriate boundary conditions for pressure. This is a low order formulation which in cylindrical coordinates introduces lower order singularities. The problem is discretized with a Chebyshev collocation method easily implemented and its convergence has been checked. The results obtained are not only in very good agreement with those obtained in experiments, but also provide a deeper insight into important physical parameters developing the instability, which has not been reported before.

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S. Hoyas, H. Herrero, A. M. Mancho. 2002-03-20. Thermal convection in a cylindrical annulus heated laterally. https://doi.org/10.1088/0305-4470%2F35%2F18%2F306

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