Double diffusive magneto-convection in viscoelastic fluids

Abstract We investigate the effect of an external magnetic field on the heat and mass transport in double diffusive convection in a viscoelastic fluid layer. The Oldroyd-B constitutive equation is used to model viscoelasticity. Nonlinear stability analysis is carried out using a minimal representation of a Fourier series consisting of two terms. A novel transformation due to Siddheshwar et al. [25] is used in the momentum equation in deriving the non-autonomous generalized Lorenz model. The generalized Lorenz system has been solved numerically using the Runge–Kutta–Fehlberg (RKF45) method to quantify the heat and mass transport. It is established that the applied magnetic field has a stabilizing effect, hence reducing heat and mass transport.

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