Effect of viscous dissipation and internal heat source on mono-diffusive thermoconvective stability in a horizontal porous medium layer

A mathematical model is developed for studying the onset of mono-diffusive convective fluid flowin a horizontal porous layer with temperature gradient, internal heat generation and viscousdissipation effects. Darcy’s model is used for the porous medium which is considered to beisotropic and homogenous. A linear instability analysis is conducted and transverse or longitudinalroll disturbances are examined. The dimensionless emerging eigenvalue problem is solvednumerically with Runge-Kutta and shooting methods for both cases of disturbances i.e.longitudinal and transverse rolls. Critical wave number and critical vertical thermal Rayleighnumbe