Absolute and convective instabilities in the incompressible boundary layer on a rotating disk with temperature-dependent viscosity

The absolute and convective instability of Von-Kármán rotating disk flow with a temperature dependence viscosity of the form μ = zμ∞ [1 + ε(T - T∞)/Tω - T ∞)] is investigated. With the use of a spectral method, the linear stability equations are formulated and then solved numerically. Solutions have been obtained for various values of the parameter ε which controls the temperature dependence of viscosity. It is established the stability of the flow is particularly sensitive to changes in viscosity and even for small positive values of ε the flow is much more unstable compared to the constant viscosity case. © 2004 Published by Elsevier Ltd.