# The influence of non-isothermal flows in the Taylor-Couette instability through numerical analysis

## Palavras-chave:

Taylor-Couette, CFD, Instability, OpenFOAM## Resumo

The Taylor-Couette flow is a classic rotational flow studied since the beginning of the 20th century. The

phenomenon occurs in the gap between two cylinders with different rotational velocities. It happens when one of

the cylinders, usually the inner one, has a rotation that causes centrifugal forces higher than the viscous forces.

The most recognizable characteristic of the flow is the Taylor vortex, an eddy-like pattern that appears across

the cylinders length. The present simulation of Taylor-Couette in the gap inside an electric machine considers

an aspect ratio air gap - cylinder length of 1:20 and the radius rate of 0.9859. The present work evaluates the

necessary rotation, under the geometric conditions presented, to form the Taylor vortices in isothermal flow and

when the flow is submitted to temperature gradients. The GCI method is used to validate the grid dependency. We

have observed and discussed the sensibility of temperature gradients to the identification of the critical flow, to the

velocity field and to the torque at the outer cylinder.