Viscous heating effects in polymer mechanochemistry

Nonstationary Flows with Viscous Heating Effects

The system of equations describing a nonstationary ow of a quasi-newtonian uid, with temperature dependent viscosity and with the viscous heating, is considered. Existence of at least one weak solution is proved, i.e. we get existence of at least one velocity eld having nite energy and existence of a nonnegative temperature eld. Its regularity is a consequence of the L 1-forcing term generated ...

Extensional flows with viscous heating

We consider the role played by viscous heating in extensional flows of viscous threads with temperature-dependent viscosity. The results show that there exists an interesting interplay between the effects of viscous heating, which accelerates thinning, and inertia, which prevents pinch-off. We consider steady drawing of a thread that is fed through a fixed aperture at given speed and pulled wit...

Polymer mechanochemistry: Flex, release and repeat.

Cluster Heating by Viscous Dissipation of Waves

We simulate the effects of viscous dissipation of waves that are generated by AGN activity in clusters of galaxies. We demonstrate that the amount of viscous heating associated with the dissipation of these waves can offset radiative cooling rates in cooling flow clusters of galaxies. This heating mechanism leads to spatially distributed and approximately symmetrical dissipation. The heating wa...

Viscous heating effects in fluids with temperature-dependent viscosity: triggering of secondary flows

Viscous heating can play an important role in the dynamics of fluids with strongly temperature-dependent viscosities because of the coupling between the energy and momentum equations. The heat generated by viscous friction produces a local temperature increase near the tube walls with a consequent decrease of the viscosity and a strong stratification in the viscosity profile. The problem of vis...