Publications

This study investigates, both experimentally and numerically the flow of a dielectric fluid confined between two concentric, differentially heated, horizontally aligned cylinders subjected to a 200 Hz …ed to a 200 Hz alternating radial electric field. A wide-gap annular setup with a length 20 times larger than the gap size is utilized in this investigation. The study focuses exclusively on the outward heating configuration, meaning the inner cylinder is hotter than the outer one. The electric field, in conjunction with the temperature gradient, triggers thermal electro-hydrodynamic instability caused by the application of dielectrophoretic force. when the applied electric tension exceeds a critical value for specific temperature gradients between the cylinders, the flow symmetry in the gap is disturbed. The instability manifests as periodically oscillating vortices occurring on top of the gap. A notable increase in heat transfer efficiency accompanies the onset of instability. The experimental and numerical results demonstrate quantitative and qualitative agreement.

The Poisson-Boltzmann equation(PBE) is a fundamental equation for accurate description of electrostatics in ionic solutions or plasma. Hence, it finds application in a wide variety of fields including … plasma physics, computational biology, colloidal and interface science and chemistry. In this preprint, we describe a first approach for solving it in a linearized setup using the CutFEM method in the software framework HiFlow3. The considered methods are easy to use, but not oriented towards extracting optimal computing time. Forthis purpose,the weak form of the linear PBE is first derived. Then, the CutFEM based numerical method is proposed. Finally, the most important code sections in HiFlow 3 are explained in more details. The electrostatic potential for ubiquitin and the adenovirus virion molecules are calculated and presented in a numerical example at the end of the paper.