Experimental investigation of coupled MHD and thermal radiation effects in Rayleigh-Bénard Convection

• Applicant: Professor Dr.-Ing. Christian Karcher
• Subject Area: Fluid Mechanics ; Technical Thermodynamics
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 467227170

Rayleigh-Bénard Convection (RBC) has been being a classical topic in the area of fluid flow and heat transfer. With the development and progress of science and technology, as well as the cross accommodation of disciplines, new contents and challenges appear in the RBC even after more than one hundred years’ researching. For instance, in the newly arising area of renewable energy research and the traditional aerospace area, the influences of electromagnetic field and/or thermal radiation on fluid flow and heat transfer cannot be ignored anymore. The present research proposal aims to conduct fundamental experimental research of fluid flow and heat transfer in RBC influenced by the combined effects of thermal radiation and electromagnetic fields. The proposed model experiments shall be supported by respective numerical simulations that are no subject for funding within the present proposal. Here, already available and validated in-house codes for RBC under the influence of magnetic fields will be further developed to include the effects of thermal radiation. Systematic fundamental studies in systems, characterized by electrically conducting fluids and high temperatures of operation, have not been performed yet. According to the working experience and the already existing experimental infrastructure the experimental investigations will focus on the temperature range up to 600 K and on the influence of strong external magnet fields up to 5 T. In the frame the present research proposal, an informal cooperation with Prof. Benwen Li of Dalian University of Technology Chinese will be established. At Dalian, the focus will be on the study of high-temperature radiation effects well beyond 600 K in the case when magnetic fields are absent. The precise relations of heat transfer and fluid flow, i.e. the dependence of Nusselt number and Reynolds number on the control parameters Rayleigh number (thermal driving), Planck number (thermal radiation) and Hartmann number (magnetic field) will be systematically revealed. Moreover, the possibility of fluid flow transformation from classical regime to ultimate regime will be explored together with the critical parameters. Combining with engineering applications, the instabilities in high-temperature thermal storage systems and liquid metal batteries will be analyzed, and techniques will be proposed to suppress them.

• DFG Programme: Research Grants
• International Connection: China
• Co-Investigator: Professor Dr.-Ing. Christian Cierpka
• Cooperation Partner: Professor Dr. Benwen Li