Join us in welcoming the University of Applied Science Western Switzerland and learn about 3 technologies in energy savings and sustainable development.
6:30 pm doors open
7:00 pm the potential of heat flux conversion to electrical power by the magnetic Curie wheel method, Prof. Peter Egolf
7:20 pm magnetic refrigeration at room temperature, Prof. Osmann Sari
7:40 pm fuel Cell Boat Developments, Prof. Jean-Francois Affolter
8:00 pm Q&A;’s, finger food & networking
9:30 pm doors close
The Potential of Heat Flux Conversion to Electrical Power by the Magnetic Curie Wheel Method
By Prof. Dr. Peter W. Egolf
The basic method of magnetic power conversion is shown by the Curie wheel. A flame heating a cylindrical wheel in a magnetic field asymmetrically leads to a rotation, which creates mechanical energy. This energy may be transformed to electrical energy. If the wheel is kept stable by levitation and solar radiation is absorbed, it is named Palmy wheel after the Swiss inventor and physicist Claudio Palmy. The magneto-thermodynamic theory of the movement of this wheel is outlined and an experiment is shown in a movie.
Such magnetic power conversion in corresponding machines has its roots in inventions of Tesla and Edison (patents) and also Einstein (publication). If instead of a small heat absorption in a peripheral area of the wheel, a porous wheel is applied, one may absorb much higher amounts of heat by a transport by forced convective fluid flow through the porous structure. The University of Applied Sciences of Western Switzerland owns a patent for this invention. All the presented results of studies of magnetic power engines are based on the ideas outlined in this patent. Furthermore, large improvements of magnetocaloric materials make a reintroduction of this method into the domains of recent science and technical applications highly attractive.
The main objective is to present different applications of heat utilization, where magnetic power conversion presents a good alternative to conventional power conversion technologies. A selection of magnetic power conversion systems, which are most feasible and economic, is listed. Magnetic power generator machines, based on permanent and superconducting magnets are analyzed for numerous heat source temperatures, magnetic field strength and rotational frequencies. The special analysis takes advantage of a new derived model, which permits to determine the thermodynamic efficiency, the exergy efficiency, the total mass and volume of a magnetic power conversion machine.
Preliminary results show that systems based on permanent magnets are limited to approximately 140-160°C heat source temperature, whereas systems with superconducting magnets could permit a much wider range of applications with an upper limit at approximately 600°C heat source temperature, if a magnetic field of 10 Tesla magnetic flux density is applied. This study shows that magnetic power conversion could beat conventional technologies in many aspects. This is especially the case for low exergy heat sources, where most of the conventional energy conversion technologies cannot even operate. In contrast the magnetic power conversion technology for these sources leads to a high exergy efficiency of energy conversion. Despite of the low thermodynamic efficiency of machines operating with such sources, the available energy potential is nearly unlimited large. Another advantage of magnetic power conversion machines is that they work favourable with a temperature difference actually independent of the height of the temperature levels of the source and sink.
Magnetic Refrigeration at Room Temperature
By Prof. Dr. Osmann Sari
There are two processes to produce cold. The physical process-change of state with compression and expansion and a physical-chemical process (an absorption system). The first machine of refrigeration with compression/expansion was created by Jacobs Perkins in 1834, which was operated with ether as cooling agent. It was in 1931 when the refrigeration industry witnessed the major developments of the refrigerants like CFC R12, HCFC R22 (in 1935) and CFC – R502 (in 1961), HFC R134 (in 1993), etc.
The synthetic refrigerants impact on the environment and newly imposed safety measures force the cooling industry to seek for solutions to remove certain gases or to decrease their content in numerous different systems. In order to become free from the synthetic refrigerants, industrialists are unceasingly searching for environmentally friendly and suitable new technologies also enabling energy savings. During the last ten years the load reduction of refrigerants in installations and the development and use of natural, non-flammable and environment preserving cooling agents became the two preferred methods to improve the current problematic situation. The research on the future technologies orients itself on the ice slurry and CO2 hydrate slurry technology (indirect cooling methods), CO2 vapour compressor technology, thermal electric refrigeration, thermal acoustic refrigeration and magnetic refrigeration (MR). Magnetic refrigeration based on the magneto caloric effect (MCE) of magneto caloric material (MCM) is a highly interesting solution with a good potential to penetrate into some refrigeration markets.
A research team at the Institute of Thermal Sciences and Engineering at the University of Applied Sciences of Western Switzerland have worked out and deposited different patents on the principle of a rotary magnetic refrigerator with a porous wheel. The magneto caloric material consists of Gadolinium spheres and they are encapsulated in different compartments. The induction of the magnetic field in this type of machine is approximately 0.8 Tesla. The carrier fluid is air. A recently developed new prototype, applying a permanent magnets assembly, is capable to achieve a large magnetic field of two 2 Tesla field induction. Contact: Osmann.email@example.com
Fuel Cell Boat Developments in Switzerland
By Prof. Dr. Jean-François Affolter
Legislation for air emissions and water pollution is getting more restrictive for lakes and fresh water. Fuel cell (FC) technology is a solution to replace internal combustion engines based on gasoline fuel. With a better efficiency, zero emission and almost zero noise, FC boats offer a viable alternative that delivers effective motorized navigation while protecting fresh water drinking resources. Experiences with a few FC boats in Switzerland will be presented. Opportunities and limitations for the FC technology applied to navigation will be discussed.
Photo: Myleen Hollero