Magnetic field control of cryogenic heat pipes
This paper deals with cryogenic heat pipes controlled by static magnetic field. Heat pipe is an equipment which allows a very effective heat transport. They are commonly used in electronic devices and in many other types of equipment as well. Some applications require heat flow controllability. For that purpose heat pipes are modified to many different constructions with variable heat conductance. Magnetic field control of heat transport is a new solution researched in a few laboratories in the world and still not practically applicated. According to the results of some experiments, implemented in our laboratory and several another laboratories, it seems to be possible to control heat transport in chosen types of heat pipes by a static magnetic field. The cryogenic heat pipe filled with pure oxygen has been made for that purpose and a testing device has been arranged as well. We have found out that the heat transport efficiency of the heat pipe has rapidly decreased by a magnetic field exposure. Some interesting results of our experiments will be presented in this paper.
Working Fluid Quantity Effect on Magnetic Field Control of Heat Pipes
This paper deals with heat pipes controlled by a static magnetic field and with an important side effect – the quantity of working fluid. Heat pipes are able to provide very effective heat transport. Several standard regulation methods are commonly used for this purpose. In previous experiments implemented in our laboratory, we have observed the significant influence of a magnetic field on the heat conductance of the selected heat pipe. A special heat pipe was manufactured for this purpose and pure oxygen was chosen as a working fluid, due to its suitable magnetic properties. The heat pipe operation and the magnetic field control depend on various parameters. This paper is focused on the influence of the quantity of working fluid. Some important results of our experiments are presented and discussed.
Investigations of dielectric gratings using electrodynamic models based on volume integral equations
Eigenmodes of planar and cylindrical dielectric gratings (DGs) and electromagnetic wave scattering from multiplayer DGs are investigated. The DG characteristics are calculated using numerical-analytical solution of integral equations (IEs).