Thermal conductivity is a critical parameter in cryogenics and plays a fundamental role in the design of components operating in cryogenic environments. As cryogenics gain increasing relevance in fields like energy, understanding the low-temperature thermal conductivity of novel materials becomes ever more essential. Meanwhile, the depletion of helium reserves requires the high-energy...
Radiation heat transfer is a crucial mode of heat transfer in vacuum as well as cryogenic environments. However, there is no optimal solution to accurately measuring spectral emissivity over a wide temperature range, especially at cryogenic temperatures. This work designed a cryogenic spectral emissivity measurement system based on radiometric methods, aiming to measure the spectral emissivity...
Accurate temperature measurement is essential for exploring material properties at low temperatures and in magnetic field environments. Resistance temperature thermometers are affected by magnetoresistance, which can cause measurement errors when calibrated solely in zero magnetic fields. Zirconium oxynitride thin films, renowned for their extremely low magnetoresistance, are widely used for...
In the context of the hydrogen economy, transporting hydrogen in liquid state (LH2), instead of the gaseous one, is considered appealing due to the maximization of the energy density. The liquefaction of hydrogen is, however, an expensive process as it requires cryogenic conditions, typically in the range between 20 K and 30 K, depending on operating pressure. To maximize the economic revenue...
With the advancement of micro- and nano-machining technologies, the distance between components in devices has continually decreased, leading to heat fluxes that exceed the radiation limits predicted by Planck's law. These rapidly increasing heat fluxes can have detrimental effects on near-field devices in cryogenic temperatures, such as difficulties in heat dissipation and reduced operational...
Non-contact bearings are required in many applications where friction losses can be excessive. An option for realization of non-contact bearings with superconductors and permanent magnets exists. The bearings are expected to provide stiffness in the radial and axial direction. The present paper explores axial superconducting magnetic bearings (SMB). The axial SMB leverages the Meissner effect...
High temperature superconductors are vulnerable to sudden thermal runaway events, or quenches. The loss of superconductivity and resulting dissipation of energy from the transport current leads to temporary failure of the magnet or power cable, irreversible damage, and possible catastrophic failure of the superconducting component. Voltage based detection of a pre-quench condition is...
