As a necessary component, regenerator plays an important role in the refrigeration performance of the pulse tube refrigerator. The objective of this research is to investigate the flow characteristics in a porous regenerator of the pulse tube refrigerators, subjected to oscillating flow. The hydrodynamic and thermal behavior of the regenerator is investigated by considering porous media approac...

The hybrid molten/solid In2O3 - 30-48 wt.% Bi2O3 oxide materials were studied with respect to their transport properties. The conductivities, oxygen ion transport numbers and oxygen permeation fluxes have been measured by using the four-probe DC, volumetric measurements of the faradaic efficiency and gas flow techniques, respectively. We show that the...

• Developments of micro-scale expanders in carbon dioxide cycles are summarized. Comparison between turbines and volumetric analysed. Relations flow rate, pressure ratio rotational speed highlighted. Challenges future development directions for outlined. In recent decades, the cycles, including supercritical cycle, transcritical Rankine cycle refrigeration have been proven effective due to high...

Flattening filter-free (FFF) beams are available on an increasing number of commercial linear accelerators. FFF beams have higher dose rates than flattened beams of equivalent energy which can lead to increased efficiency of treatment delivery, especially in conjunction with increased FFF beam energy and arc-based delivery configurations. The purpose of this study is to quantify and assess the ...

The possibility of volumetric phase recording based on photo-oxidation the side anthracene groups a new polymer with glass transition temperature ~338 K by oxygen that enters layer across boundary atmospheric medium, was established experimentally. Volumetric holographic gratings maximum diffraction efficiency 2.5–9.5% were recorded radiation from He–Ne laser (λ = 633 nm) in layers 5–20-μm thic...

One of the main sources of efficiency loss in heat engines is the inability of a sinusoidally displaced piston engines to approximate the ideal heat volumetric cycles the engines require. While attempts have been made to address this issue in the past, recent developments in Stirling engine technology utilizing rolling diaphragm seals on the cylinders has offered an opportunity to greatly incre...

Recently researchers have been shifting their focus towards learned 3D shape descriptors from hand-craft ones to better address challenging issues of the deformation and structural variation inherently present in 3D objects. 3D geometric data are often transformed to 3D Voxel grids with regular format in order to be better fed to a deep neural net architecture. However, the computational intrac...