Experimental determination of void fraction in two-phase flows can be achieved in a number of different ways, including: the quick closing of valves at each end of a test section, impedance measurement techniques, gamma or x-ray absorption, and analysis of visualization results. This paper presents a method of determining void fraction in separated, two-phase refrigerant flows through analysis ...

An accurate prediction of the minimum fluidization velocity is a crucial hydrodynamic aspect of the design of fluidized bed reactors. Common approaches for the prediction of the minimum fluidization velocities of binary-solid fluidized beds are first discussed here. The data of our own careful experimental investigation involving a binary-solid pair fluidized with water is presented. The effect...

Hydrodynamics has a strong influence on substrate elimination capacity in trickle-bed bioreactors (TBB). The present study reports the influence of liquid mass flow rate and bed void fraction on the TBB liquid residence time distribution (RTD), gas-liquid pressure drop, liquid hold-up, and biofilm wetting efficiency. Most RTD are well represented by a dispersion model. It is also shown that the...

Polyolefins have been widely used in the electrical insulation and cable industry in recent years. One of the main usages of these materials is dielectric insulation in coaxial cables. Low attenuation and high signal transmission speed are among the desired features in coaxial cables. The role of polyethylene foam on signal transmission speed in the coaxial cables is the main focus of this stud...

The constitutive equation of AA6082-T6 sheets is investigated by an extended Rousselier damage model. Previous research is mainly comprised of single-pull test specimens, notched tensile specimens, tensile specimens with a hole, and shear specimens. To decrease the natural material errors, a new specimen is used. In this paper, a clinched joint is regarded as a specimen to calibrate the initial...

The newly developed “void expansion method” allows for an efficient generation of porous packings of spherical particles over a wide range of volume fractions using the discrete element method. Particles are randomly placed under addition of much smaller “void-particles”. Then, the void-particle radius is increased repeatedly, thereby rearranging the structural particles until formation of a de...