Showing papers in "International Journal of Multiphase Flow in 2000"

TL;DR: In this paper, the authors compare time, frequency and state-space analyses of pressure measurements from fluidized beds, and show that the results from the frequency domain (power spectra) and state space analyses (correlation dimension, D ML, and Kolmogorov entropy, K ML, together with a nonlinearity test) are generally in agreement and can be used complementary to each other.

TL;DR: In this article, a Lagrange-multiplier-based fictitious-domain method (DLM) for the direct numerical simulation of rigid particulate flows in a Newtonian fluid was presented, where the flow in the particle domain is constrained to be a rigid body motion by using a well-chosen field of Lagrange multipliers.

TL;DR: In this article, the flow structure occurring during the cocurrent flow of oil (1.6 mPa s viscosity and 801 kg/m(3) density) and water was investigated using two 1in. nominal bore horizontal test sections made from stainless steel and acrylic resin respectively.

TL;DR: In this article, two-phase flow pressure drop measurements were made during a phase-change heat transfer process with three refrigerants (R-134a, R-12, and R-113) at six different pressures ranging from 138 to 856 kPa.

TL;DR: In this paper, a model for the carrier phase turbulence in a fluid-particle flow based on the volume-averaged equations for the kinetic energy of the carrier is introduced.

TL;DR: In this article, an experimental and computational study of the flow behavior in a cold flow laboratory scale circulating fluidized bed reactor was performed using LDOppler Anemometry and Phase DopplerAnemometry techniques to measure mean and fluctuating velocity, diameter and solid concentration, simultaneously.

TL;DR: The relationship between air content and bubble frequency has a parabolic shape, which is not yet understood but was observed previously in open channel flows as mentioned in this paper, and the results indicate an advective diffusion of air in the shear layer.

TL;DR: In this paper, the transition characteristics of flow pattern and phase distribution were studied experimentally in upward air-water two-phase flow along a large vertical pipe (inner diameter D: 0.2 m, the ratio of pipe length to diameter L/D: 61.5).

TL;DR: In this paper, the authors investigated the flow and surface structure in laminar wavy films over a Reynolds number range from Ref=ρūδf/η=27-200.

TL;DR: In this article, a new film thickness and pressure gradient data were obtained in a 5.08 × 101.6 mm duct for nitrogen and water in cocurrent upward annular flow, and these data were used to compute interfacial shear stresses and interfacial friction factors for comparison with several accepted literature correlations.

TL;DR: In this paper, an electrical-impedance tomography (EXT) system was used for two-phase flow measurements, and the results were compared to an established gamma-densitometry tomography system.

TL;DR: In this article, the motion of a single and two lines of neutrally buoyant circular cylinders in fluid between flat parallel walls is numerically investigated over the range of the Reynolds number of 12 < Re < 96.

TL;DR: In this article, the authors compare simulations of a free fluid drop under no-gravity conditions with suspended, large drop experiments at high, low and intermediary temperatures and in a range of pressures encompassing the sub- and supercritical regime.

TL;DR: In this paper, a monodisperse stream of drops which are generated by a vibrating-orifice drop generator was injected into a transverse high velocity gas stream, and the results showed that the microscopic breakup process is similar even at high gas densities.

TL;DR: In this paper, a physically based model was developed to predict the void fraction for upward cross-flow through horizontal tube bundles, which can be used to obtain better estimates of void fraction in the shell side flow in applications such as kettle reboilers and the U-bend region of nuclear steam generators.

TL;DR: In this article, the deformation and drainage of the film between colliding drops are studied numerically at small capillary numbers, small Reynolds numbers and a range of dispersed to continuous-phase viscosity ratios, covering the transition from partially-mobile to immobile interfaces.

TL;DR: In this article, an experimental investigation into adiabatic gas-liquid counterflow in inclined and vertical rectangular ducts with a square-edged gas inlet is conducted, where water, methanol, propanol, air, argon, helium and hydrogen are used as working fluids.

TL;DR: In this article, the hydrodynamic flow behavior in a Gas-Liquid Cylindrical Cyclone (GLCC) compact separator is studied experimentally and theoretically and new experimental data are acquired utilizing a 7.62 cm I.D, 2.18 m high, GLCC separator for a wide range of operating conditions.

TL;DR: In this article, the authors investigated the temporal instability behavior of non-Newtonian liquid jets moving in an inviscid gaseous environment for axisymmetrical disturbances and derived the corresponding dispersion relation between the wave growth rate and the wave number.

TL;DR: In this article, a force-law model for hydrodynamic interactions within the bubble chain was proposed, where three forces acted on each bubble: buoyancy, viscous drag, and inviscid inertia forces.

TL;DR: In this paper, a single-photo/high photography method is applied to measure boiling parameters and the experimental results show the shift of the boiling curve and the delay of ONB and CHF to a higher heat flux by an electric field.

TL;DR: In this paper, a dilute turbulent gas-solid two-phase flow model was developed to study the steady state flow in a vertical pipe and good agreement was found between the simulation prediction and the experimental data for the mean fluid and solid velocities.

TL;DR: In this article, a review of the literature has revealed the lack of a formal analysis of the performance of phenomenological methods for the prediction of pressure drop during gas-liquid two-phase flow.

TL;DR: In this paper, the effects of vortex structures on the solid particle dispersion process in a plane wake were analyzed using laser sheet pulsed imaging of glass bead particles in a wake downstream of a blunt trailing edge.

TL;DR: In this paper, a laser focus displacement meter was used to measure the thickness of a film flowing down the inner wall of a vertical tube, with a sensitivity of 0.2 μm and 1 kHz.

TL;DR: In this paper, the authors presented the pressure gradient and holdup data for air-water and air-oil flows in a horizontal, 0079 m diameter pipe, and compared with predictions of the "apparent rough surface" (ARS) and the "double-circle" models.

TL;DR: In this article, the effects of shear and elongation on drop deformation were examined through numerical simulation and experiment, and a two-dimensional formulation within the scope of the boundary element method (BEM) was proposed for a drop moving under the influence of an ambient flow inside a channel of a general shape.

TL;DR: In this article, the effect of small downward inclinations on the formation of slugs was examined with air and water at atmospheric pressure, in a pipe with a diameter of 0.0763 m, a length of 23 m and inclinations of − 0.2, −0.5, and −0 8°.

TL;DR: In this paper, the authors proposed a correlation method consisting of a combination of the phase Froude numbers and the Ohnesorge number, which succeeded in correlating the data of two previous investigations.