The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
T Furukawa - One of the best experts on this subject based on the ideXlab platform.
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prediction of the effects of liquid viscosity on interfacial shear stress and frictional pressure drop in vertical upward gas liquid annular flow
International Journal of Multiphase Flow, 1998Co-Authors: Tohru Fukano, T FurukawaAbstract:Abstract The purpose of the present study is to investigate the effects of liquid viscosity on the mean liquid film thicknesses, wave heights, and gas–liquid interfacial shear stresses in the vertical-upward co-current annular flow in a 26.0 mm inner Diameter Tube. Water and glycerol solutions were used as working fluids to change the kinematic viscosity of liquid from 0.85×10 −6 to 8.6×10 −6 m 2 /s. The mean liquid film thicknesses and wave heights were determined using the signals of time-varying cross-sectionally averaged holdup which were detected by a constant current method at a distance of about 3.5 m from an air–liquid mixer. The pressure gradients were also measured by a U-Tube manometer. As a result we proposed correlations for the mean liquid film thicknesses and the interfacial friction factors. In addition a method to estimate the pressure drops is proposed and verified that the calculated values are in good agreement with the measured values.
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prediction of the effect of liquid viscosity on interfacial shear stress and pressure drop in vertical upward gas liquid annular flow
Transactions of the Japan Society of Mechanical Engineers. B, 1996Co-Authors: T Furukawa, Tohru FukanoAbstract:The purpose of the present study is to investigate the effects of liquid viscosity on the mean liquid film thicknesses, wave heights, and gas-liquid interfacial shear stresses in vertical-upward cocurrent annular flow in a 26.0mm-inner-Diameter-Tube. Water and glycerol solution were used as working fluids in order to change the kinematic viscosity of liquid from 0.85×10-6 to 8.6×10-6m2/s. The mean liquid film thicknesses and wave heights were determined using the signals of time-varying cross-sectionally averaged holdup which were detected by a constant current method at a distance of about 3.5m from an air-liquid mixer. The pressure gradients were also measured by a U-Tube manometer. As a result we proposed correlations for the mean liquid film thicknesses and for the interfacial friction factors. In addition a method for estimating pressure drop was proposed, which verified that the calculated values were in good agreement with the measured values.
Colin L Raston - One of the best experts on this subject based on the ideXlab platform.
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vortex fluidic device intensified aqueous two phase extraction of c phycocyanin from spirulina maxima
ACS Sustainable Chemistry & Engineering, 2016Co-Authors: Xuan Luo, Colin L Raston, Paul A Smith, Wei ZhangAbstract:A vortex fluidic device (VFD) is effective for downstream processing of C-phycocyanin (C-PC) from blue-green microalga Spirulina maxima using an aqueous two phase system (ATPS): polyethylene glycol (PEG) and aqueous potassium phosphate. The VFD-intensified ATPS continuous flow processing (VFD-ATPS) has spontaneous phase separation of the liquid exiting the 20 mm Diameter Tube inclined at 45° and rotating at 6550 rpm, for a 0.2 mL/min flow rate. This processing results in at least a 9.3-fold increase in phase demixing efficiency, 1.18-fold increase in C-PC purity, and 22% increase in yield compared to conventional ATPS methods. Multistage counter current distribution (CCD) using VFD-ATPS followed by removal of PEG and salt increased C-PC purity by 6-fold compared to the crude extract, with triple TOF mass spectrometry showing more than 95% sequence coverage for both subunits. This work establishes the utility of using VFD-intensified ATPS processing for protein purification and its potential as an effectiv...
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rapid high conversion of high free fatty acid feedstock into biodiesel using continuous flow vortex fluidics
RSC Advances, 2015Co-Authors: Joshua Britton, Colin L RastonAbstract:Conversion of high free fatty acid (FFA) feedstock (94.4%) to biodiesel with undetectable FFA content is effective using room temperature vortex fluidic flow chemistry, with the conversion taking <1 minute residence time, using dramatically less methanol and acid catalyst compared to other processes. Optimum conditions are 1:6 volumetric ratio of oil feedstock to methanol and 0.2 molar equivalents of H2SO4 catalyst loading, for a combined flow rate of 3.50 mL min−1 in a 17.7 mm internal Diameter Tube rotating at 7500 rpm. This work furthers the viability of using high FFA content feedstocks for biodiesel production.
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Optimising a vortex fluidic device for controlling chemical reactivity and selectivity
Scientific Reports, 2013Co-Authors: Lyzu Yasmin, Xianjue Chen, Keith A. Stubbs, Colin L RastonAbstract:A vortex fluidic device (VFD) involving a rapidly rotating Tube open at one end forms dynamic thin films at high rotational speed for finite sub-millilitre volumes of liquid, with shear within the films depending on the speed and orientation of the Tube. Continuous flow operation of the VFD where jet feeds of solutions are directed to the closed end of the Tube provide additional tuneable shear from the viscous drag as the liquid whirls along the Tube. The versatility of this simple, low cost microfluidic device, which can operate under confined mode or continuous flow is demonstrated in accelerating organic reactions, for model Diels-Alder dimerization of cyclopentadienes and sequential aldol and Michael addition reactions, in accessing unusual 2,4,6-triarylpyridines. Residence times are controllable for continuous flow processing with the viscous drag dominating the shear for flow rates >0.1 mL/min in a 10 mm Diameter Tube rotating at >2000 rpm.
Tohru Fukano - One of the best experts on this subject based on the ideXlab platform.
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prediction of the effects of liquid viscosity on interfacial shear stress and frictional pressure drop in vertical upward gas liquid annular flow
International Journal of Multiphase Flow, 1998Co-Authors: Tohru Fukano, T FurukawaAbstract:Abstract The purpose of the present study is to investigate the effects of liquid viscosity on the mean liquid film thicknesses, wave heights, and gas–liquid interfacial shear stresses in the vertical-upward co-current annular flow in a 26.0 mm inner Diameter Tube. Water and glycerol solutions were used as working fluids to change the kinematic viscosity of liquid from 0.85×10 −6 to 8.6×10 −6 m 2 /s. The mean liquid film thicknesses and wave heights were determined using the signals of time-varying cross-sectionally averaged holdup which were detected by a constant current method at a distance of about 3.5 m from an air–liquid mixer. The pressure gradients were also measured by a U-Tube manometer. As a result we proposed correlations for the mean liquid film thicknesses and the interfacial friction factors. In addition a method to estimate the pressure drops is proposed and verified that the calculated values are in good agreement with the measured values.
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prediction of the effect of liquid viscosity on interfacial shear stress and pressure drop in vertical upward gas liquid annular flow
Transactions of the Japan Society of Mechanical Engineers. B, 1996Co-Authors: T Furukawa, Tohru FukanoAbstract:The purpose of the present study is to investigate the effects of liquid viscosity on the mean liquid film thicknesses, wave heights, and gas-liquid interfacial shear stresses in vertical-upward cocurrent annular flow in a 26.0mm-inner-Diameter-Tube. Water and glycerol solution were used as working fluids in order to change the kinematic viscosity of liquid from 0.85×10-6 to 8.6×10-6m2/s. The mean liquid film thicknesses and wave heights were determined using the signals of time-varying cross-sectionally averaged holdup which were detected by a constant current method at a distance of about 3.5m from an air-liquid mixer. The pressure gradients were also measured by a U-Tube manometer. As a result we proposed correlations for the mean liquid film thicknesses and for the interfacial friction factors. In addition a method for estimating pressure drop was proposed, which verified that the calculated values were in good agreement with the measured values.
Kunihito Matsumura - One of the best experts on this subject based on the ideXlab platform.
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saturated flow boiling of water in a vertical small Diameter Tube
Experimental Thermal and Fluid Science, 2003Co-Authors: Baduge Sumith, Fumito Kaminaga, Kunihito MatsumuraAbstract:Abstract The characteristics of flow boiling heat transfer of water in a vertical Tube with a 1.45 mm Diameter, which is less than the Laplace constant, are experimentally studied under atmospheric pressure and forced flow condition. Local heat transfer coefficients are measured in a range of mass fluxes from 23.4 to 152.7 kg/m2 s, heat fluxes from 10 to 715 kW/m2 and quality up to 0.8. The effects of mass flux, heat flux and quality on the boiling heat transfer coefficient are examined. Large heat transfer enhancement is observed and existing flow boiling correlations largely underpredict the heat transfer coefficient especially for a low heat flux condition. The underprediction gradually decreases with increasing heat flux. The dominant flow pattern in the Tube is a slug-annular or an annular flow, and then liquid film evaporation is found to dominate the heat transfer. A heat transfer prediction method is proposed to reproduce the heat transfer coefficient in the flow pattern. The Katto’s critical heat flux (CHF) correlation consistently predicts the present CHF values but overpredicts by 20%.
Takashi Hibiki - One of the best experts on this subject based on the ideXlab platform.
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experimental study of interfacial area transport of bubbly flow in small Diameter Tube
International Journal of Multiphase Flow, 2003Co-Authors: Tomoji Takamasa, T Goto, Takashi HibikiAbstract:Abstract In relation to the development of the interfacial area transport equation, this study was aiming at collecting accurate data sets on axial developments of local flow parameters such as void fraction, interfacial area concentration, and gas velocity. The local flow measurements of air–water bubbly flow in a vertical 9-mm-Diameter Tube were performed by means of a stereo image-processing method. A total of three data sets were acquired consisting of two gas flow rates, 0.013–0.052 m/s, and two liquid flow rates, 0.58–1.0 m/s at six axial locations. The data would be used for the development of reliable constitutive relations which reflect the true transfer mechanisms in two-phase flow.
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application of neutron radiography to visualization and void fraction measurement of air water two phase flow in a small Diameter Tube
Journal of Nuclear Science and Technology, 1993Co-Authors: Takashi Hibiki, Kaicbirol Mishima, Kenji Yoneda, Shigenori Fujine, Keiji Kanda, Hideaki Nishihara, Akira Tsuruno, Masahito MatsubayashiAbstract:Abstract The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small Diameter Tube (I.D.: 4.08mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No. 2) installed at the Japan Research Reactor 3 M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final results of void fraction in the case of a small Diameter Tube...