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Volume 20 (1987)
- Issue 6 Pages 557-
- Issue 5 Pages 443-
- Issue 4 Pages 335-
- Issue 3 Pages 213-
- Issue 2 Pages 111-
- Issue 1 Pages 1-
Volume 20, Issue 5
Displaying 1-17 of 17 articles from this issue
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TAKAAKI OHTAKE, TADASHI HANO, KAZUMI TAKAGI, FUMIYUKI NAKASHIO1987 Volume 20 Issue 5 Pages 443-447
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThe drop diameter of W/O emulsion dispersed in water was measured in a stirred tank. The Sauter mean drop diameter (d32) in an emulsion of low viscosity was inversely proportional to the square root of the Weber number which expressed the contribution of impeller diameter, agitation speed, and interfacial tension. In addition, d32 of highly viscous emulsion was proportional to the 0.8 power of the apparent viscosity. The drop diameter also varied with the method of pouring the emulsion into water.View full abstractDownload PDF (349K) -
JONG WON KIM, WON KOOK LEE1987 Volume 20 Issue 5 Pages 448-453
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSCoalescence frequency and lifetimes of thin aqueous films formed between nitrogen bubbles were measured in dilute solutions of sodium lauryl sulfate, n-amyl alcohol, and 1-butanol. The bubble pairs were formed on two adjacent capillary tubes by use of a microprocessor-controlled stepping motor, and the coalescence time was determined by an optical sensing method.
For low-molecular weight alcohols such as 1-butanol and n-amyl alcohol, the transition concentration decreased with increase of bubbling frequency. But for high-molecular weight surfactants such as sodium lauryl sulfate, it increased with bubbling frequency. Coalescence times increased with solute concentration and also with surface tension gradient.View full abstractDownload PDF (493K) -
MASABUMI NISHIKAWA, FUYUHIKO MORI, SHIGEO FUJIEDA, TAKASHI KAYAMA1987 Volume 20 Issue 5 Pages 454-459
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThe scale-up effect of mixing vessels on the drop size of a liquid-liquid dispersion is discussed and correlative equations to estimate drop sizes in breakup and coalescence regions are proposed. It is shown that (n3d2D)(4Np/π) is applicable as a scale-up standard and that the average energy dissipation rate, the Weber number in the mixing vessel or the agitational Reynolds number is not a satisfying scale-up standard. It is also shown that the effect of volume fraction of dispersed phase on drop size is affected by the scale-up ratio; that is, the scale-up ratio is expected to have a smaller effect on drop size as the fraction of dispersed phase increases.View full abstractDownload PDF (419K) -
HIDEKI MORI, IKUHO YAMADA, TOSHIHIKO TSUIKI, SETSURO HIRAOKA1987 Volume 20 Issue 5 Pages 460-467
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA successive relaxation algorithm is proposed for the solution of multicomponent distillation problems, where the working equation has less round-off error than the Euler equation.
By applying the weighting average of forward and backward finite difference to the derivative of liquid mole fraction with respect to time, a numerical integration formula of higher accuracy is obtained. Although the resultant equations have implicit form, they are successfully solved by a successive relaxation algorithm after making reasonable assumptions and combining these equations with the summation equation of liquid compositions.
The discussion extends to the method of determining a time increment and a weighting factor based on the results of various numerical examples, so that the proposed algorithm becomes more useful.View full abstractDownload PDF (543K) -
MOTONOBU GOTO, SHIGEO GOTO1987 Volume 20 Issue 5 Pages 467-472
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA cation exchange fiber and a chelating fiber were used to remove copper ions from aqueous solution. Equilibrium isotherms were measured for both fibers. Adsorption breakthrough and desorption curves for the fixed bed of fibers were compared with those for conventional spherical resins. Overall volumetric coefficients were evaluated from the breakthrough curves and then the contributions of respective mass transfer processes were estimated. Also, pressure drops in the fixed bed were measured.View full abstractDownload PDF (442K) -
SHIGEKI TOYAMA, TSUTOMU ARAGAKI, HASSAN MOHAMED SALAH, KAZUNORI MURASE ...1987 Volume 20 Issue 5 Pages 473-478
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA multieffect solar still is simulated by formulating the rate equations and the heat and mass balance equations with respect to the process variables. The results obtained by the simulation showed satisfactory agreement with the experimental data taken from laboratory test plant having five stages and 1 m2 frame area. Calculation with the model showed the effect of design and operation parameters such as solar intensity, heat transfer coefficient through the partition and feed rate of brine to each stage on the distillate productivity.
The results showed that the distillate productivity is independent of overall heat transfer coefficient through the partition if its value becomes higher than 230 W/m2⋅K. Correlation to obtain the feed rate at each stage required to maximize the productivity of distillate was obtained as a function of the solar intensity and ratio of brine feed between two successive stages.View full abstractDownload PDF (401K) -
TATSUO NISHIMURA, TADASHI YOSHINO, YUJI KAWAMURA1987 Volume 20 Issue 5 Pages 479-485
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA numerical analysis of pulsatile flow in a wavy channel with periodically converging-diverging cross sections was carried out by the finite element method. The variations of streamline and wall shear stress with Womersley number A*, Reynolds number Re and oscillatory fraction of the flow rate P were studied.
A recirculation vortex occurs within the furrow of the wall during the acceleration phase for inertia-dominated flow but during the deceleration phase for viscosity-dominated flow. Its boundary is determined in terms of A*2/Re. As Re or P increases, higher modes appear in the time variation of wall shear stress owing to the non-linear effects, and also a kind of Reynolds stress occurs in the time-averaged wall shear stress.
An experimental flow visualization study additionally performed shows good agreement with the numerical analysis.View full abstractDownload PDF (925K) -
IBRAHIM A. KHATTAB, MASARU ISHIDA1987 Volume 20 Issue 5 Pages 485-492
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSBased on experimental observations, some of which were carried in our laboratory, a simple computer simulation model or a simulator to predict the spatiotemporal behavior of bubbles in freely bubbling three-dimensional gasfluidized beds of Group B particles is developed. In this simulator a few criteria have superseded the more sophisticated models for the treatment of interaction and coalescence of bubbles and hence it requires less computational effort. For both laboratory- and large-scale fluidized beds the spatial distribution of bubble diameter as well as that of bubble frequency at any level above the distributor and at various superficial gas velocities were satisfactorily estimated from qualitative and quantitative standpoints. The operation of the simulator was extended to predict the distribution of the fluidizing gas between the continuous and discontinuous phases and the change of coalescence frequency with the height above the distributor. Good agreement with related data reported in the literature was obtained as well.View full abstractDownload PDF (697K) -
KOSAKU ISHIMI, SADATOSHI KOROYASU, HARUO HIKITA1987 Volume 20 Issue 5 Pages 492-498
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSCreeping flow past a square and an equilateral triangular array of cylinders and mass transfer between the fluid and the surface of the cylinders were studied theoretically. A numerical solution for the drag coefficient of the cylinders was obtained and found to be in good agreement with the asymptotic analytical solutions for very small and very large values of the dimensionless pitch respectively. A numerical solution for the Sherwood number was obtained as a function of the Peclet number, the dimensionless pitch, and the number of rows of cylinders in square and triangular arrays. Theoretical predictions for the drag coefficient of the cylinders and the Sherwood number were compared with approximate analytical solutions based on the free-surface model by Happel.View full abstractDownload PDF (498K) -
KUNIO KATO, SINJI KANBARA, TORU TAJIMA, HIDEKI SHIBASAKI, KENJI OZAWA, ...1987 Volume 20 Issue 5 Pages 498-504
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThe elutriation rate constant for the gas-solid fluidized bed with and without vertical multi-tube internals was determined by a continuous steady-state operation. Silica sand, FCC, and glass beads of a wide size distribution were used.
For fine particles belonging to group A of Geldart''s classification, the elutriation rate was not affected by bed internals. For coarse particles, however, the rate was affected by the internals.
The elutriation rate constant for the fluidized bed with multitube internals was affected by the gas velocity, terminal velocity of particles, hydraulic diameter of bed and minimum fluidization velocity. Empirical equations for the elutriation rate constant are presented.View full abstractDownload PDF (412K) -
RECOVERY OF VANADIUM FROM OIL-FIRED BOILER SLAG BY DIRECT LEACHING AND SUBSEQUENT SOLVENT EXTRACTIONIZUMI TSUBOI, MICHIHIKO TAMAKI, JOHN INGHAM, EIICHI KUNUGITA1987 Volume 20 Issue 5 Pages 505-510
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThe recovery of vanadium from oil-fired boiler slag was examined, using the techniques of direct leaching and subsequent solvent extraction. Hydrochloric acid leaching showed the best extraction capability for vanadium and other metals in the oil-fired boiler slag. Sodium hydroxide leaching had the highest selectivity for vanadium. A combination of these two leaching methods hastened the recovery of metals and the separation of vanadium. Alternative processes of solvent extraction employed for metal separation from the leachate with a computer program and the best selected process was verified experimentally. As a result 94% of the vanadium in the oil-fired boiler slag was recovered in pure solution form.View full abstractDownload PDF (495K) -
TING-CHIA HUANG, YIH-KUNG LIN1987 Volume 20 Issue 5 Pages 511-517
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSSome water-soluble metal-chelating agents are introduced into a Donnan dialyzer as the strip agent for the enrichment of nickel ion. The interdiffusion fluxes of Ni2+-Na+ and Ni2+-H+ are found to increase with increasing capability of chelating agent. Experimental results of ion-exchange equilibria indicate that the nickel uptake on the strip-side, membrane-solution interface is reduced in the presence of chelator, which explains the promotion of interdiffusion rate. Effects on the interdiffusion fluxes due to various types of chelating agents, concentrations of chelating agents, concentrations of counterions, and pH value are investigated.
In the presence of strong EDTA ligand, the inter-diffusion process is found to be feed-side, film- and membranediffusion controlled. The integral interdiffusion coefficient of counterions in the ion-exchange membrane are obtained from stirred cell data. An increase of interdiffusion activation energy with increasing bulk concentrations of nickel ion in feed solution is observed.View full abstractDownload PDF (543K) -
SHINICHI YUU, FUYUHIKO NAKAGAWA, HIROSHI MIHARA, YOSHIHIRO FUKUI1987 Volume 20 Issue 5 Pages 518-525
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSCollision efficiencies have been computed for unequal-size spherical particles settling in quiescent viscous liquids, taking into account the hydrodynamic interaction, interparticle attraction and electrostatic repulsion. The results are closely related to the mechanism of coagulation of colloidal particles in a sedimentation field. If the interparticle attraction and electrostatic repulsion are both negligibly small as compared to viscous drag, the collision efficiency η is very small, i.e. about 0.003. However, a relatively large Van der Waals force makes η greater than unity. As the ratio of the radii of the two particles (smaller divided by larger) decreases the collision efficiency also decreases. The repulsive force between particles determines whether the collision efficiency is zero or larger than zero, but it does not affect the magnitude of the collision efficiency. By including the effect of electrostatic repulsion we were able to develop criteria which determine the stability (or flocculation) of colloidal particles.View full abstractDownload PDF (578K) -
HITOSHI KOSUGE, TSUTOMU ISHIKAWA, KOICHI ASANO1987 Volume 20 Issue 5 Pages 525-530
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSNumerical approaches to ternary mass transfer in a laminar boundary layer were made by use of a laminar boundary layer theory considering the effects of interactions between diffusion fluxes and of mass injection or suction.
The effects of both the driving force ratios and the imilticomponent Schmidt numbers on the concentration profiles and the diffusion fluxes are discussed. A new correlation is proposed for the effect of the interactions between the diffusion fluxes under the condition of low mass flux and of zero tangential surface velocity, which is a function of the driving force ratios and the multicomponent Schmidt numbers. The possibih''ty of a reverse diffusion was also shown under the same condition. Some examples of numerical analysis are presented for the effect of mass injection or suction and of the tangential surface velocity on the diffusion fluxes.View full abstractDownload PDF (381K) -
Eizo SADA, SHIGEO KATOH, MASAAKI TERASHIMA, AZADEH KHEIROLOMOOM, HIROY ...1987 Volume 20 Issue 5 Pages 531-533
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSDownload PDF (242K) -
MIKIO KONNO, SHOZABURO SAITO1987 Volume 20 Issue 5 Pages 533-535
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSDownload PDF (203K) -
MOMPEI SHIRATO, TOSHIRO MURASE, EIJI IRITANI, SHUJI NAKATSUKA1987 Volume 20 Issue 5 Pages 535-538
Published: October 20, 1987
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSDownload PDF (226K)
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