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Volume 9 (1983)
- Issue 6 Pages 603-
- Issue 5 Pages 477-
- Issue 4 Pages 353-
- Issue 3 Pages 233-
- Issue 2 Pages 111-
- Issue 1 Pages 1-
Predecessor
Volume 9, Issue 4
Displaying 1-17 of 17 articles from this issue
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Masatoshi Minamizawa, Kazuo Endoh1983 Volume 9 Issue 4 Pages 353-358
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe instantaneous fluid forces on a circular cylinder oscillating sinusoidally in viscous liquid were measured. Data were reduced by the method of Fourier analysis to obtain the average values of the added mass and drag coefficients over a cycle of oscillation and their relations to ocsillatory conditions were studied experimentally.
1) The drag coefficient was correlated with the Reynolds number of oscillation, aωd/ν, and the amplitude ratio, a/d, where a is amplitude, ω is angular frequency, d is diameter of cylinder and ν is kinematic viscosity. An empirical equation for the drag coefficient was deduced in a range of Reynolds number of oscillation from 1 to 20.
2) The added mass coefficient was correlated with the modified Reynolds number dd2ω/ν and a/d. when modified Reynolds number dd2ω/ν was comparatively small, experimental values for the added mass coefficient agreed well with the theory given by Stokes. The value of modified Reynolds number, where added mass coefficient began to deviate from theory, varied with a/d and had a minimum value around a/d=2.
3) When aωd/ν was large enough, the added mass and drag coefficients had a minimum and maximum, respectively, around a/d=2. For smaller a/d, the added mass coefficient had values of about unity as predicted by potential flow theory. At a larger value of aωd/ν and a smaller a/d, quasi-steady state theory was applicable to the estimation of fluid force at each phase of oscillation, because inertial force due to added mass becomes larger than the drag force.View full abstractDownload PDF (1148K) -
Yoshiro Inoue, Satoshi Akutagawa, Shuji Saeki, Ryuzo Ito1983 Volume 9 Issue 4 Pages 359-369
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe effects of ionic migration in electrolytic solution on stability, mass transfer rate and flow pattern in Benard convection in an electric field were studied experimentally and theoretically.
The concentration difference caused by Cu2+ deposition on copper cathode in H2SO4 solution forms an unstable stratified fluid layer and induces Benard convection. By measuring the electric current through the fluid layer, the unsteady behavior of average mass transfer rate was followed from initial static state to final steady convection state. The average Sherwood number at steady state is always larger than the Nusselt number in the corresponding heat transfer system. Therefore, it is concluded that ionic migration effects enhance mass transfer rate. The relationship between wave number and Rayleigh number, and the orbital direction in the hexagonal cell are different from those in the thermal system. Theoretical analysis by the energy integral method has confirmed that the effects of ionic migration make the electrolytic system unstable, decrease the critical Rayleigh number, and increase the average Sherwood number.View full abstractDownload PDF (4096K) -
Kazutoshi Kamiyanagi, Shintaro Furusaki1983 Volume 9 Issue 4 Pages 370-375
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSAn analytical method is proposed to obtain intraparticle diffusion coefficient, partition coefficient and longitudinal diffusivity from data of gel chromatography by modifying the theory of Ostergaard (1969). Its accuracy is investigated and compared with that by moment analysis. The accuracy of the two methods are found to be comparable. Impulse response curves are calculated by the use of the Fourier analysis using thus obtained parameters. The calculated curves agree well with the experimental results.View full abstractDownload PDF (814K) -
Liquid flow pattern and pressure distributionOsamu Miyatake, Toshiyuki Hashimoto, Chikara Miyata1983 Volume 9 Issue 4 Pages 376-382
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSIn an attempt to reach a quantitative understanding of the interaction between liquid flow pattern and flash evaporation, a numerical analysis was made, as a first step, of the twodimensional turbulent flow of liquid in a 1 m-long flash chamber with and without baffle plates by means of a finite difference procedure.
The results are presented primarily in the form of computer-plotted contour maps of stream function and pressure (i. e. saturation temperature) for liquid flow rates of 4.3×105 to 8.7×105 kg/h·m-width and standard liquid level of 0.4m.
Velocity and pressure distributions and flow patterns obtained by numerical analysis are found to be in reasonably good agreement with experimental or observed results.View full abstractDownload PDF (2755K) -
Relation between liquid flow pattern and non-equilibriumOsamu Miyatake, Toshiyuki Hashimoto, Chikara Miyata1983 Volume 9 Issue 4 Pages 383-388
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSBased on the numerical solutions presented in a previous paper for the flow pattern and pressure distribution in the isothermal turbulent flow of liquid in a short flash chamber with a vertical baffle plate, a numerical analysis was performed to predict the non-equilibrium temperature difference at flash chamber exit.
The effects of liquid temperature, liquid flow-rate, superheat, and height and location of the baffle plate on the non-equilibrium temperature difference were evaluated.
Experiments were also performed with a three-stage flash rig over the range of variables typical for multi-stage flash evaporator operation.
The numerical results compared favorably with the experimental results except for the extreme case where a split in the liquid was observed behind the top of the baffle plate. This numerical analysis may provide a useful design tool for characterizing new flash chamber configurations.View full abstractDownload PDF (1214K) -
Ikuo Yamada, Soo Gak Lee, Setsuro Hiraoka1983 Volume 9 Issue 4 Pages 389-395
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA rigorous method, as characterized below, is proposed to solve the design problem of doublet separation of the multicomponent distillation process.
1) A new plate-to-plate method is used by considering both the Murphree plate efficiency and variable molar rates of vapor and liquid in each section of the column.
2) For the determination of optimum feed plate the same manner as in Murdoch and Holland's method is used.
3) By considering an extremely small molar rate of nondistributed component in distil- late and bottoms within an allowable significant figure of the computer used, the condition of platematching is provided accurately for all components.
The superiority of the proposed method compared to the modified Waterman's method is demonstrated by numerical examples of the quaternary doublet separation of nC8-nC7-nC6-nC5 system.View full abstractDownload PDF (1114K) -
Ikuho Yamada, Bing Quan Zhang, Masatoshi Sawada, Soo Gak Lee, Setsuro ...1983 Volume 9 Issue 4 Pages 396-403
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA numerical method is proposed to solve the minimum reflux problem of multicomponent distillation for the operation type, considering the variable molar rates of vapor and liquid throughout the column. In this method the concept of hypothetical pinch plate and two convergenoe loops by means of the normalized θ's method are used to obtain the composition profile in the column.
The practical usefulness of the proposed method is illustrated by two numerical examples with the important conclusion that the value of minimum reflux ratio evaluated by the proposed method is larger than that by the well-known Underwood method.
It is found that, from the point of view of energy savings in distillation, in which the operational reflux ratio used tends to approach the minimum reflux ratio, the evaluation based on Underwood's minimum reflux ratio produces unsatisfactory results due to underestimation.View full abstractDownload PDF (1205K) -
Eiichi Oosawa1983 Volume 9 Issue 4 Pages 404-408
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSOxygen dissolves into water from dispersed bubbles and the water surface in a diffused aeration tank. The water surface can be divided into two regions, free surface and surface of bubble-bursting region. The bubble-bursting region is formed at the water surface above the gas diffuser. To evaluate the oxygen transfer rates of the three routes, oxygen concentrations at dynamic equilibrium were measured when nitrogen and air were used as diffused gas and gas on the free surface, in addition to measuring KLa as usual.
By experiment, where (width of tank) / (depth of water) =2, the following results were obtained.
1) The ratio of oxygen transfer rate from diffused bubbles to total oxygen transfer rate increases when diffused gas flow rate increases, and it is independent of tank scale.
2) Oxygen transfer coefficient in liquid phase at free surface is smaller by about one order of magnitude than that around diffused bubbles.View full abstractDownload PDF (986K) -
Katsuroku Takahashi, Fujio Ohtsubo, Hiroshi Takeuchi1983 Volume 9 Issue 4 Pages 409-415
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe extraction of copper from aqueous solution of copper sulfate by the (W/O) /W emulsion type liquid membrane was studied by use of an agitated vessel. The liquid membrane consisted of LIX65N-kerosene solution containing Span-80 as emulsifying agent, and the inner water phase was an aqueous solution of sulfuric acid. The breakage rate of the liquid membrane increased with LIX concentration, and was predicted by use of the pH value of the outer aqueous solution and the extracted fraction of copper. By taking into account the breakage, the extraction rate was calculated under the assumption that the reaction rate at the interface was the controlling step. Calculate extraction rates were in good agreement with experimental results when the effect of emulsifying agent on reaction rate was evaluated with the concentration of agent per unit interfacial area.View full abstractDownload PDF (1134K) -
Syouji Hirota, Keisuke Fukui, Masamoto Nakajima1983 Volume 9 Issue 4 Pages 416-420
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSIn a previous paper, a design method for the classifying crystallizer based on the assumption that crystal growth rate was n-th order (2≥n≥1) with respect to supersaturation was reported.
The validity of this calculation method for constant void type crystallizer was confirmed in the present work, using operating data from a CEC-type commercial plant.
A simplified design method for a constant-void crystallizer is also proposed and design diagrams are presented.View full abstractDownload PDF (683K) -
Mitsutaka Kawamura1983 Volume 9 Issue 4 Pages 421-426
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe pyrolitic rate equation for municipal solid wastes expressed in terms of C, H, O element composition as variables was tentatively examined as one of the trials to describe the rate equation of pyrolysis of municipal solid wastes. Papers from municipal wastes were classified with a semi-wet selective pulverizer and were ground to a size under 76μm. The pyrolytic experiments were performed under an inert atmosphere to observe the time change of element compositions of the pyrolytic process. A random-breakage model was applied to the analysis of this study.
A model based upon the assumption that the wastes had a uniform bond frame structure could well explain the pyrolytic process except for the initial period of pyrolysis if experimental functions to describe change rates of C-H bond and C-O bond density in the frame structure are introduced.View full abstractDownload PDF (951K) -
Nobuyuki Fujii, Yukihiro Shimazaki, Koetsu Ikeda, Hajime Miyama1983 Volume 9 Issue 4 Pages 427-433
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSChemical kinetics of photo-induced graft copolymerization of methoxypolyethyleneglycol methacrylate (SM) and N, N-dimethylaminoethyl methacrylate (DAEM) to dithiocarbamated polyvinyl chloride (DTC-PVC) was studied.
The photo-graft copolymerization in a batch reactor was carried out and the concentration of SM, DAEM and graft polymer were followed experimentally. Quantum yield of photolysis of DTC group, kinetic parameters for polymerization of SM or DAEM, monomer reactivity ratio and φ factor for copolymerization of SM and DAEM were determined independently.
Simulation of the graft copolymerization process was performed by substituting those parameters into the equations of photo-graft copolymerization. The simulation well explained the experimental results, especially at low conversion.View full abstractDownload PDF (1057K) -
Naotsugu Ito, Kenzaburo Obata, Toshikatsu Hakuta, Hiroshi Yoshitome1983 Volume 9 Issue 4 Pages 434-440
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSEquations were derived for determining the kinetic parameters (Z, E, n) and heat of reaction ΔH with respect to the consecutive thermal decomposition of solid by using the simultaneous DTA-TGA technique, and the theoretical DTA and TGA curves were predicted by integrating the equations numerically with varying input parameters.
As a result, for evaluating the heat of decomposition from the DTA peak, it was evident that the error in measuring the DTA peak area becomes large with increase in the degree of heat capacity changes of the sample and the value of cp1/|ΔH1|, which lead to large changes on the imaginary base line. On the other hand, it was found that the kinetic parameters can be obtained by analyzing the TGA curve directly.View full abstractDownload PDF (1093K) -
Kazuho Tamano1983 Volume 9 Issue 4 Pages 441-447
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA simple automatic system of measuring liquid particle size distribution has been deve loped. The system was attached to a microcomputer exclusively used as a convenient method of measuring liquid particle size.
This system, of a front-end computer and a host computer, is based on the distributed multi-processor system. The front-end computer gets the peak value of an impulse from a measuring circuit, calculates the value of the particle size and displays it. The host computer calculates and displays the size distribution using data transported from the front-end computer. By this method, liquid particle size is measured in real time, and size distribution is displayed promptly.
To check the system, the size distributions of water droplets of from 52 to 2300μm in size produced by a spinning-disk atomizer and the mist produced by a pressure nozzle were measured. The results of this measurement showed that the measured sizes using this method agreed with the results obtained by the immersion liquid method.View full abstractDownload PDF (5017K) -
Harumi Matsuzaki, Sankichi Takahashi, Hong Li Zhu, Yoshitaka Oguri1983 Volume 9 Issue 4 Pages 448-454
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSEffects of environmental factors (DO level, MLSS conc., etc.) on the kinetics of activated sludge have been studied by using a shaft-type aeration tank of 10m depth.
It was clarified that specific oxygen consumption rate, γ, is constant when DO level is greater than the critical DO and decreases when DO level is less than the critical DO. The critical DO, which has different values according to the dominant process in activated sludge, is 1.1-1.35mg/l in oxidation reaction and is 0.65-0.9mg/l in growth reaction. SVI is constant when DO level is greater than the critical DO and increases when it is less than the critical DO. When MLSS and retention time, TR, are constant, γ is proportional to specific COD removal rate, β. Dominant process in activated sludge varies with variation of MLSS or TR. Oxidation proceeds mainly when MLSS×TR is greater than 17000h·mg/l and DO level is greater than 4.5mg/l. Groth reaction dominates when MLSS ×TR is less than 10000 h·mg/l.
It is shown that βc with only a bacterium is greater than βc in mixture phase microorganism.View full abstractDownload PDF (3079K) -
Teruyuki Nagamune, Isao Endo, Ichiro Inoue1983 Volume 9 Issue 4 Pages 455-461
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSImpulse responses of specific rate of glucose consumption of a brewer's yeast (S. cerevisiae) v, that of cellular growth μ and that of alcohol production π to a pulse-feed of substrate were elucidated. By varying the concentration of glucose in the pulse-feed of substrate, the authors added the substrate to the system at different stages of batch cultivation and measured the changes in specific rates of the yeast cells.
The experiments showed that the responses of the specific rates were classified into two types according to the magnitude of increment in glucose concentration, ΔG. When ΔG was less than critical value ΔGc, the specific rates were not influenced by the pulse-feed of substrate. On the other hand, when ΔG was greater than ΔGc, the specific rates of the yeast cells were decreased immediately and it took some hours before the specific rates reached their maximum speed. The authors have obtained a relationship between ΔGc and a set of (G (τ-), X (τ-)), which indicate the concentration of glucose and that of cell mass at the time of substrate addition.View full abstractDownload PDF (1202K) -
Yasuhide Nishi, Kozaburo Ueda, Masahiro Fukuok, Naoya Yoshioka, Tadash ...1983 Volume 9 Issue 4 Pages 462-475
Published: July 10, 1983
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSDownload PDF (3456K)
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