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Tohru Niida, Tetsuo Yoshida, Ryozo Hirata
1977 Volume 3 Issue 2 Pages
109-114
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Net flow rate of fluid through the clearance is estimated by a new model (Pressure-Balancing Model) which is based on the total balance of pressure changes both in sectors and in clearances throughout the annular space. Pressure gradient in the model is evaluated from the Couette-Poiseuille flow in both regions. It is revealed by the model that the estimation of the flow rate is affected by the gap width of the clearance, the radii ratio, the number of blades and their thickness. In the above model the effective thickness of the blade has been introduced to account for the effect of the shape of the blade tip and of the approximation of pressure gradient in the clearance.
From the experimental results, the assumption of the Couette-Poiseuille flow has been confirmed in the velocity profile and in the flow rate; for the velocity, the agreement between observation and theory has been well shown in Fig. 7 with and without clearance, and for the net flow rate, Eq. (11) together with an appropriate blade thickness, that is, the effective thickness, may be used to predict successfully.
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Korekazu Ueyama, Terukatsu Miyauchi
1977 Volume 3 Issue 2 Pages
115-121
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Bubble columns of 60 cmφ and 30 cmgφ diameter were used to investigate the effects of liquid viscosity and column diameter on the flow properties of mixed phases.
In the 60 cmφ bubble column, liquid viscosity was varied from 0.16 to 7.1 stokes, and the superficial velocity of gas was 3890 cm/sec. In the 30 cmφ bubble column, liquid viscosity was from 0.01 to 2.2 stokes, and the superficial velocity of gas was about 46 cm/sec.
The velocity of the internal circulating flow decreased with increase in liquid viscosity. The effect of the viscosity of a liquid on the behavior of the internal flow is discussed by use of previous theory of the internal circulating flow in a bubble column. Conclusions are as follows. 1. When the viscosity of liquid is less than about 2 stokes, the internal flow of liquid is a fully developed turbulent flow. 2. When a viscosity of liquid becomes larger than about 6 stokes, the effect of liquid viscosity on the internal flow of liquid becomes appreciable.
Radial distribution of the volume-surface average diameter of bubbles in a column has turned out to be classified into 5 groups which depend on liquid viscosity and column diameter, but not on superficial gas velocity.
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Akinori Matsuura, Takashi Akehata, Takashi Shirai
1977 Volume 3 Issue 2 Pages
122-126
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Friction pressure drops in air-water concurrent downflow were measured in a column, 8 cm in diameter, 40 cm in height, packed with glass spheres of 0.12, 0.26 and 0.43 cm.
A two-phase friction factor was defined by the equation
(Δ
P/Z)
t=4
ftρ
lul02/2
gcdp·1-ε/ε
3hφ
2where
h expresses total holdup and φ fraction of dynamic holdup to the total.
All the data were correlated well by an empirical equation of
ft=1.2×10
3Ret-1.1 (4<
Ret<10
3)
where
Ret=ρ
lul0dp/μ
l (1-ε) φ
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Sumitoshi Ogata, Yasuhiro Hara, Hisashi Shinohara
1977 Volume 3 Issue 2 Pages
127-131
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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The break-up mechanism of a liquid jet stretched out by electrostatic force were analyzed experimentally, in which both positive and negative dc voltages were applied to a fine metal capillary.
In relatively lower voltage regions, the break-up of the jet could be described by Schene's model, for the space charge effect in that voltage region was very weak. Corona discharge from the lower portion of the jet, however, became more marked with increasing voltage and caused the formation of strong space charge density. Moreover, space charge effect was found to be more pronounced in the negative dc case.
It was further found that under constant mass flow rate conditions there were optimal voltages to minimize mean particle diameter at which the atomization efficiency reached to a maximum of about 1 %.
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Sumitoshi Ogata, Takashi Hatae, Kazuo Shoguchi, Hisashi Shinohara
1977 Volume 3 Issue 2 Pages
132-136
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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The charge of the droplet generated by electrostatic atomization of liquids was measured for a variety of experimental conditions. Controlling variables on the specific charge were then analyzed.
The experimental equation of volume surface mean diameter
dvs could be derived by developing the result of specific charge analysis.
dvs/
D0=11.4 (
vμ
l/σ)
2/3 (ε
0/κσ/
D0μ
l)
2/9 (
V/√
D0σ/ε
0)
-10/9 (
L/
D0)
2/5The measurements of droplet size were performed under the following conditions with distilled water, glycerin-water solutions, ethanol and
n-propanol as the working fluid; applied voltage 9.0 to 17.5, mass flow rate 1.3 to 18 g/min, electrode separation 60 to 120 mm.
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Junjiro Kawasaki, Toshiki Hamatani, Nobuaki Nakazawa, Toyohiko Hayakaw ...
1977 Volume 3 Issue 2 Pages
137-141
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Transition from a stable flow to hammering in a horizontal cocurrent flow of steam and cold water was investigated and the following results were obtained.
Visual observation by high speed motion picture showed that hammering occurred (a) when the entrainment by the steam flow started, and (b) when the flow regime of the two-phase flow transited from stratified or wave flow to slug flow. The critical local velocities of steam were (a) 1740 m/sec, and (b) 7 11 m/sec, respectively. Mixing of a small amount of air into steam was practically effective in preventing the two-phase flow from hammering.
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Katsuyuki Kubota, Shinya Hayashi, Tsutomu Kondo
1977 Volume 3 Issue 2 Pages
142-148
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Cationic metallic ions, Na
+ and Cd
2+, were floated by using foam separation technique in a continuous flow system.
Experiments were carried out mainly on the conditions such that the pH range was limited within 1.3 to 4.0 and collector (sodium dodecylbenzenesulfonate, M.W. =348.48) concentration was stoichiometrically greater than that of the colligend (Cadmium). Surface excess of colligend was greatly influenced by the co-existing H
+ ion under constant concentration of collector and colligend ions within a pH range less than 4.0, and in turn, only slightly by the co-existing collector concentration under constant concentration of H
+ ion and colligend (pH =4.0). It was also established that a considerable difference between mono-and divalent cationic metallic ions for the affinity to neutralize the negatively charged surface on gas-liquid interface was observed and verified by use of Gouy-Chapman diffuse double-layer theory, except for high concentration range of the co-existing collector forming micellaneous metalcollector complexes.
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Ken Toyokura, Kenji Tawa, Yuzuru Wakabayashi
1977 Volume 3 Issue 2 Pages
149-153
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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New charts for design of continuous mixed crystallizers are devised from design equations proposed by the Authors under Δ
L law. These charts correlate nucleation rate, growth rate, product crystal size, suspension density and crystallization rate per unit volume of a crystallizer, and can be applied for easy design calculation of the volume of a crystallizer and the estimation of product size from pilot plant data of nucleation rate, growth rate and suspension density. Furthermore, the number of fine crystal required to be added or removed to produce the desired crystal size is readily obtained by these charts.
Bransom equations for crystal growth rate are discussed for design, and these charts are shown to be able to be applied under a little device. Additionally, new decision of power of crystal size in Branson equations is proposed. Design result from Bransom equations is compared with one from Δ
L, law for the same design conditions and data, and the difference between them is shown not to be negligible.
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Akira Yasunishi
1977 Volume 3 Issue 2 Pages
154-159
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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The effect of pH on the oxidation rate of aqueous sodium sulfite solution with cobaltous ion catalyst by oxygen was investigated by a gas absorption method at 25°C.
Measurements were made using solutions of 0.3 and 0.04 mol/
l of sodium sulfite with 10
-6 mol/
l of cobaltous ion in a region of pH values from 6 to 13.
The relation between the reaction rate and the pH value in solution was too complicated to correlate by a simple expression. Therefore graphical representations for these relationships were shown.
From these figures, it was proved that there was only a limited pH range where one can correlate the reaction rate with pH by simple expressions.
Some useful information was obtained from the observed results in applying the sulfite oxidation method to study the performance of gas-liquid contacting equipment.
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Yoshiki Goto, Hiroshi Ooi, Yoshio Harano, Tatsuya Imoto
1977 Volume 3 Issue 2 Pages
160-165
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Dispersed micro-cellulose in water was prepared by grinding filter paper for quantitative analysis with a ball mill for 55 hours and in the presence of water, and its coagulation and flocculation were studied, using aluminum sulphate as a coagulant.
The floc grows by the coalescence, in the initial stage of agitation, and then reaches a maximum value. The maximum average floc diameter, d
32 is correlated with the agitation rate, N, according to Shinnar's relation :
d32∝
N-3/4. Comparing the floc size distribution obtained microscopically with that obtained from the sedimentation curve on the basis of light transmission measurement, the average density of the floc (agitation 100 rpm, 10 min, at 25°C) is estimated to be 1.011.02 g/cm
3.
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Yasuhiko Tonooka, Ichiro Inoue, Yoshihide Mori
1977 Volume 3 Issue 2 Pages
166-171
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Radial mixing characteristics in turbulent flow of water near the center of a porous tube with circular cross section were experimentally studied. Water was injected uniformly through the tube wall at various ratios of mass velocity through the tube wall to the average mass velocity at the entrance cross section of the tube, ranging from 0.001 to 0.01. As the results of experiments, the values of the dispersion coefficient used as usual and the characteristic length was related with operational conditions by the method of measuring the stationary concentration distribution of tracer emitted continuously from a fixed point source at the center of the entrance cross section of the tube.
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Effects of incidence angle and deviation from Stokes drag
Kenichi Ushiki, Kiyokazu Kubo, Koichi Iinoya
1977 Volume 3 Issue 2 Pages
172-178
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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This paper gives calculated results of average and local impaction efficiencies for a ribbon having various angles of incidence to the flow direction and for particle Reynolds numbers from Stokes to Newton regions. Discontinuous potential flow is used around the ribbon for computation and is in good agreement with the observation for paraffin mist. The calculated efficiencies also agree well with the experimental results for licopodium spores.
The impaction efficiency decreases as the particle Reynolds number increases for Reynolds numbers beyond the Stokes region. And the impaction efficiency has good correlation with the apparent inertial parameter newly defined.
The smaller the inclination angle of a ribbon, the higher the impaction efficiency. This tendency is remarkable when Stokes drag is not applicable. The obtained distribution of local impaction efficiency is more uniform than that of existing theories. As the angle of incidence becomes smaller than 90 degree, the local impaction efficiencies are higher at the leading edge and lower at the trailing edge of the ribbon, but it changes little at the center line of ribbon.
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Noriaki Kubota, Shuzi Wakabayasi, Kenji Shimizu, Tadao Kawakami
1977 Volume 3 Issue 2 Pages
179-182
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Densities and viscosities of the solutions, respectively, were measured up to about 20°C and 15°C of subcooling.
Prior to the measurements, the solutions were filtered and kept higher than the saturation temperature. These treatments prevented the solutions from nucleation, and made the measurements possible, even in highly supersaturated states.
A set of equations are derived to calculate the density as a function of a given temperature and a saturation temperature of the solution.
Measured viscosities agree, even in the supersaturated region, with the values calculated by Tanaka's experimental equation which have been applied only to the undersaturated state.
It seems from these results that the supersaturated solution does not differ markedly from the undersaturated solution in structure.
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Akira Matsuda, Tsuyoshi Munakata, Hiroyuki Miyawaki, Toru Watanabe
1977 Volume 3 Issue 2 Pages
183-188
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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Vapor-liquid equilibria for three systems were measured at range of pressures from 100 to 5 mmHg. The systems are ethyl oxalate-methyl salicylate which is a nearly ideal solution, and dioxane-water and ethylbenzene-
n-butanol which are non-ideal solutions. Liquid was agitated by means of a magnetic stirrer or a propeller. A test for the thermodynamic consistency of the data was made by the Herington method. When liquid boiled at higher pressure or was agitated by means of the propeller, data were apt to be consistent thermodynamically. Also, it is shown that as nonideality of the test mixture increases the test promises consistency too readily.
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Kaichiro Wakabayashi, Shinkichi Yamaguchi, Toshitatsu Matsumoto, Tetsu ...
1977 Volume 3 Issue 2 Pages
189-194
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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From the results of experimental work on the characteristics of a fine particle bed composed of an equal mixture of Kibushi clay and feldspar, an analysis is made to determine the phenomena of the liquid moisture movement in such a fine particle bed. Based on a few assumptions of the liquid moisture movement in the bed, the fundamental equation is derived to describe the phenomena.
Comparing the results of the drying experiment with the solutions of the above equation, it is shown that the mechanism of the liquid moisture movement in the bed during the drying process can be explained by the present equation.
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Akihiro Yamanaka, Nobuo Mitsuishi
1977 Volume 3 Issue 2 Pages
195-199
Published: March 10, 1977
Released on J-STAGE: February 12, 2010
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Experiments have been carried out in the range of 1.0<
Npe<10
3, 1.6×10
-6<
NGr<0.44, 2.6×10
4<
Npr, < 6.4×10
5 and 0.24<
NGr1/ (n+1) Npr'2n/ (3n+1) <74, where
Npe is Péclet number, and
NGr and
Npr are generalized Grashof and Prandtl number for power-law fluids as defined by Acrivos, respectively. A sphere, 46.03 mm in diameter, composed of eleven copper segments, and two brass spheres (19.03 and 9.534 mm in diameter) have been used. Test liquids used are 2.61 %MC (methylcellulose), 5.52 %CMC, 0.74 %SPA (sodium polyacrylate) and 1.48 %PEO aqueous solutions. The experimental data are summarized by the following relation :
Nu
m-2= [(0.866σ
2/3Npe1/3-0.553σ-0.341)
3/2+ (0.44
NGr1/ (2n+2) Npr'n/ (3n+1) )
3/2]
2/3 (
Kb/
Ks)
1/ (3n+1) where
σ=-2.475
n3+6.738
n2-7.868
n+4.740
and
Kb and
Ks are the values of power-law model parameter
K at the bulk liquid temperature
tb and the sphere surface temperature
ts, respectively. This equation has been shown to represent measured values of
Nu
m, within an average deviation of 29.3 per cent.
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Toshiaki Yoshioka, Eiichi Kunugita
1977 Volume 3 Issue 2 Pages
200-204
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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It is possible to control a reaction rate in solution by adding rate enhancing solvent (solvent 2) such as a dipolar aprotic solvent to the feed which consists of reactant and solvent 1.
The addition of rate enhancing solvent increases reaction rate constant and it decreases inevitably the concentration of reactant in the reaction system. There may be, therefore, the optimum addition ratio of solvent 2 to the feed.
A graphical method to determine the optimum addition ratio of the solvent 2 was presented and was applied to saponification of ethyl benzoate and Hofmann reaction of bromo-benzamide in aqueous dimethyl sulfoxide and to hydrolysis of benzoyl chloride in aqueous acetone.
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Akio Nakayama, Megumu Yuzawa, Masanobu Hasatani, Sachio Sugiyama, Kazu ...
1977 Volume 3 Issue 2 Pages
205-217
Published: March 10, 1977
Released on J-STAGE: October 21, 2009
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1977 Volume 3 Issue 2 Pages
217a
Published: 1977
Released on J-STAGE: October 21, 2009
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1977 Volume 3 Issue 2 Pages
217b
Published: 1977
Released on J-STAGE: October 21, 2009
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1977 Volume 3 Issue 2 Pages
217c
Published: 1977
Released on J-STAGE: October 21, 2009
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