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Volume 17, Issue 1
Displaying 1-18 of 18 articles from this issue
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PAILIN CHUCHOTTAWORN, AKIRA FUJINAMI, KOICHI ASANO1984 Volume 17 Issue 1 Pages 1-7
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSNumerical analyses for heat and mass transfer of a solid sphere without and with uniform, sinusoidal and evaporative mass injection or suction were made by use of a finite difference method for Rep = 1-200, Pr or Sc = 0.5-2 and φ= -0.2-0.5.
Numerical results for the case without mass injection or suction showed good agreement with the results of previous workers. Heat and mass transfer rates with uniform mass injection or suction were found to be affected by Rep and Pr or Sc as well as mass injection ratio, φ.
New correlations for the effect of mass injection or suction on heat and mass transfer rates for the case with uniform and sinusoidal mass injection or suction in terms of transfer number were proposed. Heat and mass transfer rates with sinusoidal mass injection or suction showed good agreement with those for evaporative mass injection or suction.View full abstractDownload PDF (498K) -
PAILIN CHUCHOTTAWORN, AKIRA FUJINAMI, KOICHI ASANO1984 Volume 17 Issue 1 Pages 7-13
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSExperimental studies on the rate of evaporation of a volatile, pendant liquid drop under high ambient temperature conditions (high mass flux) were carried out for the evaporation of water, methanol, n-hexane, n-pentane and carbon tetrachloride drops into dry air. Measurements were made for Rep = 32-328, Sc = 0.60-1.66 and dimensionless driving force B=0.02-1.36.
Experimental results for the rate of evaporation of a liquid drop under low ambient temperature conditions showed good agreement with the low-flux equation by Ranz and Marshall and also with previous numerical solutions. Experimental results for rate of evaporation under high ambient temperature conditions showed a systematic deviation from the Ranz-Marshall correlation.
Taking into account the effect of high mass flux together with the effect of variable properties, a new correlation equation was proposed which correlated all the experimental data very well.View full abstractDownload PDF (553K) -
ISAO MATSUI, DRAGOSLAV M. MISIC, MOTOYUKI SUZUKI1984 Volume 17 Issue 1 Pages 13-19
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThermogravimetric analysis was utilized to study kinetics of the activated carbon-steam reaction for five different carbons. The experimental results show that the heating rate of samples has very little effect on the values of the activation energy (E) and the reaction rate constant (K). The activation energy of gasification increases and passes through a maximum as the weight of a sample decreases, except for DARCO activated carbon. Initial rate of gasification increases with steam concentration for all the carbons. The calculated activation energies and initial reaction rate constants (k1073) were between 180 and 280kJ/mol, and 2.76 × 10-5 and 3.05 × 10-4s-1, respectively.View full abstractDownload PDF (420K) -
SHIGEHISA ENDOH, KENJI YAMAGUCHI1984 Volume 17 Issue 1 Pages 20-26
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSMullite beads (2.38-2.83 mm in diameter) whose shapes are irregular but close to spherical were repeatedly separated with an inclined rotary disk. The disk was tilted at 4.5° to the horizontal and rotated at 6.5 rpm. After 10 separations, the beads were finally classified into two groups: highly spherical particles and others. The shapes of these particle projections were analyzed and several linear discriminant functions (LDF) for particle shape were determined. The degree of sphericity and separation efficiency were evaluated and the effects of shape indices on the separation and discrimination were studied. Variances of sphericity between the classified groups of particles are larger than those of surface roughness and elongation. The shapes of mullite beads are satisfactorily discriminated with an LDF composed of two indices on global sphericity. The separation efficiency can also be evaluated by using the same LDF.View full abstractDownload PDF (524K) -
HAE YOUNG JUNG, WON-KYOO LEE1984 Volume 17 Issue 1 Pages 26-33
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA method is developed for on-line noninteracting control of a nonlinear multivariable process to handle constraints on the control variables based on the derivative decoupling control approach. An extension of the proposed modified derivative decoupling control method to load changes (unknown disturbance) is also treated. This modified method is investigated for noninteracting control of laboratory-scale mixing tanks in series both by digital simulation and by experiment using an on-line microcomputer. Liquid levels and temperature in tanks mixing hot and cold water inflow streams are controlled. The results are compared with those obtained by instantaneously optimal control and by the inverse Nyquist array technique. Both simulated and experimental performances of the modified derivative decoupling controller are found to be better in comparison with those obtained by the controller based on the inverse Nyquist array. Further, experiments showed that the modified derivative decoupling controller can reduce interaction to a negligible level.View full abstractDownload PDF (527K) -
TOSHIO KAJIUCHI, ATSUSHI SAITO1984 Volume 17 Issue 1 Pages 34-38
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSLaminar pulsating flow of a clay slurry in a circular pipe was studied experimentally. The flow behaviour of the slurry was approximated as that of a Bingham plastic fluid. The addition of sinusoidal pulsating fluctuation to a steady pressure gradient resulted in enhancement of the flow rate, because of the non-Newtonian behaviour of the slurry. The flow enhancement increased with the following conditions: (1) an increase in pulsating amplitude, (2) a decrease in pulsating frequency and (3) a decrease in the mean pressure gradient. The flow enhancement can be expressed as a function of three dimensionless groups: Stokes number for a Bingham plastic fluid, Bingham number and the pressure gradient ratio. An empirical correlation among these dimensionless numbers is presented. All experimental data could be closely correlated with respect to the flow enhancement.View full abstractDownload PDF (355K) -
TOMOSHIGE NITTA, TAKUO SHIGETOMI, MASAYUKI KURO-OKA, TAKASHI KATAYAMA1984 Volume 17 Issue 1 Pages 39-45
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSAn adsorption isotherm equation is derived from a localized monolayer model in which each molecule occupies multi-site on a homogeneous surface. The resultant expression is the same as that of Honig and Mueller (1962) for single-component adsorption derived from a fractional-sized vacancy model. An expression for multi-component adsorption is presented here.
The applicability of the adsorption equation is tested for systems of hydrocarbons and carbon dioxide on activated carbon, molecular sieving carbon 5A and Molecular Sieve 5A. Parameters determined from a best fit to single-component adsorption data are consistent with the physical properties of molecular sizes and the BET surface area of adsorbent. Adsorptions of binary mixtures are predicted fairly satisfactorily by use of the parameters obtained from single-component data.View full abstractDownload PDF (492K) -
TOMOSHIGE NITTA, MASAYUKI KURO-OKA, TAKASHI KATAYAMA1984 Volume 17 Issue 1 Pages 45-52
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSAn adsorption isotherm for a heterogeneous surface is described on the basis of a multi-site occupancy model followed by a group-contribution assumption. Equations of single- and multi-component adsorptions are derived for systems of molecules consisting of several functional groups and a surface composed of active sites of different energies interacting with the groups independently. The isotherm equation reduces to the expression derived by Sparnaay in the special case where a molecule occupies one site of the surface.
The theory is applied to adsorption equilibria for systems of oxygen, nitrogen, and carbon monoxide on Molecular Sieves 5A and 10X. Correlations of single-component isotherms are excellent for nitrogen and oxygen and fairly good for carbon monoxide; predictions of adsorption isotherms of binary gas mixtures are made satisfactorily by means of parameters determined from the best fit to each single-component isotherm.View full abstractDownload PDF (588K) -
AKIYOSHI SAKODA, MOTOYUKI SUZUKI1984 Volume 17 Issue 1 Pages 52-57
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSFundamental experiments on the solar-powered adsorption cooling system were carried out with small-scale apparatus simulating ideally a practical unit by employing a combination of silica-gel and water vapor as an example of the adsorbent-adsorbate combinations. A simple model which takes into account both adsorption properties and apparatus characteristics was proposed to interpret our experimental results quantitatively. Then the transitional behavior of heat and mass transfer in continuous adsorption-regeneration experiments was successfully interpreted by the model. The model proposed here is not a complete one and is to be considered as a first-step model for estimating operation with practical equipment. Also, the contribution of the level of regeneration temperature of adsorbents to the cooling performance was quantitatively clarified on the basis of the adsorption equilibrium relation, which is considered useful in choosing a favorable combination of adsorbent and adsorbate for the system.View full abstractDownload PDF (485K) -
SON-KI IHM, IN-HWAN OH1984 Volume 17 Issue 1 Pages 58-64
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSSucrose inversion was carried out in a batch reactor, using two types of macroreticular resin catalyst (Amberlyst 15 and Amberlyst XN-1010). Experimental data were obtained to determine the effect of particle size, reaction temperature and resin amount on the initial reaction rates. A two-phase model, proposed by the authors, was applied to elucidate the interaction between reaction and diffusion inside the resin particle. The present reaction is of first order and the overall effectiveness factor can be expressed analytically in terms of the pore- and the microparticle effectiveness factors together with the fraction of active acidic sites exposed to the pore space. The experimental data were in excellent correlation with the proposed model.View full abstractDownload PDF (501K) -
KAZUNARI OHGAKI, TAKASHI KATAYAMA1984 Volume 17 Issue 1 Pages 65-70
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSA simple molecular model is proposed for prediction of second virial coefficients of linear symmetric molecules. The intermodular potential is substituted by summation of the group-group interactions described by the Lennard-Jones 12-6 potential.
The second virial coefficients of oxygen, carbon dioxide and ethylene predicted in the present study agree with the recommended values of IUPAC within 1% or 1cm3 mol-1 for wide temperature ranges. Furthermore, the prediction method proposed is compared with the intermodular potential model of Lennard-Jones and the corresponding state theory of Tsonopoulos.
The present model is extended to mixtures straightforwardly without any binary parameter. The interaction second virial coefficients predicted by the model are in good agreement with observed data.View full abstractDownload PDF (422K) -
ZHENG-LAN ZONG, XI-HAO YANG, XI-YIN ZHENG1984 Volume 17 Issue 1 Pages 71-78
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSAn empirical equation is proposed for correlating vapor-liquid equilibrium data of alcohol-hydrocarbon, alcohol-alcohol and alcohol aqueous solutions. It shows a slightly better fitting accuracy than a modified Wilson, NRTL and UNIQUAC equation.
The posibility of correlating pair parameters is also investigated.View full abstractDownload PDF (501K) -
KUNIO KATO, DAISUKE TANEDA, YUKINORI SATO, MANEI MAA1984 Volume 17 Issue 1 Pages 78-82
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSThe lateral mixing of fluidized particles in a packed fluidized bed with cylindrical screen packings was investigated from the unsteady state behavior of tracer particles. The tracer particles were activated alumina particles on which zinc acetate was adsorbed. The lateral mixing characteristics were analyzed by a diffusion model. The lateral dispersion coefficient of the particles was strongly affected by packing size, fluidized gas velocity, and the minimum fluidized gas velocity of the particles. An empirical equation for the lateral dispersion coefficient of the particles in a packed fluidized bed with cylindrical screen packings was obtained.View full abstractDownload PDF (325K) -
TOSHIKUNI YONEMOTO, TEIRIKI TADAKI1984 Volume 17 Issue 1 Pages 83-88
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSConvective sublimation from a cylinder fixed in a parallel-plate duct has been studied, both theoretically and experimentally. In the theory, a simple and efficient finite difference technique has been developed to solve the Navier-Stokes and diffusion equations. The procedure contains a transformation of the coordinate system to facilitate the treatment for curved boundaries. The calculated results concerning the average Sherwood number are in very close agreement with those of the experiment.
Through a comparison of the results for bounded flow in a duct with those for unbounded flow in an infinite region, it is found that the duct wall tends to depress the development of the wake behind a cylinder, and to promote mass transfer from it.View full abstractDownload PDF (401K) -
MICHIAKI MATSUMOTO, KAZUHARU YOSHIZUKA, KAZUO KONDO, FUMIYUKI NAKASHIO1984 Volume 17 Issue 1 Pages 89-93
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSMeasurements of the extraction equilibria of copper and zinc with N-8-quinolsulfonamides dissolved in toluene were carried out at 303 K.
It was found that the extractants (HR) exist as monomers and that copper and zinc (M) form a complex of an MR2 type in toluene diluent with HR.
Frorti the experimental results, it is seen that extraction constants of alkaryl-substituted N-8-quinolylsulfonamides are larger than those of alkyl-substituted N-8-quinolylsulfonaniides.View full abstractDownload PDF (344K) -
MASAKUNI MATSUOKA1984 Volume 17 Issue 1 Pages 93-99
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSSolid condensation of naphthalene vapors onto a cold surface was observed, and the rate of condensation was analyzed by use of an equation that included rates of nucleation and growth of the nuclei. Photographs of the condensation process taken at definite time intervals were analyzed with a digital image processing system to compute the nucleation rates, rates of increase in crystalline areas and the perimeters of the crystals to provide correlations as functions of the supersaturation. The critical point observed in the plots of condensation rates vs. supersaturation was explained as the changes in the nucleation rate and the shapes of the condensates at that point. From the equations developed and the correlations, the volume growth rates of the crystalline particles were found to be proportional to the supersaturation.View full abstractDownload PDF (572K) -
SHIGENOBU TANAKA, TAKASHI FUKUDA, AKIO NISHIWAKI, YASUO KATO1984 Volume 17 Issue 1 Pages 99-101
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSDownload PDF (234K) -
HIROTSUGU HATTORI, ATSURO KOBAYASHI, IWAO AIBA, TETSUYA KODA1984 Volume 17 Issue 1 Pages 102-103
Published: February 20, 1984
Released on J-STAGE: April 19, 2006
JOURNAL FREE ACCESSDownload PDF (140K)
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