It is found that differences between the gas-film resistances in the evaporation of pure liquid and in the physical absorption reported by Surosky-Dodge and Houston-Walker are inversely proportional to the liquor rate and the former is corresponding to the latter at the infinite liquor rate. The gas-film coefficients thus obtained may be expressed by the equation,
Comparison of this equation and a few equations previously presented is shown in Fig. 7a, and it appears that the effect of the liquor rate on the gas-film coefficient is nearly the same order of the results of Whitney and Vivian.
Using the over-all coefficients for sulfur dioxide absorption obtained by Whitney-Vivian and the gas-film coefficients calculated from the above equation, the liquid-film coefficients are calculated and correlated as follows:
This liquid-film coefficients are 30-35% lower than those predicted from the Sherwood-Holloway equation over the range of the liquor rate usually encountered, and are slightly higher than those calculated from the van Krevelen-Hoftijzer and the Scheibel-Othmer equation as shown in Fig. 7b.
These equations derived here are yet far from the general applicability. They, however, are only applicable to 1″ Raschig ring packings over the range of 500-10, 000lb./sq.ft.hr of liquor rates and 100-600lb./sq.ft.hr. of gas rates. Figs. 6a and 6b show the comparison of the observed and calculated over-all coefficients.

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When a red heated body was quenched into any cooling liquid, the body would cool through three processes, namely film state boiling, bubble state boiling and natural convection.
In our previous papers cooling phenomena by film state boiling due to quenching from high temperature were biscussed. Now in this paper we intend to report the results of investigation for the process of two stages, bubble state boiling and natural convection. The series of experiments were carried out keeping all the initial condition of a test body constant under the various conditions of cooling media.
Arranging the data of the experiments we came to the following conclusions.
(1) In the process of bubble state boiling the values of transfer coefficient are dominated by the initial temperature u₀ and the boiling temperaturet u₂ of coolants, and our experimental data can be generally put into order by using the equation (1) which shows that they are not influenced by the physical properties of coolants.
(2) A transition point appears as soon as cooling phenomena changes from boilling state to that of natural convection. The more the coolant is deairated, the more the transition point appears at hight temperature, and the much the coolant has air and gas, the more the point appears at low temperature.
(3) In the natural convection process, the coefficient α rises up according to the increasing of temperature of cooling liquid and if the temperature is increased over a limit, the coefficient α shows its decreasing. The coefficient α is greatly controled by Gr number as shown in the equation (2) and the smaller the viscosity ν is, the more the coefficient α is developed, in addition, it was confirmed by this experiment that the coefficient α raises itself easily, according to decreasing of the value of surface tension σ. Δu₁=u_R-u₀, Δu₂=u₂-u₀, u_R=surface temperature of test body (°C): Nu=Nusselt Number, Pr=Prandtl Number, Gr=Grashof Number, γ=specific weight of coolant (gr/cm3), R=radius of test body (cylinder) (cm)

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The authors intend to report in the present paper the results of investigation as to the process of the latter stage of rapid cooling, the bubble state boiling and natural convection due to quenching of a red heated body. The series of experiments were carried out keeping the conditions of coolants constant in spite of the variations of conditions of a body.
Variety of the conditions was excecuted by changing the initial temperature, surface smoothness or diameter of the test cylinder. Arranging the data of the experiments the authors came to the next conclusion.
(1) Bubble State Boiling
The points indicating the max. value, ..max of heat transmission coefficient appear 10-20. higher than the boiling points of coolants, notwithstanding the degree of smoothness of the cooling surface. The higher the quenching temperature and the more rought the conditition of surface is, the larger the ..max value is. .. values at the period of bubble-state boiling are put into order by arranging in the equation (1), so far as the condition of surface is not too rough.
(2) Transition Point
The transition point appearing at the moment when cooling phenomena change from boiling state to that of natural convection exists close to the boiling point of a coolant, in spite of the variation of initial temperature and the diameter of test cylinder. But the temperature for the transition point is lower than the boiling point as the condition of surface is much more rough .
(3) Natural Convection
The decreasing of the quenching temperature or the smoothness of the surface lowers the value of ... Authors could not confirm how the value of .. is influenced by the size of test cylinder
In the equation (1):
Δu=u_R-u₀, Δu₂=u₂-u₀, u_R=surface temperature of test bady (°C), u₂=boiling point of coolant (°C), u₀=initial temperature of coolant (°C)

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