In this paper, we have investigated the process of the first stage (film state boiling) of rapid cooling due to quenching of high temperature body. The series of experiments were carried out keeping on the initial conditions of test body constant under the various conditions of cooling media. Arranging the data obtained by the experiment for 22 sorts of liquids used as cooling medium, the authors established an empirical formula shown as follows;
where α stands for heat transmission coefficient in cal/cmcm2sec°C, R the rdius of the specimen in cm, Δu₁=u_R-u₀°C, Δu₂=u₂-u₀°C, u_R surface temperature of a specimen, u₂ boiling temperature of cooling liquids, u₀ temperature of cooling liquids, and λ, σ, γ, c_p, ν and a are the same ones shown in table 1.
From eq. (2) they confirmed the following items.
1) Nusselt's Number αR/λ grows up with the increase of σ and a, whereas it decreases with the increase of γ and ν.
2) Slight variation of σ affeets considerablly Nusselt's Number.
3) The numerator of Δu/Δu₂ becomes a measure of the thickness of vapor film and Nu decreases with the rising of Δu₁ which is increased with the growth of film. The denominator Δu₂ is changed by the variation of u₂ and becomes a measure of influence of boiling temprature.

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定温における氣液平衡關係は古くから研究され,熱力學的に究明されているが,定壓における氣液平衡關係の熱力學はその重要性にもかゝわらず最近に至るまで研究されなかつた。著者らの1人はなかば經驗的に定壓における氣液平衡關係の基礎式を導き,その中に含まれる常數を文獻にある實測値によつて決定した。この報文では熱力學的にその基礎式を導き,その中に含まれる常數を他の物性常數から計算によつて求める方法を示そうと思う。なお以下において2成分系に對して得られる結論はそのまゝ多成分系に擴張できるものである。

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Combined with the formula of the bottom pressure in a column of powder, p=(B/4μ)^ρ_αp…(1), the author derived a simple equation of solid dischage rate through orifice from the experimental results with sand, quartz and active earth powder ranging 30-150 Mesh, and expressed it in a nomograph in Fig. 5. Vertical glass pipes of 1/2" and 1"φ were used as the apparatus, illustrated in Fig. 1, with orifices of 9.0, 8.15, 6.5, 6.3, 5.3, 4.0, 3.9 and 2.3mm. in diameters at the bottom of it. Combining the above equation with the general orifice equation u=c√2gΔh…(2), the author proposed the following equation, u=c√gB/2μ(cm/sec)…(3), or W=(π/4)cρ_αp√gB⁵/2μ(gr/sec)…(5).
The calculated values of the discharge coefficient from the experimental data, are about c=0.5-0.7, and c=0.6 on the average, similar to that in fluid orifice equation. The contracted flows were also observed.

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