Experiments were made on vaporization of water into air stream in a wetted wall tower. Pressure loss of air, rate of heat transfer, rate of mass transfer and velocity-, temperature- and humidity profiles were measured. As a result it was found that a wetted wall tower must not be treated as the same as a smooth pipe and the values of coefficients of rate of transfer in vapour phase only become greater than those previously reported. Moreover we calculated the values of coefficients of eddy diffusion for fluid friction, heat transfer and mass transfer, and by comparing them we gained the proportional relation among transfer phenomena instead of the analogous relation which has been postulated. Proportionality seems to be varied with boundary conditions, but the physical meaning of this relation is still unknown.

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Concerning the calculation of the simultaneous transfer process of heat and material, such as humidification, dehumidification or water-cooling, a method to use the enthalpy difference has been advocated recently. This method is based on some assumptions, postulating the applicability of Lewis' law, the approximate heat balance and that the humid heat in main stream of air is nearly equal to that in interface. In some cases, however, these assumptions come to be far from permissible, resulting in considerable deviations.
Based on less assumptions than those which were ever made, the author proposed a more general method, which bears a more comprehensive applicability and secures more precise results in these calculations.

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Although there are several empirical formulas for pressure drops in transfer line of pneumatic conveyor, their results are not always coincident with experimental data. Some powders whose specific weights are not equal but general properties are nealy equal give more excessive pressure drops in transfer line than by previous formulas. Under these circumstances, following empirical fermula express actual results more exactly. where;
λ: Friction factor for the solid particles.
v: Mean air velocity, m/s
γ: Particle specific weight
K: Solids air Mixture ratio
B, c, a, b, n: Empirical comstants

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Percentage humidity φ=y/y_s and relative humidity ψ=H/H_s have both been very popularized for us. But their physical meanings are limited to the lower temperature range than the temperature at which the saturated vapor pressure is equal to the total pressure of the system. For example, in the case of air-water system at 760mmHg total pressure above 100°C, φ must be given a suspicious value as the quotient of p divided by a greater pressure than 760mmHg which is the total pressure of the system, and therefore it may happen that the value of p is greater than the total pressure 760mmHg. In that case, ψ may become a negative and meaningless value. The fact that the value of H is infinity having no relation to the value of ψ at 100°C, is disagreeable for us.
The authers propose a new definition to represent the humidity % as follows: then
above 100°C and they name ε "Specific humidity, " temporarily.
The advantages obtained by using this specific humidity ε in place of ψ or φ are as follows:
(1) We can represent and treat numerically any condition of humidity % without limitation of temperature range, rationally.
(2) The condition of ε=100% is correspond to ψ=100%, and the replacement of or ψ by in Carrier's type humidity chart brings no obstacle to other relations.
(3) It is possible to convert the value of humidity % between dry basis H and wet basis ε=H/(1+H), on th ordinate H scale of the Carrier's type chart.
Fig. 1 & 3 are the skeleton of such a humidity chart, and Fig. 2 & 4 shows the relation between ε and ψ at various temperatures.
The matter in this report will hold in any other system of gas-vapor mixture.

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Assuming that carbon is consumed in a gas producer with airsteam blast in three ways: C+O₂→CO₂, C+CO₂→2CO, and C+H₂O→CO+H₂, the method for calculating the composition of gases in the fuel bed with the aid of HRU (Height of reaction unit) was proposed.
Furthermor, basing on our equations, the relation between the saturation temperature of blast and mean temperature of reaction zone in the producer was determined from the Wada's experimental results.

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