Heat transfer between the fluidized solid bed and the tube wall is important in designing reaction vessels. This report shows some studies on heat transfer in fluidized beds. In §1, some solid particles, same in diameter but different in density, were used as fluidized solid, and variation of heat transfer film coefficient under the influence of air velocity was measured.
Tendency of heat transfer coefficient was found to depend mostly on the following conditions-transition state, fluidized beds and transportation. It was observed that the fluidized state, independent of either solid density or particle diameter etc., counted most in heat transfer coefficient. In §1, a fluidizing tube of somewhat larger diameter was used to decrease slugging motion and to measure horizontal temperature distribution; and heat transfer coefficient was measured using different kinds of solid particles.
An empirical formula for calculating heat transfer coefficient of fluidized beds is as follows:
For notation, refer to table 3.

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In experimental operation, it is often difficult to maintain a constant temperature throughout a flow reactor or during entire cycle of operation of a batch reactor. Under such non-isothermal conditions, satisfactory results can be obtained by calculating either the equivalent volume of the reactor which at a constant reference temperature would produce the same conversion as the original reactor, or its average effective temperature. Both the concepts are discussed.
For a number of cases where the temperature variation can be expressed as a relatively simple mathematical function of reactor volume, the pertinent integrals are evaluated. Eq. (27) and Fig. 4 are accepted for linear relation, Eq. (33), (34) and Fig. 5 for exponential, Eq. (37), (38) in the case where the reciprocal of temperature-volume is linear, and Eq. (43)-(51) for polynominal.
Examples are given of the application of the results to specific problems.

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The pressure loss of gas flow was measured in two kinds of wetted wall towers. The smallertower was made of glass and the other larger one of galvanized iron sheet. The gas used was air and the liquids were water, soap solution and glycerin solution.
The curves f vs. Re_G were concave upwards and f increased rapidly with the decrease of Re_G.This inclination became more significant when Re_L was large.
When as in eqs. (3) and (4), f_r and Re_Gr were defined in relation to the gas velocity relativeto the surface velocity of falling liquid film which was calculated from the theoretical equation by Nusselt, the curves f_r vs. Re_Gr were almost parallel to the curve for the dry wall tower. Itappeared that the surface of liquid was influenced by the roughness of dry wall when the film wasthin.
f_r was represented by the following equation:
f_r/f₀=1+3.97×10^-3(Re_L)^0.475(μ_G/μ_L)^-0.271.
From these results the surface of liquid may be likened to the rough wall of the 1st kind ("rauhe Wandung") when L and G are small and to that of the 2nd kind ("wellige Wandung") when L and G are large.
In the previous works reported by Gilliland et al. and Jackson et al. it was concluded that the surface of falling liquid film was the same as the surface of a fixed smooth pipe or that of a smooth pipe moving downwards with the surface velocity of liquid. From our results, however, it is probable that the above conclusion might prove wrong.

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Experiments on air-jet air driven pumps were made. In thebeginning, tests were performed for selecting the best form out of six kinds of diffuser inlets as shown in Fig. 5, for deciding theoptimum distance from the nozzle outlet to the inlet of the diffuser throat and for seeking the bestlength of the diffuser throat. The results are shown in Figs. 7, 8 and 9.
Then, the relations between p₁, p₂, p_d G₁ and G₂ were measured in detail, concerning each of 22 kinds of nozzles in combination with the H type difiuser inlet, under the condition in which the diffuser throat was 36mm long, and the distance from the nozzle outlet to the inlet of diffuser throat was 30mm.
Theoretical analysis, on the other hand, were made concerning the characteristics of an ejector model as shown in Fig. 6.
Eqs. (24) and (25)' resulted in a one-dimensional method of analysis. Eqs. (27) and.(28) were obtained from eqs. (24) and (25)', by giving the proper numerical values to some constants for the air-jet air driven pumps.
The comparison between experimental and analytical resultsshowed good agreement between them over a wide range of variables, as shown in Fig. 10.
It was further revealed concerning steam ejectors, that the results of calculation by using Eqs. (24) and (25)' were in good accord with Hayami's data, as shown in Fig. 13.
The method of deciding the optimum area ratio aopt. from eqs. (27) and (28)' is presented in Fig. 12.

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