51. T. Mivake : Miscellaneous Experiment Concerning the Artificial 

 Dissipation of Fog 



The preliminary experiments on the method of artificial dissipation 

 of fog such as by means of an absorbent, a wire-netting, heating and 

 watering, &c., were performed to investigate to what extent these methods 

 were effective. 



.32. /. Yoshida, T. Takano, and D. Kuroiwa : Preliminary Investigation 

 on the Thermal and Electrical Dissipation of Fog 



A fundamental experiment was performed to find out the amount 

 •of heat necessary for the dissipation of fog by electric heating and by 

 hot air produced b}' combustion. Further, on the basis of the principle 

 of Cottrell's dust-absorbing method, a method of catching fog particles 

 was tested and the electric power needed for the dissipation was calculated. 



53. Y. Takahashi : Study on the Turbulence Relating to the Artificial 



Dissipation of Fog 



In case of artificial dissipation of fog in open spaces such as air fields, 

 the dissipation eificiency decreases owing to the mixing of air current 

 from another place by turbulence. To know the extent of the decrease 

 in efficiency the vorticity in fog was measured by means of hot wire 

 anemometer and resistence thermometer, and on the basis of this measure- 

 ment the dimensions and distribution of dissipating sources were discussed. 

 Further, as the result of the experimental measurement of eddy diffusivity 

 in fog by streaming the cooled air into fog, it was found that an air current 

 -of — 5° c. was the most stable. 



54. /. S'Ugaya : Device of " Fog Dissipation Car " and its Calculation 



To dissipate fog at an airfield, the method of distribution of many 

 movable heat sources was adopted and the equipment of a motor-car 

 blowing out hot air produced by the combustion of heavy oil — that is, 

 " Fog dissipation car " — was discussed. 



-35. Y. Takahashi and J. Sugaya : Trial Manufacture of " Fog Dissipation 



Car " 



According to the condition described perviously in the item 34, a 

 " fog dissipation car " was manufactured for trial whose main structure 

 is composed of a combustion cylinder of heavy-oil, a blower blowing out 

 the mixture of hot air and open air, and its motive power equipment.. 

 The trial car has the power as follows : consumption amount of heavy 

 ■oil, 60 litres per hour, amount of air blowing, 3.7 m^ /sec. temperature 

 of hot air, 70° c. 



36. U. Nakaya and J. Yoshida : Experiment on the Dissipation of Fog 

 by Means of " Fog Dissipation Car " 



The experiment on the dissipation of fog was performed at the coast 

 of Tomakomai by means of the " fog dissipation car " discussed 

 previously. The range to be dissipated by the trial car, amounted to 

 20 m. long, 5 m. wide, and 4 m. high. Further, it was shown that 

 Takahashi's calculation of eddy diffusion described previously in the 

 item 33 nearly held true. 



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