著者
山名 正夫
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空学会誌 (ISSN:00214663)
巻号頁・発行日
vol.14, no.149, pp.170-176, 1966-06-05 (Released:2009-07-09)
参考文献数
8

The phenomenon of "Hitodama", a fairly popular term from ancient in Japan and probably corresponding to will-o'-the-wisp, is studied from the viewpoint of combustion of gases. The viewpoint has come out of the examination on nearly 100 actual examples mostly observed by the acquaintances of the author. An experimental simulation is tried in a wind-tunnel, in which the setup is so devised that the mixing of methane and surrounding air is caused merely by interdiffusion. A long, horizontal column of methaneair mixture thus formed is ignited to establish a propagating flame. The observed flames take three representative types; long one with a ringshaped head, one with a conically-grooved head, and spherical one with a short tail, according to the concentration profile in the column. The analytical investigation gives calculated shapes of methane flames which are in a fairly good agreement with observed ones.
著者
山名 正夫
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空学会誌 (ISSN:00214663)
巻号頁・発行日
vol.2, no.6, pp.108-112, 1954-03-31 (Released:2009-07-09)
参考文献数
3

Some of the wartime Japanese navy planes at their experimental stages were easily brought into accidental (or unintentional) autorotation in acrobatic flight such as vertical turn or loop. The analytical studies, refining procedures taken against these defects and design precautions are described here.When the wing is liable to stall at its tip or at the approximate middle portion between tip and root, and when the directional stability is not sufficient under large incidence angles, the accidental autorotation will happen due to small side slip angle ψ or angular velocity r around Z axis caused by a slight and unavoidable incoordination of control. The procedures are indicated in Fig. 5.Consequently it is summarized: that the stall of main wing should grow gradually outward from root and forward from trailing edge as indicated in the right half of Fig. 6 (a), that the value of ∂Cn/∂ψ should not decrease even under large incidence angles.
著者
橋本 直輔
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空学会誌 (ISSN:00214663)
巻号頁・発行日
vol.9, no.93, pp.309-312, 1961-10-05 (Released:2009-05-25)
参考文献数
3

As a result of some simple experiments on the characteristics of jet-reaction rotor blades, the author found the existence of the pitch angle which makes hovering thrust of rotor maximum regardless of the thrust of tip jet. By some analyses, he then confirmed its existence, and investigated how the lift slope and drag coefficient of wing section affect the value of optimum pitch angle. Comparing the results of analysis with those of experiment, there found some discrepancies, on which the ambiguous characteristics of the blade-root portion seem to have a great influence, and further investigations, especially the Practical method to estimate the effects of this blade-root portion on rotor thrust and torque must be studied.