§ 233. Dines' Experiments.[1] Method.—Coming now to the modern period, we have to examine two independent series of experiments, made almost simultaneously, respectively by Mr. W. H. Dines in England and by the late Prof. S. P. Langley in America.
To Dines we owe a particularly beautiful and original method of employing the whirling table for the determination of aerodynamic data. In all the modern applications of the whirling table,
Fig. 141. the determination of the resistance of the object of experiment is made quite independently of the propulsion of the table, some form of balance being employed mounted at the extremity of the rotating arm, the motion of the latter being maintained by the application of a power installation, and the speed of rotation accurately recorded by a chronograph. Dines conceived the possibility of balancing the aerodynamic reaction, which varies approximately as the square of the velocity,
- ↑ In the present account of the investigations of Mr. Dines, the following publications have been consulted:—"Some Experiments made to Investigate the Connection between the Pressure and the Velocity of the Wind" (Dines, Quart. Journ. Royal Met. Soc., Vol. XV., October, 1889), and "On Wind Pressure upon an Inclined Surface" (Dines, Proc. Royal Soc., Vol. XLVIII., 1890). Further particulars of Mr. Dines' experiments of aerodynamic interest will be found in the following:—"Mutual Influence of two Pressure Plates upon each other," and "On the Variations of Pressure caused by the Wind Blowing across the Mouth of the Tube" (Dines, Quart. Journ. Royal Met. Soc., Vol. XVI., October, 1890).
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