From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The various industrial and scientific applications of the STROBORAMA stroboscope.
| Identifier | ExFiles\Box 155\3\ scan0137 | |
| Date | 1st March 1937 guessed | |
| the cause of noisy brakes. A study of brakes and brake drums vibration may possibly find Pneumatic or solid tyres are made to appear at extremely slow motion while passing over obstructions set on the periphery of a test-ing drum. The tyre is clearly seen deflecting over the obstruction and reassuming its true shape. The STROBORAMA lends itself to new study of resiliency of rubber. It is suggested for the penetration of vibrations in rubber when submitted to hammer blows at different rates of speed. The same method may be used to study internal deflections within the carcase of pneumatic tyres. In a test of Shimmy, the STROBORAMA can illuminate the whole car at once and allow simultaneous observations of all the parts from any angle. HYDRAULICS: Distribution of liquid fuel in an air stream can be observed through glass windows set on the intake manifold or at the carburetter. Study of jets and emulsions at spray nozzles of carburetters or atom-isers of Diesel engines is easily conducted with the STROBORAMA. Valuable information may be gathered from the study of nozzles on steam and water turbines; on the shape of impellers. Needless to say, valuable information can be procured from photographs taken by the aid of the STROBORAMA. Figures 2 & 3 are submitted as examples and as proof of the efficiency of the STROBORAMA. No photograph is, however, essential in connection with the actual use of the STROBORAMA. Figure 2. Stroboscopic photograph taken by the University of Lausanne, Switzerland, of a Pelton Wheel in motion, showing the clarity of definition and stability of image given by the STROBORAMA. DETAILS: Three minutes time exposure; Pelton Wheel rotating at approximately 3500 r.p.m. Photograph taken in normal daylight. ------- A PROPELLER AT REST? - NO! The Blade and Fly Wheel are revolving at 2,200 r.p.m. The peripheral speed of the Blade Tips is 160 feet per second. Yet, under the illumination of the STROBORAMA, it looks just like this. (see illustration) YOU CAN EVEN READ THE NEWSPRINT ON THE BLADE! A dozen observers can see it at the same time. It is so striking that we must warn visitors to keep their hands away from the blade, which appears to them to be standing still. Figure 3:- Stroboscopic photograph of a Propeller running at high speed taken by Messrs Tillotsons(Bolton) Ltd, Bolton, who on request will certify that this illustration is printed from a block prepared from a photograph which has not been retouched in any way. Details: Five minutes time exposure-pan-chromatic plate, photograph-ed{J. L. Edwards} in normal daylight. Further data is given on the label pasted on the Propeller Blade which reads as above. The study of flow of liquids through gates and valves may be of great value. NAVAL CONSTRUCTION:- The study of Naval hulls in the test basin may use to advantage this method for observing liquid veins; also for the study of propellers. AERODYNAMICS: It is possible to study streamlined forms and wing shapes by rendering visable the veins of air with smoke filets, fine dust or light threads made to appear arrested in their linear motion. The action and distortion of propellers can also be easily seen. Not only is the STROBORAMA a valuable adjunct of the wind tunnel but its illumination is strong enough, under certain conditions, to permit observation of air streams blown by the propeller against the fuselage and wings of a plane during a ground test. Vibrations and deformations may be seen and measured. Page 4. | ||