Rotating-drum camera

Messerly, "A Rotating Drum Camera for the Optical Studies of Detonations , OSRD 682... 

Fig 86 of Ref 8, p 290 (shown here as Fig 6) gives relation between log D and log p for TNT (Trotil. in Rus) and RDX (Gheksoghen in Rus), phlegmatized with 5% paraffin. The work was done by Shekhter. D was detd by rotating drum camera. and compared with values calcd from the formula ... 

PETN and RDX in a special vacuum impact machine. Their.results showed that gases developed on impact approximate mote closely those developed on thermal decomposition chan those on deton. The results are in harmony with the hypothesis of a thermal origin of impact-initiated explns and with the slow initial burning velocities observed with the rotating drum camera... 

Acetylene-Air Mixtures. Various CaHa—air mixtures were detonated in rubber balloons by means of central elec detonators. Photographs of spherical explosions thus produced were made with a rotating-drum camera and with a 6000-frame-per-sec movie camera. 

J)Rotating Drum Camera. See under Drum Camera... 

The experiments of Kistiakowsky and Kydd [1] were done by single-pulse photolysis with a 500-J flashlamp, the reaction vessel contents being sampled via a pinhole leak into the electron ionization source of a Bendix time-of-flight (TOF) mass spectrometer. Mass spectra were obtained by pulsed extraction of ions from the ion source at 50-fis intervals after the flash. The signal from the electron multiplier detector was displayed on a cathode ray tube, which was photographed with a rotating drum camera. 

Rotating Drum Camera. See under Cameras, High-Speed Photographic in Vol 2, C14-L, and Chronographs and Other Devices Used for Measuring Detonation Velocities of Explosives in Vol 3, C311-L... 

The amplified signals from the crystals—the four gages were connected in parallel —were impressed on the horizontal-deflection plates of the cathode-ray tube. The screen of the tube was photographed with a rotating-drum camera. The drum ran at a uniform speed and, therefore, the time base was linear. Time calibration was obtained by means of a flashing neon crater tube (Sylvania, Type R1130B) which was activated by a 1000-cycle tuning-fork oscillator. The crater tube was in the... 

The rotating-drum camera is an older type of camera that is suitable for the estimation of the combustion processes of propellants and explosives. A schematic illustration of the operating principle of the rotating-drum camera and the way the distance-time curve is formed is similar to other types of cameras and is given in Figure 4.4. 

The main parts of the rotating-drum camera are a hollow drum, an electric motor, an electronic synchronising system, and a time pulse generator. 

The principle of the formation of the distance-time curve vdien using a rotating-drum camera is as follows. 

The rotating-mirror streak cameras have a writing speed of a few mm/ps, which is some ten times greater if compared to the rotating-drum cameras. 

The drop impact was recorded simultaneously in both vertical and lateral perspectives with two cameras first, a high-speed rotating drum camera, which recorded the two perspectives of the drop impact on a 35 mm b/w film. This camera records the first 66 ms of the drop impact with a frame rate of 1666 Hz. The lateral perspective pictures give information about the impact angle a = 12 zb 1° and the impact velocity m = 2.3 zb 0.1 m/s, from which the Weber number We = pDu /cr = 380 zb 20 was deduced, where p is the drop liquid density, D the drop diameter, u the drop impact velocity, and a is the surface tension. 

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