Oscillographic Techniques

Detonation Transients and Unstable Detonation Processes. Allen et al (Ref 1) made detonation velocity vs chge length. measurements on RDX (—65+100 mesh), fine grained TNT (—35 —150) coarse, low-density TNT (—8+10) 50/50 fine-coarse TNT, cast TNT, low-density. mixts of 80/20 TNT/AN, and mixts of 90/10 AN/RDX. Deton velocities were measured by a rotating mirror streak camera and by the pin oscillograph technique, in most cases simultaneously Their exptl data showed six different types of velocity transients ... 

The determination of detonation velocity is based upon measurement of the time interval needed for the detonation wave to travel a known distance through the explosive under test. The methods used to determine VOD may be classified as mechanical methods (Dautriche method), electrical methods [pin oscillographic technique (POT)], optical methods and radiographic methods. The methods which are generally used for the determination of VOD are ... 

The method, as so far developed, is limited by the condition that the hydration-dehydration reaction must proceed at a rate that is slow compared with the time needed to obtain a polarogram. In principle, the method is capable of much wider application to covalent-hydration studies if use is made of oscillographic polarographic techniques or of chronopotentiometry. These refinements are currently being investigated. 

R. Kalvoda, Techniques of Oscillographic Polarography, Elsevier, Amsterdam, 2nd ed., 1965. 

In addition to the mechanical method described there are also electromechanical measuring techniques in which the impact pressure is recorded by an oscillograph with the aid of a piezoquartz crystal. 

The determination of the thrust of a rocket motor involves recording the time diagram of the force (tons, kp, or newtons) during combustion. The force is allowed to act on a support, with a pick-up element thrust cell interposed between them. The measurement is carried out by the aid of a strain gauge element (variation of resistance with pressure) or of a piezo-quartz element, and the results are recorded on an oscillograph connected in a compensation circuit. Modern measuring and computation techniques yield the total thrust time (impulse) immediately. 

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