Pressure shock wave

McQueen, R.G. and J.N. Fritz (1982), Some Techniques and Results from High-Pressure Shock-Wave Experiments Utilizing the Radiation from Shocked Transparent Materials, in Shock Waves in Condensed Matter—1981 (edited by W.J. Nellis, L. Seaman, and R.A. Graham), American Institute of Physics, New York, 193-207. 

In 1963, McQueen, Fritz, and Marsh (J. Geophys. Res. 68, p. 2319) suggested that the high-pressure shock-wave data for fused quartz (Table 1) and the data for crystal quartz pg = 2.65 g/cm, Co = 1.74 km/s and s = 1.70, both described the shock-induced high-pressure phase of SiOj, stishovite pg = 4.35 g/cm ), above 50 GPa. Assume Ej-j, = 1.5 kJ/g show that these shock data are consistent with a constant value of y = 0.9 in the 50-100 GPa range. 

In extreme cases, very high pressure waves are encountered in which the time to achieve peak pressure may be less than one nanosecond. Study of solids under the influence of these high pressure shock waves can be the source of information on high pressure equations of states of solids within the framework of specific assumptions, and of mechanical, physical, and chemical properties under unusually high pressure. 

The low vel is in the vicinity of the vel of sound and thus corresponds to a relatively low pressure shock wave. The capability of slow detonation depends especially upon the physical state of the expl for gelatinized... 

In order to avoid having to shut down the whole vacuum system each time the cryostat is vented after an experiment, it is advisable to place a small slide or butterfly valve between the turbopump and the expander port. When the system is reevacuated, the turbopump must be stopped before opening the valve, otherwise the ambient pressure shock wave that results might deform the delicate rotor and... 

The only differences are that it endures for a shorter period of time and the vertical lines of the square wave are changed to the sloping lines of a sine wave. If the time of valve closure were exactly 2Lie, the maximum pressure rise at the valve would still be the same but the curves of the sine wave would all end in sharp points for both maximum and minimum values, as the time of duration would be reduced to zero. These references to square and sinusoidal pressure shock waves are based on an experimental pipe with the following data L = 3060 ft, internal diameter = 2.06 in, c = 4371 ft/s, V = 1.11 ft/s, Vc/g = 151 ft, 2Lie = 1.40 s, static head = 306.7 ft, head before waive closure = 301.6 ft, hf= 5.1 ft. For the square wave, the time of closure is 1 s, and it will be noted that the actual pressure rise is more than 151 ft. For the sine wave, the time of closure is 3 s. 

Destructive effects of underwater detonations, differ in their distant and proximity effects. The first effect is caused by the action of the pressure shock wave, the latter mainly by the thrust produced by the expanding gas bubble. 

Example 19.1 A constant-pressure shock wave is traveling to the right in a thick slab of polysytrene. The shock pressure is 6.5 GPa. 

Example 19.2 Let us suppose that a polyethylene flyer, 5 mm thick, traveling at 2.5 km/s impacts a thick slab of PBX9404-03 explosive. What pressure shock wave will be driven into the explosive, and what is its initial time duration ... 

The screech noise would not exist if the flare operated below the critical gas pressure. Below the critical gas pressure shock waves do not form, which causes screech noise. The summation of the combustion roar, gas jet mixing noise, and screech noise provides the total SPL prediction emitted from the flare. 

Detonation is an instantaneous decomposition of the explosive material in which all of the sohd material changes to a gas instantaneously with the release of high heat and pressure shock waves. Detonation is the only type of chemical explosion that wiU produce a true shock wave. A material that detonates is considered a high-yield explosive (see Figure 3.11). Blast pressures can be as much as 700 tons/sq in. 

By high pressure shock wave experiments it was possible to obtain the full transition to the high pressure range and to study the high pressure limiting rate in the range 1400 2000 K. A high pressure... 

With high pressure shock waves the high pressure regions for CO2, CSg and COS dissociation could also be observed. As shown in Table 1.7 the low pre-exponential factors of the rate constants again indicate that the reactions are spin-forbidden. An analysis of these values, similar to ref. 66f, leads to the conclusion that the electronic... 

The conclusions from the several hundred measurements suggest that the reaction time of positive pressure shock waves from condensed explosives is generally 2-10 ms from the liquid explosives is 15 9 ms, for certain special liquid explosives, the action time reaches 80 ms. In certain degree, the detonation velocity/ rate is lower than condensed explosives, but the impact capacity of liquid explosives are higher than condensed ones. 

De Bruyker D, Puers R (2001) Experimental characterization of the reference channel of a differential pressure sensor using pressure shock waves. J Micromech Microeng 11 390-396... 

Explosives are materials that combust at an extremely fast rate to form a pressure-shock wave. Explosives can be classified into two groups low explosives, with pressure waves traveling at less than 3,300 feet per second (fps), and high explosives, with transonic shock waves (>3,300 fps). 

Rockwell RL (1969) Nonlinear analysis of pressure shock waves in blood vessels. Ph.D. Dissertation, Stanford University... 

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