Detonation described

The actual filling of brass or aluminium delay elements is similar in principle to the filling of plain detonators described above. The loading is, however, carried out in a number of stages so as to ensure uniformity of density of the column throughout its length. 

Detonation, Slow, Same as "Low Order Detonation , described under Detonati6n High-, Low-, and Intermediate-Order -Velocities of ... 

By 1946, the best exptl values of the deton velocities had become somewhat different from 1943 values employed by Boggs Martin and this resulted in a somewhat different value of the covolume constant. A small residual variation in the covolume constant with density of expl suggested that the parameter of eq 23 should be re-evaluated. It was felt that the use of a T (jn lieu of T ) dependence of the covolume on temperature (which, would necessitate the re-evaluation of both the covolume constant and /S) would improve the agreement betw theory and experiment for cold expls (expls with. low temp of deton, like NGu) without sacrificing the excellent agreement obtd by Boggs Martin for the expls with higher deton temps (Ref 39, p 87). The hydrothermodynamic theory of detonation described in Ref 32 was used in calculation of expl properties of Amatex, 50/50-Amatol, 60/40-Amatol, TNT Composition B... 

Instantaneous electric detonators described in NOLR 1111 (Ref 23, pp 4-14 to 4-19) include Navy electric detonators Mk46 Mod O Mk51 Mod O and Army detonator M36. They are shown here in Figs 1-27,... 

Electric (or Electronic) Fuze is one which depends for its arming and functioning upon events of an electronic nature. Such a fuze may be provided by any of the electric detonators described here under Electric Detonators Used in US Fuzes. For example, Point Initiating Base Detonating Fuze,... 

Calculations were performed for 1.27, 5.08, 7.62, and 10.16 cm radius spheres of 9404 and detonator, with the detonator described by a 0.2 cm radius PETN hot spot, which initiated the surrounding 0.56 cm thick layer of high-density PETN. The BKW or gamma law equation of state for 9404 with an effective C-J pressure of 365 kbar and a gamma of 2.914 yielded the lower dashed curve in Figure 2.43 for a 10.16 cm radius sphere. The free-surface velocity of the 1.27 cm radius sphere was about 1% less than that of the 10.16 cm thick sphere at the same scaled thickness. 

Taylor wave (TW) Self-similar flow behind a stationary wave of detonation described by Zeldovich Ya. B and Taylor J.I. While moving off the closed end of a tube, a TW is a rarefaction wave resulting in a state of rest of the products flow in the process of their isentropic expansion. The length of a TW in the detonation process is half the distance between the closed end and the detonation front. 

The term detonation often employed to describe knocking is incorrect because the phenomenon can not be attributed to the propagation of a flame in the supersonic region, accompanied by a shock wave.. 

In 1962, the first method for welding (qv) metals ia spots along a linear path by explosive detonation was patented (8). This method is not, however, used iadustriaHy. In 1963, a theory that explained how and why cladding occurs was pubHshed (9). Research efforts resulted ia process patents which standardized iadustrial explosion cladding. Several of the patents describe the use of variables iavolved ia parallel cladding which is the most popular form of explosion cladding (10—13). Several excellent reviews on metal cladding have been pubHshed (14—16). 

Peroxide Formation. Except for the methyl alkyl ethers, most ethers tend to absorb and react with oxygen from the air to form unstable peroxides that may detonate with extreme violence when concentrated by evaporation or distillation, when combined with other compounds that give a detonable mixture, or when disturbed by heat, shock, or friction. Appreciable quantities of crystalline soHds have been observed as gross evidence for the formation of peroxides, and peroxides may form a viscous Hquid in the bottom of ether-fiHed containers. If viscous Hquids or crystalline soHds are observed in ethers, no further tests for the detection of peroxides are recommended. Several chemical and physical methods for detecting and estimating peroxide concentrations have been described. Most of the quaHtative tests for peroxides are readily performed and strongly recommended when any doubt is present (20). 

This book covers many aspects of DBA design, selection, specification, installadon, and maintenance. It explains how varions types of flame arresters differ, how they are constrncted, and how they work, ft also describes when a flame arrester is an effective solntion for mitigation of deflagrations and detonations, and other means of protection (e.g., oxidant concentration rednction) that may be nsed. It also briefly covers some aspects of dnst deflagration protection. 

Fabiano et al. (1999) describe an explosion in the loading section of an Italian acetylene production plant in which the installed flame arresters did not stop a detonation. The arresters were deflagration type and the arrester elements were vessels packed with silica gel and aluminum plates (Fabiano 1999). It was concluded that the flame arresters used were not suitable for dealing safely with the excess pressures resulting from an acetylene decomposition, and may not have been in the proper location to stop the detonation. 

An improvement on the CJ model is the ZND (Zeldovich, von Neumann, and Doring) model, which takes the reaction rate into account (Nettleton 1987, Classman 1996, Lewis and von Elbe 1987). The ZND model describes the detonation wave as a shock wave, immediately fol-... 

Sutherland and Wegert (1972) describe the successful use of the Linde hydraulic valve arrester in stopping an acetylene decomposition detonation. As previously noted, these flame arresters are no longer being made by Linde (now Praxair Inc,), but are still available from ESAB Welding Sc Cutting Products of Florence, SC. 

Nichols (1999) describes a nnmber of reaction forces that are generated dnring deflagrations and detonations in piping systems snch as ... 

For describing structural loading functions needed for design analysis, the use of overdriven detonation data representing the net overpressure (run-up side less protected side overpressure) on the arrester element and supporting structure is preferable to data representing only the run-up side, side-on overpressure. However, the run-up side transient history of side-on overpressure for overdriven detonations should provide a conservative estimate for design purposes (see Chapter 6). 

This volume consists of two parts Chapters 1-6 and Chapters 7-9. Chapters 1 through 6 offer detailed background information. They describe pertinent phenomena, give an overview of past experimental and theoretical research, and provide methods for estimating consequences. Chapter 2 describes the phenomena covered, identifies various accident scenarios leading to each of the events, and describes actual accidents. In Chapter 3, principles such as dispersion, deflagration, detonation, blast, and radiation are explained. 

This chapter describes the main features of vapor cloud explosions, flash fires, and BLEVEs. It identifies the similarities and differences among them. Effects described are supported by several case histories. Chapter 3 will present details of dispersion, deflagration, detonation, ignition, blast, and radiation. 

The one-dimensional representation described above is too simple to describe the behavior of a detonation in response to boundary conditions. Denisov et al. 

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