Shock adiabatic

The Rankine-Hugoniot curve is sometimes referred to as the shock adiabat (especially in the Soviet literature). This terminology reflects the fact that the shock process is so fast that there is insufficient time for heat... 

The book includes among other topics Definition of expln and classification of expln processes, pp 9-l6 Theory of shock waves, which includes "shock adiabat on p 190 (pp 182-224) Theory of deton waves (pp 225-27) Hugoniot curve for detonation waves (p 228) Hydrodynamic Theory of deton (p 226) Explosion in air. (pp 555-663) Theory of point initiation of deton, called in Rus "Teoriya tochechnago vzryva (pp 598-624) Theory of spherical expln (pp 624-40) Explosion in condensed medium (pp 664-81) Propagation of shock waves in water (pp 681-90) Some problems of theory of deton in liquids (pp 690-98) Propagation of waves in solids (pp 708-18) and Theory of deton in earth. (pp 718-44)... 

It can be stabilized against explosion by shock (adiabatic compression by a piston) by adding 75 parts by weight of either EtOH,... 

Fig. 1.22 Shock adiabat for an explosive and the detonation products (detonation in stationary state).

Fig. 3.1 Schematic representation of the detonation process and the shock-wave structure (a) as well as the shock adiabat for an explosive and the detonation products (detonation in a stationary state) (b).

The p(V) diagram shows the shock adiabat of the explosive, which is also called the Hugoniot curve or Hugoniot adiabat (see Fig. 1.22). The shock adiabat can be calculated for both the non-reacted explosive as well as for the reaction products (see Fig. 1.22). The C-J point, which represents the point where the C-J conditions are fulfilled, is therefore the point where the shock adiabat of the reaction products touches the Raleigh line (tangent), which is described by the following equation ... 

Small Arms of the World , Stackpole, Harrisburg, Pennsylvania (1960), pp 566—601 62) B.S. Dyukhin et al, Measurement of the Shock Adiabatic Curves for Cast TNT Crystalline RDX and Nitromethane , DokladyAkad-Nauk 131 (4), 793-96 (1960) [Technical Information Library Services Translation TIL/T.5186, British Ministry of Aviation, London (1961)] 63) R.P. Antonelli, Encyclo-... 

Figure 2.14 shows that the detonation with propagation velocity D = D starts from the crosspoint N of the Hugoniot curve and shock adiabatic curve. Only after passing point P is under pressure detonation point (or weak detonation point) is reached. Von Neumann named the detonation velocity as eigenvalue detonation... 

Equation (2.28) establishes a relationship between pressure and specific volume (enthalpy is related via heat capacity and Eq. (2.29) with pressure and specific volume). It is called Hugoniot equation or Hugoniot shock adiabatic and consists of thermodynamic quantities only. 

The upper (p2 Pi) branch represents supersonic waves. As shown in Fig. 3, a kink occurs in the adiabat where it crosses the phase boundary, this results in two solutions for the downstream state for given wave velocity oo > Wx > Wmin- Using combustion terminology, this is known as the detonation branch of the adiabat. The solution passing through the kink has the minimum wave velocity (520 m/s) but unlike chemical explosives, this is not a CJ solution since the downstream flow is not sonic. States on the small portion of the adiabat accessible within the saturation region have supersonic downstream flow as discussed by Fowles [7]. No CJ point exists further up the adiabat from the kink since these states are simply a continuation of the shock adiabat in the metastable liquid. 

The shock adiabat of this fluid is a monotonic curve, but oscillations of the shock front are possible. Assume additional condition... 

Bulk moduli and pressure derivaties allow not only to definite volumes of solids at high static pressures, but also to calculate the parameters of shock adiabats (Hugoniot... 

Under the influence of the dynamic properties of the shock-wave, a thin layer of still unreacted explosive from the original specifie volume (lo = 1/po) along with the shock adiabat of the corresponding explosive (or Hugoniot adiabat) is compressed to volume Vi (Fig. 1.22). The pressure inereases from pq to pi as a consequence of the dynamic compression, which subsequently results in an increase of the temperature in the thin compressed layer of the explosive (Figs. 1.21 and 1.22), which causes initiation of the chemical reaction. At the end of the chemical... 

The gradient of the Rayleigh line is detemiined by the detonation velocity of the explosive. In agreement with the postulate of Chapman and Jouguet, this Rayleigh line is also a tangent to the shock adiabat of the detonation products at exactly the point which corresponds to the end of the chemical reaction (V2, p2). This point is therefore also referred to as the Chapman-Jouguet Point (C-J point). 

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