Jouguet Theory

The treatment of sustained deton, often called the Chapman-Jouguet theory, is based on four assumptions  

3) the deton products approach a state of chem equilibrium some distance behind the deton front, and 

4) the deton vel is calculated using equations for the conservation of mass, momentum, and energy an equation of state for the deton products and the following postulate 

Chapman Jouguet postulated that the detonation velocity D is given by  

the deton vel relative to the reaction products, D-u, is equal to the local vel of sound in the reaction products. No complete theoretical proof has been given the CJ Theory, but it does agree with experimental observations 

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A purely thermodynamic treatment of detonation ignores the important question of reaction time scales. The finite time scale of reaction leads to strong deviations in detonation velocities from values based on the Chapman-Jouguet theory.16 The kinetics of even simple molecules under high-pressure conditions is not well understood. 

Chapman-]ouguet Theory. See Detonation, Chapman-Jouguet Theory... 

See also Detonation, Chapman-Jouguet Theory and also under Detonation, Theories of... 

Davis et al, "Failure of the Chapman-Jouguet Theory for Liquid and Solid Explosives ,... 

Failure of the Chapman-Jouguet Theory for Liquid and Solid Explosives , 4thONR-SympDeton (1965), pp 84-5, Abstract and Comments to the paper published in Phys-Fluids 8, 8169(1965) 7) F. Wecken,... 

Detonation, Rayleigh (or Mikhel son) Line and Transformation in. (Called here Rayleigh-MikheTson Line) The Chapman-Jouguet theory deals with adiabatic transformations in steady, non-viscous, onedimensional flows in stream tubes or ducts of constant cross-section. Such transformations can be called Rayleigh transformations. From the equation of continuity valid for flow of constant cross-section and from the momentum equation (Ref 1, p 117 Ref 2, p 99), with use of the formula c = y-Pv for sonic velocity in an ideal gas, can be derived the relationship ... 

Schweikert s theory differs radically from the conventional thermohydrodynamic Chapman-Jouguet theory in that it provides for a continuous transition from burning to deton. In Section I entitled "Introduction , the author criticizes the validity of the C-J theory for condensed expls. In Section II the burning rate constants of a colloidal propint are related to fundamental parameters such.as specific surface vol of the powd, the most probable molecular vel, and the collision efficiency c. Schweikert arrives in Section III at the conclusion that burning deton differ primarily in the magnitude of c i.e. c l in a deton and is a much. smaller value in a burning process A surprisingly simple relation is derived in Section IV for the upper boundary of the deton vel Dm of a condensed expl ... 

R. Becker, Zeitschrift fur Physik 8, 321-62(1922) (Shock waves and detonation application of Chapman-Jouguet theory to solid expls) 9) G. Schweikert, "Innere Ballistik , Springer, Leipzig(1923), 31 ff (Theory of deton of solid liq expls)... 

Chapman-Jouguet theory see Detonation (and expln) theories 4 D601... 

As in consideration of deflagration phenomena, other parameters are of import in detonation research. These parameters—detonation limits, initiation energy, critical tube diameter, quenching diameter, and thickness of the supporting reaction zone—require a knowledge of the wave structure and hence of chemical reaction rates. Lee [6] refers to these parameters as dynamic to distinguish them from the equilibrium static detonation states, which permit the calculation of the detonation velocity by Chapman-Jouguet theory. 

The next section deals with the calculation of the detonation velocity based on Chapman-Jouguet theory. The subsequent section discusses the ZND model in detail, and the last deals with the dynamic detonation parameters. 

Detonations of the condensed homogeneous explosives nitromethane and liquid TNT were found to exhibit unstable periodic behavior. The steady-state Chapman-Jouguet theory of the detonation process will not properly describe the behavior of homogeneous explosives that exhibit such unstable behavior. 

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