No abstract

No abstract

The concept of the cell size of multifront gaseous detonation proposed about 40 years ago is used widely to estimate other detonation parameters: the critical initiation energy and critical diameters. In this paper the review of all known models for calculation of the cell size as the main detonation parameter is presented. Models were analyzed on their physical basis and basic assumptions. All models were checked also on their correctness to estimate the cell size for different mixtures. The calculated values of cell size were compared with available experimental data. On the basis of such comparison only some models are recommended for engineering calculations in practical applications. The formulas for estimating important detonation parameters with the dimension of length are proposed. Nomenclature A = preexponential factor, sec mol=cm 3 a, b = transverse and longitudinal cell sizes, respectively c 1 , P 1 = sound velocity and pressure in the induction zone D 0 = Chapman-Jouguet detonation wave velocity (chemical equilibrium calculation) D 2 , D ? = velocities of shock wave and transverse wave at collision E = effective activation energy, kcal=mol E 0 = collision energy [f], [o], [in] = concentrations of fuel, oxidant, and inert; mol cm 3 M = Mach number (M D 0 =c 0 , M 2 D 2 =c 0 , M ? D ? =c 0 ) P 0 , c 0= initial pressure and sound speed Q = specific chemical heat release R; r = shock front radii from two neighboring microexplosions at a certain time instant (R 0 r 0 at collision moment) r = coordinate of shock front r 2 , t 2 = shock wave radius and instant of transverse wave collision r , t = shock wave radius and instant when the latest particle crosses the shock front, for the latest particle the ignition delay is over at instant of transverse wave collision T = temperature t = time u = particle velocity in the laboratory frame of reference x = r =b y = =2b = parameter of the model of a strong point explosion = parameter of the model of a detonation wave with instantaneous chemical reaction behind the shock front = adiabatic exponent of initial mixture e = equilibrium adiabatic exponent of detonation products " = E 0 =4 0 D 2 0 b 2 p = transverse wave size at collision moment ij = P i =P j 0 = initial mixture density = = 0 = ignition delay

No abstract

No abstract

No abstract

No abstract

No abstract