Naslov
Izračunavanje eksplozijskih performansi korištenjem EXPLO5 računalnog koda
(Calculation of explosives performances by EXPLO5 code)

Autori
Sućeska Muhamed

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, pp prezentacija, znanstveni

Izvornik
Modelling of Reaction Products and Temperatures / Ernst Christian Koch - Pfinztal : Fraunhofer institute of chemical technology (ICT), 2007

Skup
4th Workshop on Pyrotechnic Combustion Mechanisms – Modelling of Reaction Products and Temperatures

Mjesto i datum
Pfinztal, Njemačka, 25.06.2007

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
eksplozivi; pirotehnika; sagorijevanje; detonacija; modeliranje
(explosives; pyrotechnics; combustion; detonation; modelling)

Sažetak
The first version of EXPLO5 computer program was made in 1990, and results of calculation using the program were published one year later. Originally, the program was developed for the calculation of detonation parameters of high explosives. Since that time, EXPLO5 is constantly improving. At the moment, EXPLO5 has a graphical user interface for MS-Windows platform. Designed to be easy to operate, the program has the possibility to calculate detonation parameters as well as parameters of state along expansion isentrope. It has non-linear curve fitting program built in to fit relative volume-pressure data along expansion isentrope according to Jones-Wilkins-Lee (JWL) model, enabling the calculation of detonation energy available for performing mechanical work. The calculation of detonation parameters in EXPLO5 is based on the chemical equilibrium, steady-state model of detonation. The calculation of equilibrium composition of detonation products is done in the program by applying modified White, Johnson, and Dantzig’ s free energy minimisation technique. The equation system describing mathematically state of equilibrium is solved by applying modified Newton-Raphson method. The program uses Becker-Kistiakowsky-Wilson (BKW) equation of state for gaseous detonation products and Cowan-Fickett’ s equation of state for solid carbon. The program is designed so that it enables the calculation of chemical equilibrium composition and thermodynamic parameters of state along shock adiabate of detonation products, CJ state and detonation parameters at the CJ state, as well as parameters of state along the expansion isentrope. So far the program was tested on a series of high explosives having different composition and densities. It was found out that some input parameters in BKW EOS (e.g. values of covolumes of individual detonation products, set of constants, etc.) may significantly influence calculation results. Based on own parameterisation of these parameters, an own set of constants in BKW EOS is found out and used in the program (so-called BKWN set of constants ;  = 0.5,  = 0.176,  = 14.71, and  = 6620). Using this set of constants detonation velocity, pressure, temperature, heat, and energy of detonation may be predicted with the error less than 10 % for the majority of explosives. New significant modification of EXPLO5 is still in progress at the moment. The modification consists of adding the possibility of calculation of combustion performances of explosives, i.e. calculation of equilibrium composition and thermodynamic parameters of combustion products under constant pressure, or constant volume conditions. The pressure and thermodynamic parameters of combustion products are calculated by applying the ideal gas, or virial equation of state. The program may calculate the virial coefficients of individual gaseous species in different manners ; applying analytical equations derived from experimental measurements, and from intermolecular potential equations. Up to know the program was tested on homogeneous propellants (having CHNO composition), and a satisfactory agreement was found with experimental results, as well as with results of calculation by some other computer codes.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Kemijsko inženjerstvo

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