Computer codes field calculations

A wide variety of procedures have been developed to evaluate the performance of explosives. These include experimental methods as well as calculations based on available energy of the explosives and the reactions that take place on initiation. Both experimental and calculational procedures utilize electronic instmmentation and computer codes to provide estimates of performance in the laboratory and the field. 

Models describing the adsorption of water-miscible organic compounds on natural materials have not been correlated with field observations under typical injection-zone conditions. Few computer codes contain algorithms for calculating the distribution of species between the adsorbed and aqueous states. 

The methodology that uses the dielectric model is instead the simpler and in principle the more suitable for the study of chemical reactions involving large molecular systems. In 1998, Amovilli et al [13] developed a computer code in which the solvent reaction field, including all the basic solute-solvent interactions, has been considered for Complete Active Space Self Consistent Field (CASSCF) calculations. 

While the LBNL team calculated the temperature field using their fully coupled THM model, CEA used measured in situ temperatures for their analysis. The temperature field was imported at regular time intervals into their model grid for a TM analysis. The mid-section y = 21 m was selected for the two-dimensional TM analysis. Calculations were performed using CEA s computer code Castem2000. (Verpeaux et al (1989)). 

There are also some other ideas about possible ways to make the calculation of the gradient and of the Hessian more effective, but we limit ourselves to expose topics for which there is a working computer code. The field is in evolution but surely progresses towards computational methods with computational costs and range of applicability comparable to those used for molecules in vacuo are within reach. In our opinion the most difficult point is to find search algorithms for critical points able to treat in a more efficient way some small roughness in the PES introduced by the tessellation of the cavity surface. 

In the analytical part of the programme, different available computer codes have been developed further and adapted in order to be used for mixing layer calculation. To accurately predict the flow fields and temperature distribution in the pools a satisfactory validation of codes, based on a reliable experimental data base, must be performed. 

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