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The paper gives the description of boundary element method (BEM) with subdomains for the solution of convection—diffusion equations with variable coefficients and Burgers’ equations. At first, the whole domain is discretized into K subdomains, in which linearization of equations by representing convective velocity by the sum of constant and variable parts is carried out. Then using fundamental solutions for convection—diffusion linear equations for each subdomain the boundary integral equation (in which the part of the convective term with the constant convective velocity is not included into the pseudo‐body force) is formulated. Only part of the convective term with the variable velocity, which is, as a rule, more than one order less than convective velocity constant part contribution, is left as the pseudo‐source. On the one hand, this does not disturb the numerical BEM—algorithm stability and, on the other hand, this leads to significant improvement in the accuracy of solution. The global matrix, similar to the case of finite element method, has block band structure whereas its width depends only on the numeration order of nodes and subdomains. It is noted, that in comparison with the direct boundary element method the number of global matrix non‐zero elements is not proportional to the square of the number of nodes, but only to the total number of nodal points. This allows us to use the BEM for the solution of problems with very fine space discretization. The proposed BEM with subdomains technique has been used for the numerical solution of one‐dimensional linear steady‐state convective—diffusion problem with variable coefficients and one‐dimensional non‐linear Burgers’ equation for which exact analytical solutions are available. It made it possible to find out the BEM correctness according to both time and space. High precision of the numerical method is noted. The good point of the BEM is the high iteration convergence, which is disturbed neither by high Reynolds numbers nor by the presence of negative velocity zones.

The world community has long striven for the liquidation of chemical weapons of mass destruction. The 1925 Geneva treaty “On the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacterial Methods of Warfare” was the first international accord on chemical weapons prohibition. Signed by 125 countries, the USSR ratified the treaty in December 1927. The later development of the “Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and their Destruction” (henceforth “the Convention”) followed this early step and was undertaken with Russia's active participation. The Convention was signed by the Russian Federation in January 1993 and ratified by the State Duma in November 1997 with the decision to end chemical weapons stockpiling by 2007. As a signatory, Russia accepted international responsibilities for solving many interrelated problems, paramount among them was the protection of people and the environment (The Convention…, 1994, item 4).