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This paper describes the technique and results of an experimental study of the ignition of condensed materials (model composite propellants) by a hot single metal particle. The dependence of the ignition delay of condensed materials (CMs) on the initial particle temperature is investigated. The mechanism of interaction of a single particle heated to high temperatures with unmetallized and metallized CMs is analyzed. It is found that the presence of a metallic filler in the CM changes the absolute values of the ignition delay and the relative characteristics of their spread.

Abstract.The results of mathematical simulation of the heat transfer processes in the closed domain, which corresponds to production accomodation with the gas infrared emitter operation condition are presented. The system of differential Navier-Stokes equations in the approximation of Boussinesq is solved. The comparative analysis of thermal conditions formation in the closed domain is carried out taking into account heat withdrawal through the upper enclosing construction and under the conditions of its heat insulation. The essential transiency of the analyzed heat transfer process and the influence of heat withdrawal from one of the outer boundaries on the mean temperatures values in largedimension industrial premises are established.The distinguishing feature of modern industry becomes the rigid savings of energy consumption, as a rule, for the purpose of reduction in the economic expenditures. Localization of systems and heat supply sources is one of the ways for reduction in total energy expenditures for the heating of large production accomodations (local heating of separate workplaces). As the most acceptable version the system of gas infrared emitters (GIE) [1] can be used. Scale GIE introduction in the production is strongly limited because of the insufficient experimental and theoretical study of convective heat transfer in the largedimension accomodations with the gas infrared emitters operation conditions.For the mathematical simulation of the studied process the process description of free convection in air region and thermal conductivity in enclosing constructions (Fig. 1) is necessary. In the problem statement system conjugate heat transfer equations [2-5] was used as a base. All energy from emitter came to bottom medium interface H H .To analyze the significant factors impact on the thermal modes in the manufacturing conditions of GIE operation two versions of the heat transfer problem statement were considered. The first version: heat insulation conditions are satisfied on all outer boundaries of solution region. The second: on upper boundary of solution region y = H (Fig. 1) heat exchange condition with environment is satisfied. The problem was solved in the dimensionless formulation.The system of equations describing the heat transfer in the system has the form:1 Sh

An experimental and numerical analysis was performed to investigate the laminar regimes of conjugate thermogravitational convection in a closed parallelepiped with heat-conducting walls of finite thickness in the presence of a local energy source with convective heat exchange with the environment. The numerical studies were performed using the Fluent software. The experimental data and numerical results agree well each other.

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Abstract.Results of mathematical modeling of convective heat transfer in air area surrounded on all sides enclosing structures, in the presence of heat source at the lower boundary of the media are presented. Solved the system of differential equations of unsteady Navier-Stokes equations with the appropriate initial and boundary conditions. The process of convective heat transfer is calculated using the models of turbulence Prandtl and PrandtlReichard. Takes into account the processes of heat exchange region considered with the environment. Is carried out the analysis of the dimensionless heat transfer coefficient at interfaces "air -enclosures". The distributions average along the gas temperature range are obtained.

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