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Currently, methods of three-dimensional printing of products from polymer, metal and ceramic materials are widely used. Layer-by-layer synthesis technologies make it possible to obtain high-quality products with sufficiently high mechanical characteristics close to those realized using traditional technological processes. A related problem is solved, including calculating the temperature in the product and the operation area surrounding it in a flat setting based on two different approaches. For a layer-by-layer extensible body, the unsteady heat conduction problem is stated. At each step, the height of the computational region increases due to the filling of a new layer of powder. One time step of the calculation is determined by the interval between two consecutive passes of the laser. The temperature distribution found at each step is used as the initial conditions for the calculations at the next step. The temperature field obtained as a result of solving the problem that is implemented in the product in question with a step of 1000 (after applying and melting 1000 layers) is further compared with the solution of the quasi-stationary problem for the finite dimensions product. Using the example of the simple geometry taken, it is shown that a quasi-stationary solution can provide a satisfactory estimate of the macroscopic thermal state of the growing product. [ABSTRACT FROM AUTHOR]

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On the basis of mathematic simulation, the problem of optimizing the energy storage and the massdimensional parameters of the mechatronic modules of aviation equipment is solved by synthesizing the structure and analyzing the characteristics of various power supplies, a generalized model of the power supply source developed for various power supply sources of the drive control systems is given, a theoretical review of the currently used chemical current sources is carried out, the comparison of sets of external characteristics of capacitive and pneumatic storage media with a set of external characteristics of the chemical current source. The generalized model of the aircraft power supply source, described in the article, can be used in the design of highly efficient mechatronic modules of control systems for autonomous mobile objects of a new generation. [ABSTRACT FROM AUTHOR]

An analytic solution of a Stefan-type problem with one non-stationary moving boundary of phase transformations simulating linear heat transfer in an inhomogeneous medium is considered. In simulating the heat and mass transfer process, the generalized heat equation is used, taking into account the finite rate of heat distribution Cq . This formulation of the problem adequately describes the thermal state of the materials during their high-temperature heating, where the pressure is taken into account because of the low rate of filtration of the pyrolysis gases. It is assumed that the braking pressure should exceed the ambient pressure by the hydraulic resistance of the porous residue. Comparison of numerical and analytical solutions is performed, both. [ABSTRACT FROM AUTHOR]

Copyright of Periódico Tchê Química is the property of Grupo Tche Quimica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Periódico Tchê Química is the property of Grupo Tche Quimica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)