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The problem of finding optimal parameters of a heat-supply system (HSS) is in ensuring the required throughput capacity of a heat network by determining pipeline diameters and characteristics and location of pumping stations. Effective methods for solving this problem, i.e., the method of stepwise optimization based on the concept of dynamic programming and the method of multicircuit optimization, were proposed in the context of the hydraulic circuit theory developed at Melentiev Energy Systems Institute (Siberian Branch, Russian Academy of Sciences). These methods enable us to determine optimal parameters of various types of piping systems due to flexible adaptability of the calculation procedure to intricate nonlinear mathematical models describing features of used equipment items and methods of their construction and operation. The new and most significant results achieved in developing methodological support and software for finding optimal parameters of complex heat supply systems are presented: a new procedure for solving the problem based on multilevel decomposition of a heat network model that makes it possible to proceed from the initial problem to a set of interrelated, less cumbersome subproblems with reduced dimensionality; a new algorithm implementing the method of multicircuit optimization and focused on the calculation of a hierarchical model of a heat supply system; the SOSNA software system for determining optimum parameters of intricate heat-supply systems and implementing the developed methodological foundation. The proposed procedure and algorithm enable us to solve engineering problems of finding the optimal parameters of multicircuit heat supply systems having large (real) dimensionality, and are applied in solving urgent problems related to the optimal development and reconstruction of these systems. The developed methodological foundation and software can be used for designing heat supply systems in the Central and the Admiralty regions in St. Petersburg, the city of Bratsk, and the Magistral’nyi settlement. 相似文献
83.
A. N. Sokolov A. A. Shul’zhenko V. G. Gargin M. G. Loshak L. I. Aleksandrova A. S. Nikolenko V. V. Strel’chuk A. N. Katrusha O. M. Kutsai 《Journal of Superhard Materials》2012,34(3):166-172
The structure evolution of octahedral natural diamond single crystals has been studied depending on the HPHT treatment using Raman scattering and infrared spectroscopy. It has been found that the formation of a polycrystalline diamond capsule around a single crystal at p = 8 GPa and T = 1500°C gives rise to a combined structural-stressed state in the single crystal due to its plastic strain. This state has been manifested by a significantly (more than double) broadening of the characteristic line of diamond (1332 cm?1) in the Raman spectrum and the increase of a single crystal hardness from 105 to 120 GPa. 相似文献
84.
V. B. Bozhevol’nov A. M. Yafyasov V. Yu. Miailovskii Yu. V. Egorova A. A. Sokolov E. O. Filatova 《Semiconductors》2014,48(6):792-795
The charge properties of a multilayer structure, composed of silicon-carbide polytypes on a silicon substrate, are investigated. Knowledge of the properties of the space-charge region of silicon and the possibility of affecting the surface of a structure by the field effect [1] provides data on the charge processes at the interfaces between the polytypes. These data are urgent for improving the methods of synthesizing electronic structures based on SiC polytypes. 相似文献
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Zorin I. V. Dubtsov Yu. N. Sokolov G. N. Lysak V. I. 《Metal Science and Heat Treatment》2019,60(11-12):757-763
Metal Science and Heat Treatment - Special features of structure and phase formation in deposited metal based on alloyed Ni3 Al nickel aluminide formed due to high-gradient crystallization under... 相似文献
89.
S. A. Sokolov 《Russian Engineering Research》2018,38(3):151-156
A local approach is developed for calculating the fatigue strength of welded metal structures, selecting the basic weld structure, and identifying the group of welded structures corresponding to that basic structure. To that end, the stress state of typical welded structures is analyzed on the basis of two-level stress concentrators. The results may be used to develop standards for calculating the fatigue strength of welded metal structures. 相似文献