Search Results for “Litvin M. G.” – Collected book of scientific-technical articles https://journal.yuzhnoye.com Space technology. Missile armaments Tue, 02 Apr 2024 12:53:47 +0000 en-GB hourly 1 https://wordpress.org/?v=6.2.2 https://journal.yuzhnoye.com/wp-content/uploads/2020/11/logo_1.svg Search Results for “Litvin M. G.” – Collected book of scientific-technical articles https://journal.yuzhnoye.com 32 32 15.1.2020 Simulation of thermomechanical processes in functionally-gradient materials of inhomogeneous structure in the manufacturing and operation of rocket structural elements https://journal.yuzhnoye.com/content_2020_1-en/annot_15_1_2020-en/ Wed, 13 Sep 2023 11:07:28 +0000 https://journal.yuzhnoye.com/?page_id=31050
In this paper, based on the method of singular integral equations, we present a unified approach to the solution of thermal elasticity problems for bodies weakened by inhomogeneities. In this paper, based on the method of singular integral equations, we present a unified approach to the solution of thermal elasticity problems for bodies weakened by inhomogeneities. When the weld is cooled, it develops “hot cracks” that lead to a lack of welding elements of the structures. Litvinchuk G. Kraievye zadachi i singuliarnye integralnye uravneniia so sdvigom. Modelirovanie sistem : monografiia. Prichiny poiavliniia defektov pri shlifovanii magnitotverdykh splavov. Smeshannye zadachi mechaniki deformiruemogo tela: Tez.
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15. Simulation of thermomechanical processes in functionally-gradient materials of inhomogeneous structure in the manufacturing and operation of rocket structural elements

Organization:

Institute of Mechanical Engineering of Odessa National Polytechnic University, Odessa, Ukraine

Page: Kosm. teh. Raket. vooruž. 2020, (1); 137-148

DOI: https://doi.org/10.33136/stma2020.01.137

Language: Ukrainian

Annotation: The strength of real solids depends essentially on the defect of the structure. In real materials, there is always a large number of various micro defects, the development of which under the influence of loading leads to the appearance of cracks and their growth in the form of local or complete destruction. In this paper, based on the method of singular integral equations, we present a unified approach to the solution of thermal elasticity problems for bodies weakened by inhomogeneities. The purpose of the work is to take into account the heterogeneities in the materials of the elements of the rocket structures on their functionally-gradient properties, including strength. The choice of the method of investigation of strength and destruction of structural elements depends on the size of the object under study. Micro-research is related to the heterogeneities that are formed in the surface layer at the stage of preparation, the technology of manufacturing structural elements. Defectiveness allows you to adequately consider the mechanism of destruction of objects as a process of development of cracks. In studying the limit state of real elements, weakened by defects and constructing on this basis the theory of their strength and destruction in addition to the deterministic one must consider the probabilistic – statistical approach. In the case of thermal action on structural elements in which there are uniformly scattered, non-interacting randomly distributed defects of the type of cracks, the laws of joint distribution of the length and angle of orientation of which are known, the limiting value of the heat flux for the balanced state of the crack having the length of the “weakest link” is determined. The influence of heterogeneities of technological origin (from the workpiece to the finished product) that occur in the surface layer in the technology of manufacturing structural elements on its destruction is taken into account by the developed model. The strength of real solids depends essentially on the defect of the structure. In real materials, there are always many various micro defects, the development of which under the influence of loading leads to the appearance of cracks and their growth in the form of local or complete destruction. In this paper, based on the method of singular integral equations, we present a unified approach to the solution of thermal elasticity problems for bodies weakened by inhomogeneities. The purpose of the work is to take into account the heterogeneities in the materials of the elements of the rocket structures on their functionally gradient properties, including strength. The choice of the method of investigation of strength and destruction of structural elements depends on the size of the object under study. Micro-research is related to the heterogeneities that are formed in the surface layer at the stage of preparation, the technology of manufacturing structural elements. Defectiveness allows you to adequately consider the mechanism of destruction of objects as a process of development of cracks. In studying the limit state of real elements, weakened by defects and constructing on this basis the theory of their strength and destruction besides the deterministic one must consider the probabilistic – statistical approach. With thermal action on structural elements in which there are uniformly scattered, non-interacting randomly distributed defects of the cracks, the laws of joint distribution of the length and angle of orientation of which are known, the limiting value of the heat flux for the balanced state of the crack having the length of the “weakest link” is determined. The influence of heterogeneities of technological origin (from the workpiece to the finished product) that occur in the surface layer in the technology of manufacturing structural elements on its destruction is taken into account by the developed model. The solution of the singular integral equation with the Cauchy kernel allows one to determine the intensity of stresses around the vertexes of defects of the cracks, and by comparing it with the criterion of fracture toughness for the material of a structural element, one can determine its state. If this criterion is violated, the weak link defect develops into a trunk crack. Also, a criterion correlation of the condition of the equilibrium defect condition with a length of 2l was got, depending on the magnitude of the contact temperature. When the weld is cooled, it develops “hot cracks” that lead to a lack of welding elements of the structures. The results of the simulation using singular integral equations open the possibility to evaluate the influence of thirdparty fillers on the loss of functional properties of inhomogeneous systems. The exact determination of the order and nature of the singularity near the vertices of the acute-angled imperfection in the inhomogeneous medium, presented in the analytical form, is necessary to plan and record the corresponding criterion relations to determine the functional properties of inhomogeneous systems.

Key words: mathematical model, linear systems, singular integral equations, impulse response, defects, criteria for the destruction of stochastically defective bodies, Riemann problem, thermoelastic state

Bibliography:
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19. Rais Dzh. Matematicheskie metody v mekhanike razrusheniia. Razrushenie. V 2 t. М.: Mir, 1975.Т.2. S. 204−335.
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22. Usov A. V. Smeshannaia zadacha termouprugosti dlia kusochno-odnorodnykh tel s vkliucheniiami i treshchinami. IV Vsesoiuzn. konf. Smeshannye zadachi mechaniki deformiruemogo tela: Tez. dokl.-Odessa,1990. s.116.
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24. Vitvitskii P. M., Popina S. Yu. Prochnost i kriterii khrupkogo razrusheniia stokhaticheski defektnykh tel. K.: Nauk. dumka, 1980. 187 s.
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15.1.2020  Simulation of thermomechanical processes in functionally-gradient materials of inhomogeneous structure in the manufacturing and operation of rocket structural elements
15.1.2020  Simulation of thermomechanical processes in functionally-gradient materials of inhomogeneous structure in the manufacturing and operation of rocket structural elements
15.1.2020  Simulation of thermomechanical processes in functionally-gradient materials of inhomogeneous structure in the manufacturing and operation of rocket structural elements

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2.1.2018 Dehydration of Hydrocarbon Fuels by Method of Over-Saturation Drop https://journal.yuzhnoye.com/content_2018_1-en/annot_2_1_2018-en/ Mon, 04 Sep 2023 12:45:06 +0000 https://journal.yuzhnoye.com/?page_id=30403
Organization: Yangel Yuzhnoye State Design Office, Dnipro, Ukraine Page: Kosm. Space Rocketry Ground Infrastructure Technological Facilities: Engineering Manual. A., Litvinov A. Big Chemical Guide. Content 2018 (1) Downloads: 17 Abstract views: 358 Dynamics of article downloads Dynamics of abstract views Downloads geography Country City Downloads USA Boardman; Baltimore; Plano; Dublin; Monroe; Ashburn; Ashburn; Portland; Boardman; Ashburn 10 Singapore Singapore; Singapore; Singapore; Singapore; Singapore; Singapore 6 Ukraine Dnipro 1 Downloads, views for all articles Articles, downloads, views by all authors Articles for all companies Geography of downloads articles Salo М.
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2. Dehydration of Hydrocarbon Fuels by Method of Over-Saturation Drop

Organization:

Yangel Yuzhnoye State Design Office, Dnipro, Ukraine

Page: Kosm. teh. Raket. vooruž. 2018 (1); 6-12

DOI: https://doi.org/10.33136/stma2018.01.006

Language: Russian

Annotation: An alternative method of kerosene dehydration is proposed, which is based on application of cyclic technology of supersaturation decrease using dry nitrogen. A comparison of nitrogen and time specific consumption in dehydration operations is done and recommendations are given for their use in the cosmodromes’ launch complexes fuel storage and preparation facilities.

Key words:

Bibliography:

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2. Energy-Intensive Fuels for Aircraft and Rocket Engines / Under the editorship of L. S. Yanovsky. М., 2009. 400 p.
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8. Space Rocketry Ground Infrastructure Technological Facilities: Engineering Manual. Book 1. М., 2005. 416 p.
9. Investigation of Prospective Propellant Preparation Technologies: Scientific-Technical Report 21.18258.173ОТ / Yuzhnoye SDO. 2016. 115 p.
10. Shleifer A. A., Litvinov A. N. Prospective Technologies to Prepare Propellants with Improved Performance Properties. Ul’yanovsk, 1989. 215 p.
11. Englin B. A. Use of Liquid Propellants at Low Temperatures. 3-rd edition revised and enlarged. М., 1980. 207 p.
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13. Calculated Evaluation and Experimental Check of RPC Degassing and Saturation by Helium for Filling Cyclone-4 LV: Technical Note Cyclone-4. 22.6849.123 СТ / Yuzhnoye SDO. 2005. 29 p.

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2.1.2018 Dehydration of Hydrocarbon Fuels by Method of Over-Saturation Drop
2.1.2018 Dehydration of Hydrocarbon Fuels by Method of Over-Saturation Drop
2.1.2018 Dehydration of Hydrocarbon Fuels by Method of Over-Saturation Drop
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21.2.2017 Mass Parameter Optimization of Thermal Protective Structure for Reusable Spacecraft https://journal.yuzhnoye.com/content_2017_2/annot_21_2_2017-en/ Wed, 09 Aug 2023 12:32:56 +0000 https://journal.yuzhnoye.com/?page_id=29940
2 Organization: Yangel Yuzhnoye State Design Office, Dnipro, Ukraine 1 ; Oles Honchar Dnipro National University, Dnipro, Ukraine 2 Page: Kosm. Improving Metallic Thermal-Protection-System Hypervelocity Impact Resistance Through Numerical Simulation. Problems of Designing and Manufacturing Flying Vehicle Structures. Evaluation of Thermal Resistance of Three-Layer Honeycomb Panel Produced from YuIPM-1200 Alloy by Method of Diffusion Welding in Vacuum / I. Automatic Welding. Litvinenko / Application No. More Citation Formats Harvard Chicago IEEE AIP ДСТУ 8302:2015 ДСТУ ГОСТ 7.1:2006 (ВАК) ISO 690:2010 BibTeX на сайт ДП «КБ «Південне»
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21. Mass Parameter Optimization of Thermal Protective Structure for Reusable Spacecraft

Organization:

Yangel Yuzhnoye State Design Office, Dnipro, Ukraine1; Oles Honchar Dnipro National University, Dnipro, Ukraine2

Page: Kosm. teh. Raket. vooruž. 2017 (2); 121-126

Language: Russian

Annotation: The paper considers the TZS-U design developed by Yuzhnoye SDO specialists for windward part of reusable spacecraft with external metal three-layer panel, U-like joint and tiled thermal protection, in which the problem is solved of compensation of thermal expansions and sealing of gaps; for optimization of structural mass. The specially created dispersion-hardened powder alloy based on nichrome and aluminum with yttrium dioxide with decreased specific mass of 7500 kg/m3 and lighter felt of MKRF brand are used , and honeycomb filler of three-layer panel is replaced by the filler with square cell.

Key words:

Bibliography:
1. Aerothermal performance and structural integrity of a René-41 thermal protection system at Mach 6.6 / W. D. Deveikis, R. Miserentino, I. Weinstein, J. L. Schideler. NASA-TN-D-7943, NASA, Washington DC. 1975. 105 р.
2. Poteet C. C., Blosser M. L. Improving Metallic Thermal-Protection-System Hypervelocity Impact Resistance Through Numerical Simulation. Journal of Spacecraft and Rockets. 2004. Vol. 41, No. 2. Р. 221-232.
3. Advanced metallic thermal protection system development / M. L. Blosser, R. R. Chen, I. H. Schmidt et al. AIAA-2002-0504; AIAA, Washington DC. 2002. 56 р.
4. David E. European Directions for Hypersonic Thermal Protection Systems and Hot Structures. 31st Annual Conference on Composite Materials and Structures (Daytona Beach, FL, January 22, 2007). 44 р.
5. Gusarova I. A. Selection of Scheme of Heat Protection Tile Attachment to Reusable Spacecraft Body. Problems of Designing and Manufacturing Flying Vehicle Structures. 2016. No. 4 (88). P. 105-113.
6. Gusarova I. A. Evaluation of Thermal Resistance of Three-Layer Honeycomb Panel Produced from YuIPM-1200 Alloy by Method of Diffusion Welding in Vacuum / I. A. Gusarova, М. Parko, А. М. Potapov, Y. V. Fal’chenko, L. V. Petrushinets, Т. V. Melnichenko, V. E. Fedorchuk. Automatic Welding. 2016. No. 12 (759). P. 31-35.
7. Patent 108096 Ukraine. Method of Producing Heat-Resistant Alloy Based on Nichrome / V. V. Skorokhod, V. P. Solntsev, G. O. Frolov, Т. O. Solntseva, О. М. Potapov, V. G. Tikhiy, I. A. Gusarova, Y. M. Litvinenko / Application No. а2012 11691; Claimed 04.10.2012; Published 25.03.2015, Bulletin No. 6. 4 p.
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21.2.2017 Mass Parameter Optimization of Thermal Protective Structure for Reusable Spacecraft
21.2.2017 Mass Parameter Optimization of Thermal Protective Structure for Reusable Spacecraft
21.2.2017 Mass Parameter Optimization of Thermal Protective Structure for Reusable Spacecraft
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12.2.2017 Determination Procedure for Pneudraulic System and Its Components No-Failure Operation Probability https://journal.yuzhnoye.com/content_2017_2/annot_12_2_2017-en/ Wed, 09 Aug 2023 11:32:23 +0000 https://journal.yuzhnoye.com/?page_id=29785
Organization: Yangel Yuzhnoye State Design Office, Dnipro, Ukraine Page: Kosm. 2017 (2); 60-64 Language: Russian Annotation: The calculation procedure is proposed, the analysis is made and the ranges of optimal probability values of no-failure operation of pneumohydraulic propellant supply system and its elements are determined based on general requirements to integrated launch vehicle. Statistic Reliability Theory and Dependability Tests / Translation from English. Organization of Investigation, Methods, Mathematical Apparatus / Translation from English; Under the editorship of Buslenko N. sciential.ru/technology/kosmos/199.html . Litvin, V.
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12. Determination Procedure for Pneudraulic System and Its Components No-Failure Operation Probability

Organization:

Yangel Yuzhnoye State Design Office, Dnipro, Ukraine

Page: Kosm. teh. Raket. vooruž. 2017 (2); 60-64

Language: Russian

Annotation: The calculation procedure is proposed, the analysis is made and the ranges of optimal probability values of no-failure operation of pneumohydraulic propellant supply system and its elements are determined based on general requirements to integrated launch vehicle.

Key words:

Bibliography:
1. Berlow R., Proshan F. Statistic Reliability Theory and Dependability Tests / Translation from English. М., 1984. 328 p.
2. Lloyd D., Lipov M. Reliability. Organization of Investigation, Methods, Mathematical Apparatus / Translation from English; Under the editorship of Buslenko N. P. М.,1964. 686 p.
3. Ensuring Reliability of Prospective Injection Means. URL: http://www. sciential.ru/technology/kosmos/199.html.
4. Yuzhnoye SDO Rockets and Spacecraft / Under general editorship of S. N. Konyukhov. Dnepropetrovsk, 2000. 236 p.
5. Degtyarev A. V. et al. System Approach to Development of Modular Launch Vehicle Family / A. V. Degtyarev, А. E. Kahanov, N. G. Litvin, V. A. Shulga. DNU News (Series RKT; Issue 15). Vol. 1. 2012.
6. Reliability Analysis of Taurus-II LV Stage One Core Structure Pneumohydraulic Propellants Supply System: Technical Report / Taurus-II. 21.18231.123 ОТ. Yuzhnoye SDO, 2016. 35 p.
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12.2.2017 Determination Procedure for Pneudraulic System and Its Components No-Failure Operation Probability
12.2.2017 Determination Procedure for Pneudraulic System and Its Components No-Failure Operation Probability
12.2.2017 Determination Procedure for Pneudraulic System and Its Components No-Failure Operation Probability
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3.2.2016 Selection of Optimal Trajectories of Spacecraft Launch Vehicles https://journal.yuzhnoye.com/content_2016_2-en/annot_3_2_2016-en/ Tue, 06 Jun 2023 11:48:34 +0000 https://journal.yuzhnoye.com/?page_id=28306
1 , Litvin M. 1 Organization: Yangel Yuzhnoye State Design Office, Dnipro, Ukraine 1 ; Oles Honchar Dnipro National University, Dnipro, Ukraine 2 Page: Kosm. 2016 (2); 17-29 Language: Russian Annotation: An analysis of the existing methods of trajectories selection of spacecraft launch vehicles is performed. A generalized method is proposed for selection of optimal flight trajectories of launch vehicles in the central gravitational field when launching the artificial earth satellites. Y., Litvin M. Y., Litvin M. Y., Litvin M. Y., Litvin M. Y., Litvin M. Y., Litvin M. More Citation Formats Harvard Chicago IEEE AIP ДСТУ 8302:2015 ДСТУ ГОСТ 7.1:2006 (ВАК) ISO 690:2010 BibTeX на сайт ДП «КБ «Південне»
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3. Selection of Optimal Trajectories of Spacecraft Launch Vehicles

Organization:

Yangel Yuzhnoye State Design Office, Dnipro, Ukraine1; Oles Honchar Dnipro National University, Dnipro, Ukraine2

Page: Kosm. teh. Raket. vooruž. 2016 (2); 17-29

Language: Russian

Annotation: An analysis of the existing methods of trajectories selection of spacecraft launch vehicles is performed. A generalized method is proposed for selection of optimal flight trajectories of launch vehicles in the central gravitational field when launching the artificial earth satellites.

Key words:

Bibliography:
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3.2.2016 Selection of Optimal Trajectories of Spacecraft Launch Vehicles
3.2.2016 Selection of Optimal Trajectories of Spacecraft Launch Vehicles
3.2.2016 Selection of Optimal Trajectories of Spacecraft Launch Vehicles
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