From 1993 to 1997, the Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine published an interdepartmental collection of papers entitled Tekhnicheskaya Mekhanika, which in September 1997 received the status of a scientific journal entitled Tekhnicheskaya Mekhanika (in Russian) and Tekhnichna Mekhanika (in Ukrainian). In 2017, the institute was issued a new state registration certificate for the journal, in accordance with which the journal has the official English title of Technical Mechanics, may publish papers in English, and is entitled to international distribution. The journal publishes review and research articles on the following topics: 1.Applied Mechanics 2. Applied Mathematics 3. Aviation and Space Engineering 4. Automation and Computer-Integrated Technologies 5. Physics and Astronomy
TWO-CRITERIA OPTIMIZATION OF SEQUENTIAL ROUTES OF MULTI-TARGET LOW-ORBIT SERVICE AND SPACE DEBRIS REMOVAL MISSIONS
DOI: https://doi.org/10.15407/itm2025.03.087 In order to ensure the sustainability of the space ecosystem, new types of missions are being developed, such as on-orbit servicing missions (OOS) and active debris removal (ADR) missions. The use of OOS and ADR in low-Earth orbits has a great potential. However, their implementation faces significant problems. Only a few successful OOS missions have been launched and operated in recent decades, while ADR missions have not yet been implemented in orbit. Therefore, the study of the problems associated with the justification and preplanning of OOS and ADR missions is important to improving our understanding of these operations and their effectiveness. The implementation of OOS and ADR is closely related to the efficiency of performing a sequence of orbital maneuvering tasks under conditions of limited energy capabilities of the servicer. The values of the efficiency indices for different OOS and ABC routes may differ significantly. Methods for optimizing the routes of multi-purpose OOS and ADR missions have already been developed and are being developed. The existing literature is mainly focused on finding solutions aimed at minimizing the energy consumption of OOS and ADR missions and reducing their total duration because these factors are considered the most significant in mission planning. Much less attention is paid to optimizing OOS and ADR routes based on the flight safety criterion, which significantly affects the cost of mission insurance. This calls for the development of prompt methods for the multicriteria optimization of OOS and ADR routes taking into account the flight safety criterion. The goal of this work is to develop a prompt method for the two-criteria optimization of sequential routes for multi-purpose OOS and ADR missions performed by a servicer with propulsion units of low constant thrust. The problem is formulated as a two-criteria orbital traveling salesman problem. The methods of solving the problem are multicriteria genetic Pareto optimization, averaging of differential equations, and analytical simulation of servicer orbit transfers. The use of a genetic Pareto optimization algorithm made it possible to avoid local optimal solutions and determined the adopted computational costs. A significant reduction in computational costs was also achieved by using analytical simulation of orbit transfers of a servicer with propulsion units of low constant thrust. The novelty of the obtained results lies in the development of a prompt method for the two-criteria optimization of sequential routes of multi-purpose OOS and ADR missions. The method is easily extendable to a larger number of estimation criteria. The results of this work may be used in the justification and preplanning of OOS and ADR missions in low-Earth orbits. REFERENCES 1. Ceif M. Multiple space debris collecting mission-debris selection and trajectory optimization. Journal of Optimization Theory and Applications. 2013. V. 156. No. 3. Pp. 761-796. https://doi.org/10.1007/s10957-012-0130-6 2. Murakami J., Hokamoto S. Approach for optimal multi-rendezvous trajectory design for active debris removal. 61st International Astronautical Congress IAC. 2010. Pp. 6013-6018. 3. Federici L., Zavoli A., Colasurdo G. et al. Impulsive multi-rendezvous trajectory design an optimization. 8th European Conference for Aeronautics and Space Sciences (EUCASS). 2019. Pp. 1 -4. 4. Jorgensen M. K., Sharf I. Optimal planning for a multiple space debris removal mission using high-accuracy low-thrust transfers. Acta Astronautica. 2020. V. 172. Pp. 56-69. https://doi.org/10.1016/j.actaastro.2020.03.031 5. Shen H.-X., Zhang T.-J. Casalino L., Pastrone D. Optimization of active debris removal missions with multiple targets. Journal of Spacecraft and Rockets. 2018. V. 55. No. 1, Pp 181-189. https://doi.org/10.2514/1.A33883 6. Di Carlo M., Romero Martin J. M., Vasile M. Automatic trajectory planning for low-thrust active removal mission in low-earth orbit. Advances in Space Research. 2017. V. 59. No. 5. Рp. 1234-1258. https://doi.org/10.1016/j.asr.2016.11.033 7. Yang J., Hu Y. H., Liu Y., Pan Q. A maximal-reward preliminary planning for multi-debris active removal mission in LEO with a greedy heuristic method. Acta Astronautica. 2018. V. 149. Pp. 123-142. https://doi.org/10.1016/j.actaastro.2018.05.040 8. Barea A., Urrutxua H., Cadarso L. Large-scale object selection and tra¬jectory planning for multi-target space debris removal missions. Acta Astronautica. 2020. V. 170. Pp. 289-301. https://doi.org/10.1016/j.actaastro.2020.01.032 9. Rossi A., Valsecchi G., Alessi E. The criticality of spacecraft index. Advances in Space Research. 2015. V. 56. No. 3. Pp. 449-460. https://doi.org/10.1016/j.asr.2015.02.027 10. Kechichian J. A. Reformulation of Edelbaum's low-thrust transfer problem using optimal control theory. Journal of Guidance, Control, and Dynamics. 1997. V. 20. No. 5. Pp. 988-994. https://doi.org/10.2514/2.4145 11. Zhang S., Han C., Sun X. New solution for rendezvous between geosynchronous satellites using low thrust. Journal of Guidance, Control, and Dynamics. 2018. V. 41. No. 3. Pp. 1397-1406. https://doi.org/10.2514/1.G003270 12. Han C., Zhang S., Wang X. On-orbit servicing of geosynchronous satellites based on low-thrust transfers considering perturbations. Acta Astronautica. 2019. V.159. Pp. 658-675. https://doi.org/10.1016/j.actaastro.2019.01.041 13. Holdshtein Yu. M. On the choice of a parking orbit for a service spacecraft. The. Meh. 2020. No. 3. Pp. 30 - 38. (in Ukrainian). https://doi.org/10.15407/itm2020.03.030 14. Edelbaum T. N. Propulsion requirements for controllable satellites. ARS Journal. 1961. V. 31. Pp. 1079-1089. https://doi.org/10.2514/8.5723 15. Korbut А. А., Finkelshtein Yu. Yu. Discrete Programming. Nauka, 1969. 368 pp. (In Russian). 16. Popovici N. Pareto reducible multicriteria optimization problems. A Journal of Mathematical Programming and Operations Research. 2005. V. 54. Iss. 3. Pp. 253-263. https://doi.org/10.1080/02331930500096213 17. Kim I. Y., de Weck O. L. Adaptive weighted-sum method for bi-objective optimization: Pareto front generation. Structural and multidisciplinary optimization. 2005. V. 29. Pp. 149-158. https://doi.org/10.1007/s00158-004-0465-1
MICROWAVE METHODS OF EARTH REMOTE SENSING AND THE PROSPECTS FOR THEIR USE
DOI: https://doi.org/10.15407/itm2025.03.098 Microwave remote sensing (RS) allows one to obtain information at any time of day, regardless of solar illumination and in a wide range of meteorological conditions, which gives it an advantage over Earth RS methods using the optical and thermal ranges of electromagnetic radiation. At the same time, the potentialities of microwave methods are not fully utilized in commercial RS spacecraft. This paper analyzes trends in the development of microwave RS aimed at identifying the prospects for the use of these methods in commercial RS satellite constellations. Microwave radiometry, altimetry, scatterometry, and radar imaging are considered. It is shown that, due to government contracts, microwave radiometers will be massively used onboard U.S. small commercial weather satellites in the next few years. On-orbit testing of hyperspectral microwave radiometers, which are also of interest for national security and defense applications, may be expected in the coming years. The use of radar altimeters and scatterometers onboard small satellites is currently technically possible, but not in demand. These instruments are designed primarily for monitoring the ocean surface. The onboard use of altimeters and scatterometers may be caused by the needs of military meteorology and the need to improve the quality of weather forecasts in maritime theaters of war. The most actively developing line of microwave RS is space imagery using synthetic aperture radars. In the last decade, single large-size reconnaissance radar satellites have been replaced by multi-satellite constellations of small spacecraft. Of special interest is the development of operational digital models of the Earth's surface as one of the new areas of radar data application. A transition to higher-frequency bands for imaging, which has been outlined in a number of Chinese companies, will make it possible to achieve a higher spatial resolution at a lower cost. REFERENCES 1. Khramov D. O., Pyrozhenko O. O. Optical methods of earth remote sensing and prospects for their use in commercial spacecraft. Teh. Meh. 2024. No. 4. Pp. 17-30. (In Ukrainian). https://doi.org/10.15407/itm2024.04.017 2. Spencer R. W., Christy J. R. Precision Lower stratospheric temperature monitoring with the MSU: Technique, validation, and results 1979-1991. Journal of Climate. 1993. V. 6. No. 6. Pp. 1194-1204. https://doi.org/10.1175/1520-0442(1993)006<1194:PLSTMW>2.0.CO;2 3. Hollinger J. P., Peirce J. L., Poe G. A. SSM/I instrument evaluation. IEEE Transactions on Geoscience and Remote Sensing. 1990. V. 28. No. 5. Pp. 781-790. https://doi.org/10.1109/36.58964 4. Encyclopedia of Remote Sensing / ed. E. G. Njoku. New York, Springer-Verlag, 2014. 5. Gaiser, P. W. et al. The WindSat spaceborne polarimetric microwave radiometer: sensor description and early orbit performance. IEEE Transactions on Geoscience and Remote Sensing. 2004. V. 42. No. 11. Pp. 2347-2361. https://doi.org/10.1109/TGRS.2004.836867 6. Lambrigtsen B. et al. Getting the GeoSTAR instrument concept ready for a space mission, 2011. URL: https://esto.nasa.gov/conferences/estf2011/presentations/Lambrigsten_ESTF2011.pdf (Last accessed on July 4, 2025). 7. Ramos-Perez I. et al. PAU-SA: A synthetic aperture interferometric radiometer test bed for potential improvements in future missions. Sensors. 2012. V. 12. No. 6. Pp. 7738-7777. https://doi.org/10.3390/s120607738 8. Maeda T. et al. Direct RF Sampling hyperspectral microwave radiometer (DSμRAD) for ground use. IEEE Geoscience and Remote Sensing Letters. 2021. V. 8. No. 6. Pp. 1084-1088. https://doi.org/10.1109/LGRS.2020.2990707 9. Maeda T., Kawaguchi N., Tomii N. Demonstration of ultrawideband hyperspectral microwave interferometer by true time delay. IEEE Geoscience and Remote Sensing Letters. 2022. V. 19. Pp. 1-5. https://doi.org/10.1109/LGRS.2020.3023697 10. Henry M. et al. Development of a hyperspectral microwave sounder for enhanced weather forecasting. IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium. 2023. Pp 1092-1095. https://doi.org/10.1109/IGARSS52108.2023.10282436 11. Liu L. et al. Radiative closure tests of collocated hyperspectral microwave and infrared radiometers. Atmospheric Measurement Techniques. 2024. No. 17. Pp. 2219-2233. https://doi.org/10.5194/amt-17-2219-2024 12. Brown S. et al. Demonstrating a low-cost sustainable passive microwave sensor architecture: The Compact Ocean Wind Vector Radiometer Mission. 2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS). 2016. Pp. 5561-5564. https://doi.org/10.1109/IGARSS.2016.7730452 13. Padmanabhan S. et al. TEMPEST-D Radiometer: Instrument description and prelaunch calibration. IEEE Transactions on Geoscience and Remote Sensing. 2020. Pp. 1-14. 14. Foy K. Lincoln Laboratory honored for technology transfer of hurricane-tracking satellites. URL: https://www.ll.mit.edu/news/lincoln-laboratory-honored-technology-transfer-hurricane-tracking-satellites (Last accessed on July 4, 2025). 15. Yang L. et al. Satellite altimetry: Achievements and future trends by a scientometrics analysis. Remote Sensing. 2022. V. 14. P. 3332. https://doi.org/10.3390/rs14143332 16. Rosmorduc V. et al. The first 25 years of altimetry outreach. Advances in Space Research. 2021.V. 68. No. 2. Pp. 1225-1241. https://doi.org/10.1016/j.asr.2020.08.026 17. Srinivasan M., Tsontos V. Satellite altimetry for ocean and coastal applications: A review. Remote Sensing. 2023. V. 15. No. 16. P. 3939. https://doi.org/10.3390/rs15163939 18. Gelsthorpe R. V., Schied E., Wilson J. J. W. ASCAT - Metop's advanced scatterometer. 2000. URL: https://www.esa.int/esapub/bulletin/bullet102/Gelsthorpe102.pdf (Last accessed on July 4, 2025). 19. SCATSAT-1 Level 4 Data Products Format Document. 2017. URL: https://mosdac.gov.in/docs/scatsat_level4_dataproducts.pdf (Last accessed on July 4, 2025). 20. Li H. et al. Design of a new sensor integrating scatterometer and SAR to observe sea surface wind field. 2021 CIE International Conference on Radar (Radar). 2021. Pp. 2990-2993. https://doi.org/10.1109/Radar53847.2021.10028170 21. Martin A. C. H. et al. Performance of the Earth Explorer 11 SeaSTAR Mission candidate for simultaneous retrieval of total surface current and wind vectors. Remote Sensing, 2024. V. 16. No. 19. P. 3556. https://doi.org/10.3390/rs16193556 22. Frison P. L., Jarlan L., Mougin E. Using satellite scatterometers to monitor continental surfaces. Land Surface Remote Sensing in Continental Hydrology. 2016. P. 79-113. https://doi.org/10.1016/B978-1-78548-104-8.50003-6 23. Lillesand T.M., Kiefer R.W., Chipman J. Remote Sensing and Image Interpretation (7th edition). Wiley, 2015. 24. SAR Handbook: Comprehensive Methodologies for Forest Monitoring and Biomass Estimation / eds. Flores A. et al. NASA. 2019. URL: https://servirglobal.net/Global/Articles/Article/2674/sar-handbook-comprehensive-methodologies-for-forest-monitoring-and-biomass-estimation (Last accessed on July 4, 2025). 25. Ti J. et al. A Novel SAR Imaging method for GEO satellite-ground Bistatic SAR system with severe azimuth spectrum aliasing and 2-D spatial variability. Remote Sensing. 2024. V. 16. No .15. P. 2853. https://doi.org/10.3390/rs16152853 26. Yan W. et al. design and on-orbit performance of Ku-band phased-array synthetic-aperture radar payload system. Sensors. 2024. V. 24. No. 20. P. 6741. https://doi.org/10.3390/s24206741 27. Yang R. et al. Polarimetric Microwave Imaging. Springer, 2021. https://doi.org/10.1007/978-981-15-8897-6 28. Fan Q. et al. Ship detection using a fully convolutional network with compact polarimetric SAR images. Remote Sensing. 2019. V. 11. No. 18. P. 2171. https://doi.org/10.3390/rs11182171 29. Paek S. et al. Small-satellite synthetic aperture radar for continuous global biospheric monitoring: A review. Remote Sensing. 2020. V. 12. No. 16. P. 2546. https://doi.org/10.3390/rs12162546 30. Guccione P. et al. Along-track multistatic synthetic aperture radar formations of minisatellites. Remote Sensing. 2020. V. 12. No. 1. P. 124. https://doi.org/10.3390/rs12010124 31. Sommervold O., Gazzea M., Arghandeh R. A survey on SAR and optical satellite image registration. Remote Sensing. 2023. V. 15. No. 3. P. 850. https://doi.org/10.3390/rs15030850 32. Arumugam D. et al. Remote sensing of soil moisture using Rydberg atoms and satellite signals of opportunity. Scientific Reports. 2024. V. 14. No. 1. 18025. https://doi.org/10.1038/s41598-024-68914-6
RESONANCE PARAMETRIC VIBRATIONS OF A CYLINDRICAL SANDWICH SHELL
DOI: https://doi.org/10.15407/itm2025.03.046 This paper considers cylindrical composite sandwich shells that consist of two thin outer layers and one thick honeycomb filler. The outer layers are made of a composite orthotropic material, for example, carbon-reinforced plastic. The honeycomb filler is made of an orthotropic plastic, for example, PLA, using additive technologies. To obtain a mathematical model of nonlinear structural vibrations, the honeycomb core is homogenized into a uniform orthotropic solid layer using a finite-element simulation in ANSYS. Parametric vibrations of the cylindrical shell under the action of a longitudinal load are considered. Each layer of the structure is described by a higher-order shear theory, which uses five generalized displacements (three displacements projections onto the axes and two rotation angles of the middle surface normal). The displacement projections are continuous at the layer interfaces. The assumed mode method is used to obtain a system of nonlinear ordinary differential equations in the generalized coordinates. The method uses the kinetic and the potential energy of the structure. The shooting technique and the parameter continuation method are used jointly to analyze nonlinear vibrations, their stability and bifurcations. The multipliers are calculated to estimate the vibration stability. The stability and bifurcations of periodic oscillations are shown in the frequency responses, which describe the structure dynamics in the principal parametric resonances. As shown by the numerical analysis, standing waves are observed in the cylindrical shell. As a result of the bifurcations, the standing waves are transformed into travelling ones, which are described by a loop in the frequency response. REFERENCES 1. Karimiasl M., Ebrahimi F., Mahesh V. Nonlinear forced vibration of smart multiscale sandwich composite doubly curved porous shell. Thin Wall. Struct. 2019. V. 143. 106152. https://doi.org/10.1016/j.tws.2019.04.044 2. Karimiasl M., Ebrahimi F. Large amplitude vibration of viscoelastically damped multiscale composite doubly curved sandwich shell with flexible core and MR layers. Thin Wall. Struct. 2019. V. 144. 106128. https://doi.org/10.1016/j.tws.2019.04.020 3. Yadav A., Amabili M., Panda S. K., Dey T., Kumar R. Forced nonlinear vibrations of circular cylindrical sandwich shells with cellular core using higher-order shear and thickness deformation theory. J. Sound Vib. 2021. V. 510. 116283. https://doi.org/10.1016/j.jsv.2021.116283 4. Cong P. H., Khanh N. D., Khoa N. D., Duc N. D. New approach to investigate nonlinear dynamic response of sandwich auxetic double curves shallow shells using TSDT. Compos. Struct. 2018. V. 185. Pp. 455-465. https://doi.org/10.1016/j.compstruct.2017.11.047 5. Zhang Y., Li Y. Nonlinear dynamic analysis of a double curvature honeycomb sandwich shell with simply supported boundaries by the homotopy analysis method. Compos. Struct. 2019. V. 221. 110884. https://doi.org/10.1016/j.compstruct.2019.04.056 6. Quyen N. V., Thanh N. V., Quan T. Q., Duc N. D. Nonlinear forced vibration of sandwich cylindrical panel with negative Poisson's ratio auxetic honeycombs core and CNTRC face sheets. Thin Wall. Struct. 2021. V. 162. 107571. https://doi.org/10.1016/j.tws.2021.107571 7. Li C., Shen H.-S., Wang H., Yu Z. Large amplitude vibration of sandwich plates with functionally graded auxetic 3D lattice core. Int. J. Mech. Sci. 2020. V. 174. 105472. https://doi.org/10.1016/j.ijmecsci.2020.105472 8. Goncalves B. R., Jelovica J., Romanoff J. A homogenization method for geometric nonlinear analysis of sandwich structures with initial imperfections. Int. J. Solids Struct. 2016. V. 87. Pp. 194-205. https://doi.org/10.1016/j.ijsolstr.2016.02.009 9. Yongqiang L., Feng L., Yongliang H. Geometrically nonlinear forced vibrations of the symmetric rectangular honeycomb sandwich panels with completed clamped supported boundaries. Compos. Struct. 2011. V. 93. Pp. 360-368. https://doi.org/10.1016/j.compstruct.2010.09.006 10. Li Y., Zhou M., Wang T., Zhang Y. Nonlinear primary resonance with internal resonances of the symmetric rectangular honeycomb sandwich panels with simply supported along all four edges. Thin Wall. Struct. 2020. V. 147. 106480. https://doi.org/10.1016/j.tws.2019.106480 11. Malekzadeh P. A differential quadrature nonlinear free vibration analysis of laminated composite skew thin plates. Thin Wall. Struct. 2007. V. 45. Pp. 237-250. https://doi.org/10.1016/j.tws.2007.01.011 12. Chen X., Feng Z. Dynamic behaviour of a thin laminated plate embedded with auxetic layers subject to in-plane excitation. Mech. Res. Commun. 2017. V. 85. Pp. 45-52. https://doi.org/10.1016/j.mechrescom.2017.07.013 13. Catapano A., Montemurro M. A multi-scale approach for the optimum design of sandwich plates with honeycomb core. Part I: homogenisation of core properties. Compos. Struct. 2014. V. 118. Pp. 664-676. https://doi.org/10.1016/j.compstruct.2014.07.057 14. Amabili M. Non-linearities in rotation and thickness deformation in a new third-order thickness deformation theory for static and dynamic analysis of isotropic and laminated doubly curved shells. Int. J. Nonlin. Mech. 2015. V. 69. Pp. 109-128. https://doi.org/10.1016/j.ijnonlinmec.2014.11.026 15. Parker T. S., Chua L. O. Practical Numerical Algorithms for Chaotic Systems. Berlin: Springer. 1989. 348 pp. https://doi.org/10.1007/978-1-4612-3486-9
METHOD FOR PROJECT RANKING BY QUANTITATIVE AND QUALITATIVE CRITERIA
DOI: https://doi.org/10.15407/itm2025.03.063 Determining the efficiency and priority of R&D projects has always been topical and important. It has been widely considered by numerous home and foreign researchers. However, the problem of project evaluation by preference in a multidimensional space of heterogeneous criteria has not been adequately addressed yet. The main goal of this paper is to present a method of project ranking by quantitative and qualitative criteria based on a consistent criteria scaling algorithm and to demonstrate its applicability. The consistent scaling algorithm (CSA) is a variant of the familiar algorithms of joint criteria scaling. As distinct from an independent scaling algorithm (ISA), which is used in the construction of an additive integral value function (IVF) in normalized form, the CSA is used in the construction of a canonical IVF. These algorithms are based on methods of multi-attribute utility theory, which use the operation of trading off one quality index against another. The classical CSA and ISA have a resolution equal to one, but they operate with qualitative criteria alone, thus considerably narrowing their field of application. To resolve this problem, the tradeoff operation of replacement in the CSA was modified, and a special procedure was proposed for joint scaling of heterogeneous criteria. Based thereon, stage-by-stage procedures were developed to construct local value functions both for qualitative and for quantitative criteria. As a result, the following problems were solved. A method was proposed to verify the preferential independence of qualitative criteria. By modifying the CSA, the problem of incomparability of heterogeneous criteria was overcome. An additive model of a canonical IVF was constructed for heterogeneous criteria, and several methods to verify the IVF for adequacy were proposed, including a constructive verification, which allows one to formally identify inadequate models. A method was developed to rank alternatives in a space of quantitative and qualitative criteria with a maximum resolution. This work used methods of decision-making theory, multi-attribute utility theory, and verbal analysis of solutions. The obtained results may be used in evaluating the efficiency of innovative technologies, in project competitions, and in R&D program formation, thus improving project management quality and allowing one to justify project advisability. REFERENCES 1. Von Neumann J, Morgenstern O. Theory of Games and Economic Behavior. Translation from English into Russian, N. N. Vorob'ev (Ed.). Moscow: Nauka, 1974. 708 pp. (In Russian). 2. Keeney R. L., Raifa H. Decision Making with Multiple Objectives: Preferences and Value Tradeoffs. Moscow: Radio i Svyas, 1981. 560 pp. (In Russian). 3. Nikolaev V. I., Bruk V. M. Systems Engineering: Methods and Applications. Leningrad: Mashinostroyeniye, 1985. 199 pp. (In Russian). 4. Totsenko V. G. Methods and Systems of Decision Making Support. Algorithmic Aspect. Kyiv: Naukova Dumka, 2002. 381 pp. (In Russian). 5. Larichev O. I. Decision Making Theory and Methods and Chronicle of Events in Wonderlands. Moscow: Logos, 2006. 392 pp. (In Russian). 6. Petrovsky A. B. Decision Theory. Moscow: Academia, 2009. 400 pp. (In Russian). 7. Larichev O. I., Prokhorov A. S., Petrovsky A. B. et al. Experience in fundamental research planning on a competitive basis. Vestnik AN SSSR. 1989. No. 7. Pp. 51-61. (In Russian). 8. Pylypenko O. V., Pereverzev E. S., Marchenko V. T., Khorolskyi P. P., Pechenevskaya O. K. Effectiveness of R&D Projects and Programs. Dnipropetrovsk: Porogi, 2008. 509 pp. (In Russian). 9. Petrovsky A. B., Roizenzon G. V., Tykhonov I. P., Balyshev A. V. Multicriteria approach to research project effectiveness evaluation. Bulletin of the National Technical University "KhPI," Information and Modeling. 2009. No. 43. Pp. 138-148. (In Ukrainian). 10. Voronin A. Multi-criteria evaluation of space activity projects. International Journal Information Technologies & Knowledge. 2014. V. 8. Nо. 1. Рp. 14-21. 11. Beskorovainy V. V., Moskalenko A. S., Podolyaka K. E. Multifactor evaluation of large-scale object reengineering based on comparative identification. Elektrotekhnicheskiye i Kompyuternye Sistemy. 2016. No. 23 (99). Pp. 192-200. (In Russian). https://doi.org/10.15276/eltecs.23.99.2016.30 12. Kolpakov V. M. Theory and Practice of Managerial Decision Making. Kyiv: MAUP, 2004. 504 pp. (In Russian). 13. Manchuk V. M. Determination of the priority of R&D projects using a criteria scaling algorithm. Teh. Meh. 2020. No. 1. Pp. 91-105. (In Ukrainian). https://doi.org/10.15407/itm2020.01.091 14. Mamchuk V. M. Construction of a multiplicative-additive criteria convolution in the space of quantitative and qualitative indices to determine the priority of projects. Teh. Meh. 2022. No. 1. Pp. 77-90. (In Ukrainian). https://doi.org/10.15407/itm2022.01.077 15. Glotov V. A., Pavel'ev V. V. Vector Stratification. Moscow: Nauka, 1984. 94 pp. (In Russian). 16. Aivazyan S. A., Bukhshtaber V. M., Enyukov I. S., Meshalkin L. D. Applied Statistics. Classification and Dimension Reduction. Moscow: Finansy i Statistika, 1989. 607 pp. (In Russian). 17. Larichev O. I. Verbal Decision Analysis. Moscow: Nauka, 2006. 181 pp. (In Russian). 18. Petrovsky A. B., Roizenzon G. V. Interactive procedure for attribute space dimension reduction in imulti-criteria classification problems. Decision-making support. Proceedings of the Institute for Systems Analysis Russian Academy of Sciences. Moscow: Editorial URSS, 2008. V. 35. Pp. 43-53. (In Russian). 19. Kondruk N. E., Maliar M. M. Multi-Criteria Optimization of Linear Systems. Uzhрorod: Outdoor Shark, 2019. 76 pp. (In Ukrainian). 20. Petrov E. G., Shilo N. S. Procedure for assessing the adequacy of models of a decision-maker's individual preference pointwise identification. Radioelektronika i Informatika. 2003. No. 2. Pp. 97-103. (In Russian). 21. Larichev O. I., Moshkovich E. M. Qualitative Methods of Decision-Making. Verbal Decision Analysis. Moscow: Nauka, 1996. 208 pp. (In Russian).
ESTIMATION OF THE DEORBIT TIME OF SPACECRAFT AND SPACE DEBRIS FROM LEO
DOI: https://doi.org/10.15407/itm2025.03.078 The goal of this article is to develop a procedure for estimating the deorbit time of used spacecraft and space debris from a nearly circular low-Earth orbit. The paper presents, in a convenient for practical calculations form, an equation of motion of a body along a circular orbit under the action of the atmospheric drag and a given active force. At the observation stage, available online data on the orbit altitude and a model atmospheric density allow one to approximate the ballistic coefficient of the body, which is nearly always unknown in practice. At the estimation stage, the deorbit process is calculated using the approximate ballistic coefficient found previously. The deorbit time calculation error is determined as a function of the duration of the observation and estimation stages for different atmospheric models. The proposed procedure allows one to estimate the minimum acceleration to deorbit the body in a given time. The procedure is validated by calculating the deorbit time of a spacecraft whose uncontrolled flight lasted 16 years: the error is about 10 per cent of the actual deorbit time. The proposed procedure may be used in estimating the life time of space debris objects and in planning the active deorbit of spacecraft at the end of their service life. The proposed procedure may be a basis for future development with account for other interactions between an orbiting body and the space environment. REFERENCES 1. European Space Agency. ESA Space Debris Mitigation Requirements, ESSB-ST-U-007, Issue 1. 83 pp. URL: https://technology.esa.int/upload/media/ESA-Space-Debris-Mitigation-Requirements-ESSB-ST-U-007-Issue1.pdf (Last accessed on January 23, 2025). 2. State-of-the-Art Small Spacecraft Technology. NASA Ames Research Center, Small Spacecraft Systems Virtual Institute. Moffett Field, CA 94035-1000. 416 pp. URL: https://www.nasa.gov/wp-content/uploads/2025/02/soa-2024.pdf (Last accessed on February 12, 2025). 3. ESA's Annual Space Environment Report. 144 pp. URL: https://www.sdo.esoc.esa.int/environment_report/Space_Environment_Report_latest.pdf (Last accessed on February 6, 2025). 4. ESA-DRAMA: Debris Risk Assessment and Mitigation Analysis. URL: https://sdup.esoc.esa.int/drama/downloads/setup/3.1.1/setup_DRAMA-3.1.1_windows.exe (Last accessed on February 6, 2025). 5. Miyata K., Kawashima R., Inamori T. Detailed analysis of aerodynamic effect on small satellites. Transactions of The Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan. 2018. V. 16. Iss. 5. Рp. 432-440. https://doi.org/10.2322/tastj.16.432 6. Montenbruck O., Gill E. Satellite Orbits: Models, Methods, and Applications. Berlin Heidelberg: Springer, 2000. 369 pp. https://doi.org/10.1007/978-3-642-58351-3 7. URL: https://ccmc.gsfc.nasa.gov/models/ (Last accessed on February 18, 2025). 8. Mutschler S., Tobiska W., Pilinski M. et al. A Survey of Current Operations-Ready Thermospheric Density Models for Drag Modeling in LEO Operations. AMOS Conference, Maui, HI, USA, October 2023. URL: https://www.researchgate.net/publication/374998825 (Last accessed on February 18, 2025). 9. Picone J. M., Hedin A. E., Drob D. P., Aikin A. C. NRLMSISE-00 empirical model of the atmosphere: Statistical comparison and scientific issues. J. Geophys. Res. 2002. V. 107. Pp. 1-15. https://doi.org/10.1029/2002JA009430 10. URL: https://celestrak.org (Last accessed on February 18, 2025). 11. ECSS-E-ST-10-04C Rev.1 - Space environment. 208 pp. URL: https://ecss.nl/standard/ecss-e-st-10-04c-rev-1-space-environment-15-june-2020/ (Last accessed on February 20, 2025). 12. Braun V., Flegel S., Gelhaus J. at al. Impact of solar flux modeling on satellite lifetime predictions. 63rd International Astronautical Congress, Naples, Italy, October 2012. URL: https://www.researchgate.net/publication/271729675 (Last accessed on February 20, 2025). 13. URL: https://static.sdo.esoc.esa.int/SOLMAG/long_term.dat (Last accessed on February 20, 2025). 14. URL: https://en.wikipedia.org/wiki/Earth_Radiation_Budget_Satellite (Last accessed on February 20, 2025).
VELOCITY INTEGRAL BRACKETS FOR A ONE-COMPONENT SYSTEM WITH SMALL INTERACTION
DOI: https://doi.org/10.15407/itm2025.03.114 The standard and widely used approach to the description of the hydrodynamic stage of the system evolution is the Chapman–Enskog method, in the framework of which the system distribution function is calculated in a perturbation theory in small gradients. The system kinetic coefficients are calculated on the basis of the obtained first-order-in-gradients distribution function, the temperature and velocity parts of which are the solutions of Fredholm integral equations of the first kind. In the literature it is considered that the standard approach to the solution of the corresponding integral equations is an approximate search for their solution with the help of the Galerkin method based on an artificially truncated Sonine polynomial expansion. The so-called integral brackets are needed in order to calculate the coefficients multiplying the polynomials, and the calculation of the integral brackets is the most cumbersome stage of the kinetic coefficient calculation. In the literature it is assumed that the solution of a Fredholm equation of the first kind converges fast with increasing number of polynomials, that is why the corresponding analytical solutions are often restricted to the one- or two-polynomial approximations. However, for a number of systems the numerical investigation of the corresponding convergence is made on the basis of the corresponding numerical calculations for many-polynomial approximations. We do not know any works where the corresponding numerical investigation would be provided for a system with small interaction described by the Landau kinetic equation which contains the Landau collision integral. In our previous paper, we calculated the so-called temperature integral brackets for a one-component system with small interaction up to the thirteen-polynomial approximation; the corresponding integral brackets are needed in order to calculate the system thermal conductivity. In this paper, we calculate the so-called velocity integral brackets for a one-component system with small interaction up to the thirteen-polynomial approximation, the corresponding integral brackets are needed in order to calculate the system viscosity. The obtained results are important for a further numerical investigation of the convergence of the solutions for the system thermal conductivity and viscosity with increasing number of polynomials. The corresponding numerical investigation with a detailed calculation of the first-order-in-gradients distribution function may be given in another paper. REFERENCES 1. Akhiezer A. I., Peletminsky S. V. Methods of Statistical Physics. Oxford: Pergamon Press, 1981. 376 pp. 2. Balescu R. Equilibrium and Non-Equilibrium Statistical Mechanics. Malabar: Kreiger Pub Co, 1991. 742 pp. 3. Colangeli M. From Kinetic Models to Hydrodynamics. Some Novel Results. New York: Springer, 2013. 109 pp. https://doi.org/10.1007/978-1-4614-6306-1 4. Gorev V. N., Sokolovsky A. I. One-velocity and one-temperature hydrodynamics of plasma. Visnyk Dnipropetrovskogo Universytetu. Fizyka Radioelectronika. 2013. V. 21. No. 2. Рp. 39-46. 5. Khalil N., Garzo V. Homogeneous states in driven granular mixtures: Enskog kinetic theory versus molecular dynamics simulations. The Journal of Chemical Physics. 2014. V. 140. 164901. https://doi.org/10.1063/1.4871628 6. Gonzalez R. G., Garzo V. Kinetic Theory of binary granular suspensions at low density. Thermal diffusion segregation. In: Brenig L., Brilliantov N., Tlidi, M. (Eds.). Nonequilibrium Thermodynamics and Fluctuation Kinetics. Fundamental Theories of Physics. Cham: Springer, 2022. V. 208. Pp. 173-189. https://doi.org/10.1007/978-3-031-04458-8_9 7. Sokolovsky S. A., Sokolovsky A. I., Hrinishyn O. A. Hydrodynamic states of electron plasma of semiconductors in the generalized Chapman-Enskog method. Journal of Physics and Electronics. 2020. V. 28. No. 1. Pp. 9-16. https://doi.org/10.15421/332002 8. Tipton E. L., Tompson R. V., Loyalka S. K. Chapman-Enskog solutions to arbitrary order in Sonine polynomials II: Viscosity in a binary, rigid-sphere, gas mixture. European Journal of Mechanics B/Fluids. 2009. V. 28. Pp. 335-352. https://doi.org/10.1016/j.euromechflu.2008.09.002 9. Tang J., Chow W., Shizgal B. Nonequilibrium effects for reactions with activation energy: Convergence of the expansions of solutions of the Boltzmann and Lorentz Fokker Planck equations with Sonine and Maxwell polynomials as basis functions. Physica A. 2025. V. 668. 130522. https://doi.org/10.1016/j.physa.2025.130522 10. Gorev V. N., Tytarenko V. V., Turinov A. N., Voronko T. E. Temperature integral brackets for a one-component system with small interaction. Teh. Meh. 2025. No. 2. Pp. 124-134. https://doi.org/10.15407/itm2025.02.124
FEATURES OF THE STRENGTH ANALYSIS OF BOLTED CONNECTIONS BETWEEN LAUNCH VEHICLE COMPARTMENTS
DOI: https://doi.org/10.15407/itm2025.03.003 This work is devoted to the study of the features of the deformation of bolted flange connections of launch vehicle compartments and the determination of failure loads thereon. The goal of the work is to study problematic issues of the correct choice of an analytical model for flange connections of individual compartments. A method for determining the ultimate load on a bolted connection is presented. Finite element analysis methods were used. The calculations meet all the requirements adopted in the field of bolted connection strength standards. Relevant safety factors are also used. Account is taken of bolt thread stripping, unloading sleeve shearing, the bolt tightening force simulated by the introduction of corresponding temperature loads, and other connection member parameters. The results of full-scale destructive tests of the flange connection of the end frames of individual compartments are analyzed. A discrepancy between the calculated results and the test data is found out. It is shown that the discrepancy is due to an insufficiently correct consideration of the design features of the connections and the action of external loads, which led to additional components of eccentric tension-compression. It is demonstrated that the destructive load calculated with account for the “force lever” predictably proved to be smaller than that calculated in the assumption of a rigid frame and close to the full-scale test data. The article also presents the results of a numerical finite element study of the sensitivity of calculated results to variations in the principal bult connection parameters: the bolt tightening forces, the unloading sleeve diameter, the constructive offset of the bolt axes to the middle surface of the compartment shell, etc. The results obtained may be useful as a scientific and methodological basis for the correct choice of analytical models for flange connections of launch vehicle compartments. REFERENCES 1. Balabukh L. I., Alfutov N. A., Usyukin V. I. Structural Mechanics of Rockets. Moscow: Vysshaya Shkola, 1984. 496 pp. (In Russian). 2. Beitsun V. S., Dziuba A. P. Experimental study of the flexibility of flange connections in a space manipulator model. Problems of Computational Mechanics and Strength of Structures. 2024. Iss. 38. Pp. 5–19. (In Ukrainian). 3. Beitsun V. S., Tarasov S.V. Methodology for photogrammetric measurement of backlashes and elastic compliances in hinge joints of transport manipulators and spacecraft booms Teh. Meh. 2024. No. 3. Pp. 124–137. (In Ukrainian). https://doi.org/10.15407/itm2024.03.124 4. Bondarenko D., Krivoruchko A., Khorolskiy P. The development of effective systems for connecting and separating of compartments. Journal of Rocket-Space Technology. 2020. No. 28(4). Pp. 14–20. (In Ukrainian). https://doi.org/10.15421/452002 5. Degtyarev A. V. Rocket Technology. Problems and Prospects. Dnipropetrovsk: ART-PRESS, 2014. 420 pp. (In Russian). 6. Dziuba A. P., Dziuba O. A., Sirenko V. M. Investigation of the sensitivity of the results of calculating the strength of structural elements to variations in input data. Problems of Computational Mechanics and Strength of Structures. 2024. Iss. 39. (In Ukrainian). 7. Lizin V. T., Pyatkin V. A. Design of Thin-Walled Structures. Moscow: Mashinostroyeniye, 1976. 408 p. (In Russian). 8. Manko T. A., Litot A. V. Use of modern software packages in the design and manufacture of carbon fiber propellant tank flanges. System Design and Performance Analysis of Aerospace Hardware. Dnipro: Lira, 2019. Pp. 90–94. 9. Mikulnyk I. O., Karvatskyi A. Ya., Ivanenko O. I., Leleka S. V. Flange connections of equipment and pipelines of chemical technology. Bulletin of NTUU "Igor Sikorsky Kyiv Polytechnic Institute". Series: Chemical Engineering, Ecology and Resource Conservation. 2023. No. 2(22). Pp. 15–31. (In Ukrainian). 10. Mossakovsky V. I., Makarenkov A. G., Nikitin P. I., Savvin Yu. I., Spiridonov I. N. Strength of Rocket Structures. Moscow: Vysshaya Shkola, 1990. 360 pp. (In Russian). 11. Kharchenko V. Modeling and determination of the stress state of joints of rocket structures made of composite materials. Applied Problems of Mechanics and Mathematics, 2017. Iss. 15. Pp. 185–190. (In Ukrainian). 12. Kharchenko V., Klymenko D. Stress loading of rocket joints taking into account the structural features of adjacent compartments. Applied Problems of Mechanics and Mathematics. 2019. Iss.17. P. 98–104. (In Ukrainian). https://doi.org/10.15407/apmm2019.17.98-104 13. Dzyuba A., SirenkoV. Substantiation of reliability of calculation of strength of rocket and space technology structures without destructive tests. Advances in Mechanics. Current Research Results of the NAS of Ukraine. Chapter 12. A.N. Guz, H. Altenbach, V. Bogdanov, V. M. Nazarenko (Eds.). Cham: Springer, 2023. Pp. 212–222. https://doi.org/10.1007/978-3-031-37313-8_12 14. Zienkiewicz O. C., Taylor R. L., Zhu J. Z. The Finite Element Method: Its Basis and Fundamentals. Sixth edition. Butterworth-Heinemann, 2016. 753 pр.
MATHEMATICAL SIMULATION OF AN UNSTEADY LIQUID FLOW IN TANKS AS APPLIED TO THE PROBLEM OF DESCRIPTION OF LIQUID-PROPELLANT ROCKET POGO OSCILLATIONS
DOI: https://doi.org/10.15407/itm2025.03.009 In today’s liquid-propellant launch vehicles (LVs), the propellant mass may exceed 90 % of the total LV mass. When describing longitudinal oscillations in an elastic tank, the propellant is usually simulated by mechanical oscillators. This approach ignores the difference in dynamic processes in the liquid propellant components in the tanks and in the LV structure as an elastic body. The goal of this paper is to account for the features of an unsteady tank liquid flow as applied to the problem of description of liquid-propellant rocket pogo oscillations. An approach is developed to mathematical simulation of unsteady liquid flow in liquid-propellant LV tanks as a distributed-parameter system. Using the impedance method, a nonlinear system of equations is derived to determine the effective sound speed in the tank propellant and the inertia resistance coefficient at the tank outlet. An approach is developed to mathematical simulation of an unsteady liquid flow in liquid-propellant LV tanks as a lumped-parameter system. A lumped-parameter mathematical model is constructed to describe two eigenmodes of the tank liquid oscillations. A system of equations is derived to determine the coefficients of the lumped-parameter model, which uses the effective sound speed and the inertia resistance coefficient at the tank outlet found in the distributed-parameter model. The above approaches are demonstrated by the example of the oxidizer tank of the Cyclone liquid-propellant LV’s first stage. It is shown that the effective sound speed is one seventh of the sound speed in an infinite medium. The inertia resistance coefficient at the tank outlet is far greater than the total inertia resistance coefficient of the tank liquid (early in the flight, by a factor of more than 10). These results show the tank bottom dynamics is of great importance in mathematical simulation of an unsteady tank propellant flow. The model coefficients are determined for the mathematical model of an unsteady liquid flow in the oxidizer tank of the Cyclone liquid-propellant lV’s first stage as a lumped-parameter system from the condition of agreement with a known solution on tank liquid eigenfrequencies. REFERENCES 1. Degtyarev A. V. Rocket Engineering. Problems and Prospects. Dnipropetrovsk: ART-PRESS, 2014. 420 pp. (In Russian). 2. Pylypenko O. V., Dolgopolov S. I., Nikolayev O. D., Khoriak N. V. Mathematical modeling of the transient processes in propulsion system of the upper stage of the Cyclone-4M launch vehicle. Science and Innovation. 2024. Vol. 20, No. 1. Pp. 49–67. 3. Dolgopolov S., Nikolayev O. Features of mathematical modeling of nonlinear Pogo oscillations of launch vehicles. CEAS Space Journal. 2024. V. 16. Iss. 2. Pp. 32–48. https://doi.org/10.1007/s12567-024-00541-3 4. Kolesnikov K. S. Rocket Dynamics. Moscow: Mashinostroyeniye, 1980. 378 pp. (In Russian). 5. Abgaryan K. A., Kalyazin E. L., Mishin V. P., Rappoport I. M. Rocket Dynamics. Moscow: Mashinostroyeniye, 1990. 464 pp. (In Russian). 6. Mikishev G. N., Rabinovich B. I. Dynamics of a Solid Body with Cavities Partially Filled with a Liquid. Moscow: Mashinostroyeniye, 1968. 532 pp. (In Russian). 7. Narimanov G. S., Dokuchaev L. V., Lukovsky I. A. Nonlinear Dynamics of a Flying Vehicle with a Liquid. Moscow: Mashinostroyeniye, 1977. 208 pp. (In Russian). 8. Nikolayev A. D., Bashliy I. D. Mathematical simulation of spatioal oscillations of a liquid in longitudinally vibrating tank. Teh. Meh. 2012. No. 2. Pp. 14–22. (In Russian). 9. Bashliy I. D., Nikolayev A. D. Mathematical simulation of spatial vibrations of shell structures with a liquid using up-to-date means of computer-aided design and analysis. Teh. Meh. 2013. No. 2. Pp. 18–25. (In Russian). 10. Nikolayev A. D., Khoriak N. V. Characterization of longitudinal self-oscillations of the liquid-propellant launch vehicle structure with account for energy dissipation. Aviatsionno-Kosmicheskaya Tekhnika i Tekhnologiya. 2004. No. 4. Pp. 62–73. (In Russian). 11. Wiggert D. C., Otwell R. S, Hatfield F. J. The effect of elbow restraint on pressure transients. ASME J. Fluids Eng. 1985. V. 107. Pp. 402–406. https://doi.org/10.1115/1.3242500 12. Pilipenko V. V., Zadontsev V. A., Natanzon M. S. Cavitation Oscillations and Hydrosystem Dynamics. Moscow: Mashinostroyeniye, 1977. 352 pp. (In Russian). 13. Altshul A. D. Hydraulic Resistances. Moscow: Nedra, 1970. 216 pp. (In Russian). 14. Zhulai Yu. A., Dolgopolov S. I., Grabovskaya T. A. Mathematical simulation of joint longitudinal pipeline structure - liquid oscillations under cavitation oscillations in liquid-propellant rocket engine feed lines. Aviatsionno-Kosmicheskaya Tekhnika i Tekhnologiya. 2009. No. 5(62). Pp. 58–63. (In Russian).
EFFECT OF THE DISTANT POSITION OF A PROPELLANT VALVE ON THE STARTUP DELAY OF A “GREEN”-PROPELLANT THRUSTER
DOI: https://doi.org/10.15407/itm2025.03.021 In recent years, the leading space countries have paid much attention to a search for and the application of new toxically safe propellants for spacecraft thrusters. A water solution of an ion substance, a fuel, and a stabilizer is used as a “green” propellant. Its feature is a significant increase in the temperature in the thruster reaction chamber in comparison with traditional propellants. Electrically driven propellant valves, which control fuel feed to the reaction chamber in response to thruster startup and shutdown signals, are connected to the reaction chamber via an additional propellant pipeline to provide thermal conditions required for the valve operation. This design solution is responsible for an additional delay between a command signal and a thruster startup, thus complicating the operation of the spacecraft control system. The propellant feed time must be calculated with account for a low pressure in the pipeline, which is characteristic of orbital conditions. The goal of his work is to calculate the startup delay of a “green”-propellant thruster caused by the propellant valve being at a distance from the propellant nozzles in the reaction chamber under conditions of a vacuumized pipeline. The paper considers thermophysical processes during the filling of a vacuumized pipeline between the valve outlet and the propellant nozzle and presents a mathematical model that accounts for propellant ebullition and propellant vapor extrusion through the propellant nozzle until the liquid propellant boundary reaches the reaction chamber inlet. The paper presents the liquid propellant flow rate, the vapor pressure, the temperature, and the relative volumes of the liquid and the vapor calculated as a function of time at different values of the propellant tank pressure and the pipeline-to-nozzle diameter ratio for a thruster of nominal thrust 1 N. It is shown that the effect of the propellant tank pressure and the design parameters of the system of “green” propellant feed to the thruster reaction chamber manifests itself as the thruster startup delay varying in the range from some thousandths to some hundredths of a second, which is comparable with the thruster startup time in the pulsed operation. REFERENCES 1. Belyaev N. M., Belik N.P., Uvarov E. I. Jet Control Systems of Spacecraft. Moscow: Mashinostroyeniye, 1979. 232 pp. (In Rusian). 2. Knyshenko Yu. V. Dynamics of electrically controlled propellant valves for "green"-propellant thrusters. Teh. Meh. 2024. No. 3. Pp. 49-66. (In Ukrainian). https://doi.org/10.15407/itm2024.03.049 3. Rocket Engines - ECAPS : https://www.ecaps.se (Last accessed on July 20, 2025). 4. Timoshenko V. I. Gas-Dynamics of High-Temperature Industrial Processes. Dnipropetrovsk: Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the National Space Agency of Ukraine, 2003. 460 pp. (In Russian). 5. Anflo K,. Thormahlen P., Persson M. Hot-firing tests using a low temperature derivative of LMP-103S. 5th European Conference for Aeronautics and Space Sciences (EUCASS), Germany, 1 - 5 July 2013. www.eucass.eu/2013. 6. Decker M. M., Klein N., Freedman E. et al.. HAN-Based Liquid Gun Propellants: Physical Properties. BRL-TR-2864, 1987. 64 pp. 7. Yoon W., Khandu V. B., Hosung Y. Reactor structure for the decomposition of ADN-based monopropellant. Aerospace. 2023. V. 10. No. 6. 686. https://doi.org/10.3390/aerospace10080686 8. Yoon W., Khandu V. B., Hosung Y. Performance evaluation of ammonium dinitramide-based monopropellant in a 1 N thruster. Aerospace. 2024. V. 11. No. 2. 110. https://doi.org/10.3390/aerospace11020110 9. Timoshenko V. I., Knyshenko Yu. V., Durachenko V. M. Mathematical model of "green"-propellant jet thrusters and its verification. Teh. Meh. 2025. No. 2. Pp. 17-34. (In Ukrainian). https://doi.org/10.15407/itm2025.02.017
ASSESSMENT OF THE PARAMETER VARIATION OF AN ELECTRODYNAMIC SPACE TETHER SYSTEM UNDER THERMAL ACTION
DOI: https://doi.org/10.15407/itm2025.03.031 This paper presents a refined model for determining the tether temperature variation in orbital motion, which is of importance to the operation of passive electrodynamic space tether systems (EDSTSs) with a thermoelectronic coating. It is shown that a thermoelectronic coating of a tether significantly increases the collection of currents by the system, thus considerably increasing the EDSTS operational efficiency in comparison with the absence of additional contactors. The effect of thermal conditions on the EDSTS parameters is studied. The EDSTS component temperature variation is studied using a thermal balance equation, which accounts for the direct solar heat flux, the Earth-reflected solar heat flux, the Earth’s intrinsic heat flux, the aerodynamic heating, the ohmic heating, the electron impact heating, the thermal radiation of the tether, and the tether hat conductivity. To calculate the electric currents in the EDSTS passive operation, use is made of models based on orbitally limited current models for the anode segment of the tether and the Richardson – Dushman theory for total emission from the cathode segment of the tether. It is shown that on of important issues in EDCTS designing and making is the choice of a tether material that would meet certain requirements for its characteristics. The material parameters to be accounted for are the heat capacity, the IR solar absorptance, and the IR emittance. These parameters are crucial in the calculation of the system temperature variation. The greater the heat capacity, the slower the processes of system component heating and cooling. It is shown that the extreme temperatures of the system components in the shadowed and the illuminated portion of the orbit depend significantly of the ratio of the tether IR solar absorptance to the tether IR emittance. This ratio is governed both by a specific material and by the presence of impurities therein and the roughness or mirror finish degree of its surface. REFERENCES 1. Sánchez-Arriaga G., Naghdi S., Wätzig K., Schilm J., Lorenzini E.C. , Tajmar M., Urgoiti E., Tarabini Castellani L., Plaza J.F. , Post J.F. The E.T.PACK project: Towards a fully passive and consumable-less deorbit kit based on low-work-function tether technology. Acta Astronautica. 2020. V. 177. Pp. 821 - 827. https://doi.org/10.1016/j.actaastro.2020.03.036 2. Sánchez-Arriaga G., Sanmartin J. R. Electrical model and optimal design scheme for low work-function tethers in thrust mode. Aerospace Science and Technology. 2020. V. 96. Paper 105519. https://doi.org/10.1016/j.ast.2019.105519 3. Sanchez-Arriaga G., Chen Х. Modeling and performance of electrodynamic low-work-function tethers with photoemission effects. Propulsion and Power. 2018. V. 34. No. 1. Pp. 213 - 220. https://doi.org/10.2514/1.B36561 4. Jensen K. L., Feldman W. D., Moody N. A., O'Shea P. G. A Photoemission model for low work function coated metal surfaces and its experimental validation. Applied Physics. 2016. V. 99. No. 12. Paper 124905. https://doi.org/10.1063/1.2203720 5. Mishchenko O. V. Methodological Support of Electrodynamic Space Tether System Design. PhD thesis. Approved on June 26, 2021. Dnipro, 2021. 226 pp. (In Ukrainian). 6. Williams P., Yeo Sh., Blanksby Ch. Heating and modeling effects in tethered aerocapture missions. Journal of Guidance, Control, and Dynamics. 2003. V. 49. No. 4. Pp. 643 - 654. https://doi.org/10.2514/2.5093 7. Davies J. H., Davies D. R. Earth's surface heat flux. Solid Earth. 2010. V. 1. No. 1. Pp. 5 - 24. https://doi.org/10.5194/se-1-5-2010 8. Williams J. D. Sanmartin J. R., Rand L. P. Low work-function coating for an entirely propellantless bare electrodynamic tether. IEEE Transactions on Plasma Science. 2012. V. 40. No. 5. Pp. 1441 - 1445. https://doi.org/10.1109/TPS.2012.2189589