MATHEMATICAL MODELS OF HEAT TRANSFER IN ELEMENTS OF TURBO GENERATORS (CONTINUED)

2020;
: 21-28
https://doi.org/10.23939/ujit2020.02.021
Received: June 26, 2020
Accepted: October 25, 2020

Цитування за ДСТУ: Гавриш В. І., Білінський Б. О., Король О. С., Шкраб Р. Р., Зімоха І. О. Математичні моделі теплообміну в елементах турбогенераторів (продовження). Український журнал інформаційних технологій. 2020, т. 2, № 1. С. 21–28.

Citation APA: Havrysh, V. I., Bilinskyi, B. O., Korol, O. S., Shkrab, R. R., & Zimoha, I. O. (2020). Mathematical models of heat transfer in elements of turbo generators (continued). Ukrainian Journal of Information Technology, 2(1), 21–28. https://doi.org/10.23939/ujit2020.02.021

1
Lviv Polytechnic National University, Lviv, Ukraine
2
Lviv Polytechnic National University
3
Lviv Polytechnic National University
4
Lviv Polytechnic National University, Lviv, Ukraine
5
Lviv Polytechnic National University

Previously developed [8] and presented new mathematical models for the analysis of temperature regimes in individual elements of turbo generators, which are geometrically described by isotropic half-space and space with an internal heat source of cylindrical shape. Cases are also considered for half-space, when the fuel-releasing cylinder is thin, and for space, when it is heat-sensitive. For this purpose, using the theory of generalized functions, the initial differential equations of thermal conductivity with boundary conditions are written in a convenient form. To solve the obtained boundary value problems of thermal conductivity, the integral Hankel transformation was used, and as a result, analytical solutions in the images were obtained. The inverse Hankel integral transformation was applied to these solutions, which made it possible to obtain the final analytical solutions of the initial problems. The obtained analytical solutions are presented in the form of improper convergent integrals. Computational programs have been developed to determine the numerical values ​​of temperature in the above structures, as well as to analyze the heat transfer in the elements of turbo generators due to different temperature regimes due to heating by internal heat sources concentrated in the cylinder volume. Using these programs, graphs are presented that show the behavior of curves constructed using numerical values ​​of the temperature distribution depending on the spatial radial and axial coordinates. The obtained numerical values ​​of temperature indicate the correspondence of the given mathematical models for determining the temperature distribution to the real physical process. The software also allows you to analyze media with internal heating, concentrated in the spatial figures of the correct geometric shape, in terms of their heat resistance. As a result, it becomes possible to increase it, to determine the allowable temperatures of normal operation of turbo generators, to protect them from overheating, which can cause the destruction of not only individual elements but also the entire structure.

[1]     Ba­yat, A., Mo­osa­vi, H., & Ba­yat, Y. (2015). Ther­mo-mec­ha­ni­cal analysis of functi­onally gra­ded thick sphe­res with li­ne­arly ti­me-de­pen­dent tem­pe­ra­tu­re. Sci­en­tia Ira­ni­ca, 22(5), 1801–1812.

[2]     Car­pin­te­ri, A., & Pag­gi, M. (2008). Ther­mo­elas­tic mis­match in non­ho­mo­ge­ne­ous be­ams. J. Eng. Math, 61, 2–4, 371–384.

[3]     Gavrysh, V. I., & Fe­das­juk, D. V. (2012). Mo­del­ju­vannja tem­pe­ra­turnyh rezhymiv u kus­ko­vo-od­no­ridnyh struk­tu­rah. Lviv: Publishing NU "L'vivs'ka po­li­teh­ni­ka", pp. 176–178.

[4]     Ghan­nad, M., & Yag­ho­obi, M. P. (2015). A ther­mo­elas­ti­city so­lu­ti­on for thick cylin­ders sub­jec­ted to ther­mo-mec­ha­ni­cal lo­ads un­der va­ri­ous bo­un­dary con­di­ti­ons. Int. Jo­ur­nal of Ad­van­ced De­sign & Ma­nu­fac­tu­ring Techno­logy, 8(4), 1–12.

[5]     Har­ma­tiy, G. Yu., Po­po­vich, V. S., & Krul, M. (2019). Influ­en­ce of ther­mal sen­si­ti­vity of ma­te­ri­al on unstab­le ther­mal sta­te of mul­ti­la­yer pla­te. Physi­co-che­mi­cal mec­ha­nics of ma­te­ri­als, 1, 98–104. [In Uk­ra­ini­an].

[6]     Havrysh, V. I., Ba­ra­netskiy, Ya. O., & Kol­ya­sa, L. I. (2018). In­ves­ti­ga­ti­on of tem­pe­ra­tu­re mo­des in ther­mo­sen­si­ti­ve non-uni­form ele­ments of ra­dioelectro­nic de­vi­ces. Ra­dio Electro­nics, Com­pu­ter Sci­en­se, Control, 3(46), 7–15.

[7]     Havrysh, V. I., Kol­ya­sa, L. I., & Uk­han­ka, O. M. (2019). De­ter­mi­na­ti­on of tem­pe­ra­tu­re fi­eld in ther­mally sen­si­ti­ve la­ye­red me­di­um with inclu­si­ons. Nau­kov­yi Visnyk NHU, 1, 94–100.

[8]     Havrysh, V. I., Ko­rol, O. S., Shkrab, R. R., & Zi­mo­ha, I. O. (2019). Mat­he­ma­ti­cal mo­dels of he­at transfer in ele­ments of tur­bo­ge­ne­ra­tors. Uk­ra­ini­an Jo­ur­nal of In­for­ma­ti­on Technology, 1(1), 22–27. https://doi.org/10.23939/ujit2019.01.022

[9]     Hrytsiuk, Yu., & Bilas, O. (2019). Visualization of Software Quality Expert Assessment. IEEE 2019 14th International Scientific and Technical Conference on Computer Sciences and Information Technologies (CSIT 2019), (Vol. 2, pp. 156–160), 17–20 September, 2019. https://doi.org/10.1109/stc-csit.2019.8929778

[10]  Hrytsiuk, Yu., & Grytsyuk, P., Dyak, T., & Hrynyk, H. (2019). Software Development Risk Modeling. IEEE 2019 14th International Scientific and Technical Conference on Computer Sciences and Information Technologies (CSIT 2019), (Vol. 2, pp. 134–137), 17–20 September, 2019. https://doi.org/10.1109/stc-csit.2019.8929778

[11]  Jab­ba­ri, M., Ka­ram­po­ur, S., & Es­la­mi, M. R. (2011). Ra­di­ally symmet­ric ste­ady sta­te ther­mal and mec­ha­ni­cal stres­ses of a po­ro FGM hol­low sphe­re. In­ter­na­ti­onal Scho­larly Re­se­arch Net­work ISRN Mec­ha­ni­cal En­gi­ne­ering, 3, 1–7. https://doi.org/10.5402/2011/305402

[12]  Kol­ya­no, Yu. M. (1992). Met­hods of ther­mal con­duc­ti­vity and ther­mo­elas­ti­city of an in­ho­mo­ge­ne­ous body. Kyiv: Nau­ko­va dum­ka. [In Uk­ra­ini­an].

[13]  Korn, G., & Korn, T. (1977). A gui­de to mat­he­ma­tics for sci­en­tists and en­gi­ne­ers. Mos­cow: Sci­en­ce. [In Rus­si­an].

[14]  Lu­kas­he­vich, A. (2019). Tem­pe­ra­tu­re fi­eld in the con­tact zo­ne du­ring ro­tary fric­ti­on wel­ding of me­tals. Physi­co-che­mi­cal mec­ha­nics of ma­te­ri­als, 1, 41–46. [In Uk­ra­ini­an].

[15]  Mo­haz­zab, A. H., & Jab­ba­ri, M. (2011). Two-Di­men­si­onal Stres­ses in a Hol­low FG Sphe­re with He­at So­ur­ce. Ad­van­ced Ma­te­ri­als Re­se­arch, 264–265, 700–705. https://doi.org/10.4028/scientific.net/amr.264-265.700

[16]  Podstri­gach, Ya. S., Lo­ma­kin, V. A., & Kol­ya­no, Yu. M. (1984). Ther­mo­elas­ti­city of bo­di­es of in­ho­mo­ge­ne­ous struc­tu­re. Mos­cow: Sci­en­ce. [In Rus­si­an].

[17]  Yan­gi­an, Xu., & Da­ih­ui, Tu. (2009). Analysis of ste­ady ther­mal stress in a ZrO2/FGM/Ti-6Al-4V com­po­si­te ECBF pla­te with tem­pe­ra­tu­re-de­pen­dent ma­te­ri­al pro­per­ti­es by NFEM, WA­SE. International Conf. on In­for­ma. Eng., 2–2, 433–436.