Science-Based Procedure for Designing Tubular Porous Cooling Systems for Thermal Power Plant Equipment Components

Authors: Genbach A.A., Bondartsev D.Yu. Published: 22.07.2019
Published in issue: #3(126)/2019  

DOI: 10.18698/0236-3941-2019-3-89-106

Category: Power Engineering | Chapter: Machines and Devices, Processes of Refrigeration and Cryogenic Engineering, Air Conditioning  
Keywords: departure from nucleate boiling, tubular porous system, thermal power plants, steam bubble, capillary and bulk forces, heat transfer control, tubular porous coatings, natural mineral media

We investigated critical heat flux phenomena in metallic and porous structures characterised by low thermal conductivity. These structures are used to cool various thermal power plant equipment; their operation involves both gravity and capillary forces. The paper describes the failure mechanism in metallic steam generator surfaces and poorly thermally conductive low-porosity coatings made of natural mineral media (such as granite). We determined how heat flows depend on their duration and penetration depth of thermal disturbance. Tubular porous systems are less bulky and feature high intensity, higher thermal conductivity and reliability. We show that for granite coatings the maximum thickness of the particles detached due to compression forces is (0.25...0.3)·10--2 m. The compression curve sections that govern detachment of particles larger than 0.3·10--2 m are shadowed by the melt curve for high heat flows and short exposure times and by the tension curve in the case of low heat flows and short periods of time. The investigation should help us to design porous coatings usable in cooling systems


[1] Polyaev V.M., Genbach A.N., Genbach A.A. Methods of monitoring energy processes. Exp. Therm. Fluid Sci., 1995, vol. 10, no. 3, pp. 273--286. DOI: 10.1016/0894-1777(94)00061-C

[2] Polyaev V.M., Genbach A.A. Heat transfer in a porous system in the presence of both capillary and gravity forces. Thermal Engineering, 1993, vol. 40, no. 7, pp. 551--554.

[3] Polyaev V.M., Genbach A.N., Genbach A.A. Limiting state of a surface during thermal activity. High Temp., 1991, vol. 29, no. 5, pp. 729--739.

[4] Polyaev V.M., Genbach A.A. Control of heat transfer in a porous cooling system. Proc. 2nd World Conf. Experimental Heat Transfer, Fluid Mechanics and Thermodynamics. Dubrovnik, Yugoslavia, 1991, pp. 639--644.

[5] Polyaev V.M., Genbach A.A., Minashkin D.V. Processes in the porous elliptic heat exchanger. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [Proceedings of Higher Educational Institutions. Маchine Building], 1991, no. 4-6, pp. 73--77 (in Russ.).

[6] Genbach A.A., Bakytzhanov I.B. Protecting TPP bases from earthquakes with the help of porous geo screens. Poisk, 2012, no. 1, pp. 289--297 (in Russ.).

[7] Genbach A.A., Danil’chenko I. Porous desuperheater steam boilers. Promyshlennost’ Kazakhstana [Industry of Kazakhstan], 2012, no. 1, pp. 72--75 (in Russ.).

[8] Genbach A.A., Olzhabaeva K.S. Visualization of thermal effect on porous material in thermal energy installations of ES power plants. Vestnik Natsional’noy inzhenernoy akademii RK [Bulletin of the National Engineering Academy of the Republic of Kazakhstan], 2012, no. 3, pp. 63--67 (in Russ.).

[9] Genbach A.A., Islamov F.A. Research of the nozzle fillets in electrical installations. Vestnik KazNTU, 2013, no. 3, pp. 245--248 (in Russ.).

[10] Genbach A.A., Islamov F.A. Modeling process of turbine rotor hardening. Vestnik KazNTU, 2013, no. 6, pp. 235--240 (in Russ.).

[11] Polyaev V.M., Genbach A.A. Control on heat transfer in porous structures. Izvestiya RAN. Energetika i transport, 1992, vol. 38, no. 6, pp. 105--110 (in Russ.).

[12] Jamialahmadi M., Muller-Steinhagen H., Abdollahi A., et al. Experimental and theoretical studies on subcooled flow boiling of pure liquids and multicomponent mixtures. Int. J. Heat Mass Transf., 2008, vol. 51, no. 9-10, pp. 2482--2493. DOI: 10.1016/j.ijheatmasstransfer.2007.07.052

[13] Ose Y., Kunugi T. Numerical study on subcooled pool boiling. Progr. Nucl. Sci. Tech., 2011, no. 2, pp. 125--129.

[14] Krepper E., Koncar B., Egorov Y. CFD modeling subcooled boiling --- concept, validation and application to fuel assembly design. Nucl. Eng. Des., 2007, vol. 237, no. 7, pp. 716--731. DOI: 10.1016/j.nucengdes.2006.10.023

[15] Ovsyannik A.V. Modelirovanie protsessov teploobmena pri kipenii zhidkostey [Modelling of processes of heat exchange at boiling liquids]. Gomel’, Sukhoi State Technical University of Gomel Publ., 2012.

[16] Alekseik O.S., Kravets V.Yu. Physical model of boiling on porous structure in the limited space. EEJET, 2013, vol. 4, no. 8, pp. 26--31.

[17] Polyaev V.M., Genbach A.A. Analysis of friction and heat exchange laws in porous structure. Vestn. Mosk. Gos. Tekh. Univ. im. N.E. Baumana, Mashinostr. [Herald of the Bauman Moscow State Tech. Univ., Mechan. Eng.], 1991, no. 4, pp. 86--96 (in Russ.).

[18] Polyaev V.M., Genbach A.A., Bocharova I.N. Vliyanie davleniya na intensivnost’ teploobmena v poristoy sisteme. Izvestiya vysshikh uchebnykh zavedeniy. Mashinostroenie [Proceedings of Higher Educational Institutions. Маchine Building], 1992, no. 4--6, pp. 68--72 (in Russ.).

[19] Polyaev V.M., Genbach A.A. Application field of porous system. Izvestiya vysshikh uchebnykh zavedeniy. Energetika, 1991, no. 12, pp. 97--101 (in Russ.).

[20] Genbach A.A., Jamankylova N.O., Bakic Vukman V. The processes of vaporization in the porous structures working with the excess of liquid. Thermal Science, 2017, vol. 21, no. 1A, pp. 363--373. DOI: 10.2298/TSCI160326313G

[21] Genbach A.A., Olzhabayeva K.S., Iliev I.K. Boiling process in oil coolers on porous elements. Thermal Science, 2016, vol. 20, no. 5, pp. 1777--1789. DOI: 10.2298/TSCI150602166G