EXPERIMENTAL DETERMINATION OF CONVECTIVE HEAT TRANSFER COEFFICIENTS IN THERMAL BUOYACY VENTILATION SYSTEM
https://doi.org/10.21822/2073-6185-2018-45-4-133-141
Abstract
Objectives. The main goal of the article is to present the developed method for the experimental determination of convective heat transfer coefficients, suitable for studying the internal convection of models of complex configuration. Method. The study of free convection under the conditions of an internal problem was carried out by determining the conditional thickness of the boundary layer by a graphic method. The first was the selection of the calculated sections and planes for the experimental installation. The selection is carried out in such a way that the calculated planes are perpendicular to the heated walls of the channel in question. Installation of an experimental model is possible only in a room with low internal air mobility, as well as a stable temperature. In this room there should not be heating and heating devices that can create strong convective currents near the channel of the experimental installation. Result. The article presents the results of an experimental study to determine the temperature distribution of the air flow and average convective heat transfer coefficients over the height of the ventilation channel. A decrease in convective heat transfer coefficients at an altitude of 0.5 to 1 meter occurs less noticeably than at an altitude of 1 to 2 meters, which is associated with the restoration of flow after a vent removal. At the stabilization section, there is first a gradual decrease, and then an increase in axial velocity, which is caused by the merging of multidirectional air flows in this area. Conclusion. It was revealed that in the case of modeling free convection under the conditions of an internal problem in the presence of heat-removing boundaries within the limits of the calculated temperature difference, taking into account the flow turbulization has practically no effect on the final results.
About the Authors
D. V. Abramkina
Moscow State University of Civil Engineering (National Research University)
Russian Federation
Russian Federation
Teacher, Department "Heat and gas supply and ventilation"
26 Yaroslavskoye Shosse, Moscow 129337, Russia
A. A. Abramyan
Moscow State University of Civil Engineering (National Research University)
Russian Federation
Russian Federation
Bachelor, Department "Heat and gas supply and ventilation"
26 Yaroslavskoye Shosse, Moscow 129337, Russia
E. R. Shevchenko-Enns
Moscow State University of Civil Engineering (National Research University)
Russian Federation
Russian Federation
Bachelor, Department "Heat and gas supply and ventilation"
26 Yaroslavskoye Shosse, Moscow 129337, Russia
References
1. Tongbai P. Enhancement of roof solar chimney performance for building ventilation / P. Tongbai, T. Chitsomboon // Journal of power and energy engineering – 2014. - №2. – Pp. 22-29.
2. Korepanov E.V. Svobodnaya konvektsiya v oknakh s dvoinym ostekleniem / E.V. Korepanov // Izvestiya vysshikh uchebnykh zavedenii. Stroitel'stvo – 2005 – №2 – S. 106-113.[ Korepanov E.V. Free convection in double glazed windows / E.V. Korepanov // Proceedings of higher educational institutions. Construction - 2005 - №2 - P. 106-113. (in Russ.)]
3. Holman J.P. Experimental methods for engineers / J.P. Holman – NY.: McGraw-Hill series in mechanical engineering, 2012. – 761 p.
4. Korepanov E.V. Konvektivnye techeniya i teploobmen v vozdushnykh polostyakh stroitel'nykh izdelii / E.V. Korepanov // Intellektual'nye sistemy v proizvodstve. -2014. – № 2 (24). – S. 184-188. [Korepanov E.V. Convective flows and heat transfer in the air cavities of building products / E.V. Korepanov // Intellectual systems in production. -2014. - № 2 (24). - p. 184-188. (in Russ.)]
5. Danin V.V. Eksperimental'noe izuchenie svobodno – konvektivnogo okhlazhdeniya teplonagruzhennykh poverkhnostei / V.V. Danin, O.B. Tsvetkov, O.P. Krektunov, S.E. Semashko // Nauchnyi zhurnal NIU ITMO. Seriya: Protsessy i apparaty pishchevykh proizvodstv. – 2014. – № 2. – C. 7-15.[ Danin V.V. Experimental study of free - convective cooling of heat-loaded surfaces / V.V. Danin, OB Tsvetkov, O.P. Krektunov, S.E. Semashko // Scientific journal NRU ITMO. Series: Processes and equipment for food production. - 2014. - № 2. - C. 7-15. 9 (In Russ.)]
6. Zyuzgin A.B. Convective motions in near-critical fluids under real zero-gravity conditions / A.B. Zyuzgin, A.I. Ivanov, V.I. Polezhaev, G.F. Putin, E. B. Soboleva // Cosmic Investigations – 2001 – V.39. №2 – Pp. 188-200.
7. Ekkert E. R., Dreik R. M. Teoriya teplo- i massoobmena. / E.R. Ekkert, R.M. Dreik - M.—L.: Gosenergoizdat, 1961. – 680 s.[ Eckert, E. R., Drake, R. M. The Theory of Heat and Mass Transfer. / E.P. Eckert, R.M. Drake - M. — L .: Gosenergoizdat, 1961. - 680 p (In Russ.)]
8. Mindubaev M.G., Demezhko D.Yu. Svobodnaya teplovaya konvektsiya v burovykh skvazhinakh: chislennoe modelirovanie i eksperimental'nye dannye / M.G. Mindubaev, D.Yu. Demezhko // Monitoring. Nauka i tekhnologii – 2012 – №4. – S. 12-18. http://csmos.ru/download/mnt/mnt_v013_art02.rar [Mindubaev MG, Demezhko D.Yu. Free thermal convection in boreholes: numerical modeling and experimental data / MG. Mindubaev, D.Yu. Demezhko // Monitoring. Science and Technology - 2012 - №4. - p. 12-18. http://csmos.ru/download/mnt/mnt_v013_art02.rar (in Russ.)]
9. Rikhter G. Gidravlika truboprovodov: Osnovnye polozheniya, rezul'taty issledovanii, praktich. raschety i izgotovlenie truboprovodov / G.Rikhter – M.-L.: Onti. Glav. red. energetich. lit-ry, 1936. – 324 s.[ G. Richter. Hydraulics of pipelines: Basic provisions, results of research, practical. calculations and production of pipelines / G.Rikhter - M.L.: Onti. Chapters. ed. energetic liters, 1936. – 324 (In Russ.)]
10. Groenhout N.K., Morrison L. G., Behnia M. Natural convection heat transfer in a solar collector with complex geometry. / N.K. Groenhout, L.G. Morrison, M. Behnia // Conference: 39th National Heat Transfer Symposium of Japan, Sapporo. – 2002. – Pp. 317-318. https://www.researchgate.net/publication/267780417
11. Dement'ev M.A. O dvizhenii zhidkosti v mestakh povorota rusla. / M.A. Dement'ev – L.: Izd. sektora gidrotekhniki i gidrotekhn. sooruzhenii, 1930. – 107 s.[ Dementiev M.A. On the movement of fluid in places of rotation of the channel. / M.A. Dementiev - L .: Izd. sector of hydraulic engineering and hydraulic engineering. constructions, 1930. - 107 p. (In Russ.)]
12. Mashenkov A.N., Kosolapov E.A. O metodakh chislennogo resheniya dvumernykh uravnenii Bussineska dlya svobodnoi konvektsii / A.N. Mashenkov, E.A. Kosolapov // Stroitel'nye nauki – 2010. – №3. – S. 292-296. https://cyberleninka.ru/article/v/o-metodah-chislennogo-resheniya-dvumernyh-uravneniy-bussineska-dlyasvobodnoy-konvektsii[Mashenkov A.N., Kosolapov E.A. On methods for the numerical solution of the twodimensional Boussinesq equations for free convection / A.N. Mashenkov, E.A. Kosolapov // Building Sciences - 2010. - №3. - p. 292-296. https://cyberleninka.ru/article/v/o-metodah-chislennogo-resheniya-dvumernyhuravneniy-bussineska-dlya-svobodnoy-konvektsii (In Russ.)]
13. Taylor A. Oetelaar1. Determination of the convective heat transfer coefficient of hot air rising through terracotta flues / aylor A. Oetelaar1, Clifton R. Johnston // Transactions of the Canadian Society for Mechanical Engineering – 2012. – V. 36. - № 4. – Pp. 413-427.
14. De Giorgi L., Bertola V., Cafaro E. Thermal convection in double glazed windows with structured gap. / L. De Giorgi, V. Bertola, E. Cafaro // Energy and Buildings – 2011. – Vol. 43. – Iss. 8. – Pp. 2034-2038. https://doi.org/10.1016/j.enbuild.2011.03.043
15. Bogoslovskii V.N. Stroitel'naya teplofizika. Teplofizicheskie osnovy otopleniya, ventilyatsii i konditsionirovaniya vozdukha / V.N. Bogoslovskii – M.: Izd. Vysshaya shkola, 1982. – 415 s.[Bogoslovskii V.N. Construction thermophysics. Thermophysical foundations of heating, ventilation and air conditioning / V.N. Bogoslovskii - M .: Izd. Higher school, 1982. - 415 p. (In Russ.)]
16. Arıcı M., Yılmaz B., Karabay H. Investigation of heat insulation performance of hollow clay bricks filled with perlite. / M. Arıcı, B. Yılmaz, H. Karabay // Special issue of the 2nd International Conference on Computational and Experimental Science and Engineering (ICCESEN 2015). – 2016. – Vol. 130. – No. 1. – Pp. 266 - 268. http://przyrbwn.icm.edu.pl/APP/PDF/130/a130z1p069.pdf
17. Popov I.A. Gidrodinamika i teploobmen vneshnikh i vnutrennikh svobodnokonvektivnykh vertikal'nykh techenii s intensifikatsiei. Intensifikatsiya teploobmena: monografiya / Pod. obshch. red. Yu.F. Gortyshova – Kazan': Tsentr innovatsionnykh tekhnologii, 2007. – 326 s.[ Popov I.A. Hydrodynamics and heat transfer of external and internal free convective vertical flows with intensification. Intensification of heat transfer: monograph / Under. total ed. Yu.F. Gortyshova - Kazan: Center for Innovative Technologies, 2007. - 326 p. (In Russ.)]
18. Parra J., Guardo A., Egusquiza E., Alavedra P. Thermal performance of ventilated double skin façades with venetian blinds. / J. Parra, A. Guardo, E. Egusquiza, P. Alavedra // Energies. – 2015. – No. 8. – Pp. 4882-4898. doi: 10.3390/en8064882
19. Tongbai P. Enhancement of roof solar chimney performance for building ventilation / P. Tongbai, T. Chitsomboon // Journal of power and energy engineering – 2014. - №2. – Pp. 22-29.
20. Holman J.P. Experimental methods for engineers / J.P. Holman – NY.: McGraw-Hill series in mechanical engineering, 2012. – 761 p.
21. Danin V.V. Eksperimental'noe izuchenie svobodno – konvektivnogo okhlazhdeniya teplonagruzhennykh poverkhnostei / V.V. Danin, O.B. Tsvetkov, O.P. Krektunov, S.E. Semashko // Nauchnyi zhurnal NIU ITMO. Seriya: Protsessy i apparaty pishchevykh proizvodstv. – 2014. – № 2. – C. 7-15.[ Danin V.V. Experimental study of free - convective cooling of heat-loaded surfaces / V.V. Danin, OB Tsvetkov, O.P. Krektunov, S.E. Semashko // Scientific journal NRU ITMO. Series: Processes and equipment for food production. - 2014. - № 2. - C. 7-15. 9 (In Russ.)]
22. Ekkert E. R., Dreik R. M. Teoriya teplo- i massoobmena. / E.R. Ekkert, R.M. Dreik - M.—L.: Gosenergoizdat, 1961. – 680 s.[ Eckert, E. R., Drake, R. M. The Theory of Heat and Mass Transfer. / E.P. Eckert, R.M. Drake - M. — L .: Gosenergoizdat, 1961. - 680 p (In Russ.)]
23. Rikhter G. Gidravlika truboprovodov: Osnovnye polozheniya, rezul'taty issledovanii, praktich. raschety i izgotovlenie truboprovodov / G.Rikhter – M.-L.: Onti. Glav. red. energetich. lit-ry, 1936. – 324 s.[ G. Richter. Hydraulics of pipelines: Basic provisions, results of research, practical. calculations and production of pipelines / G.Rikhter - M.L.: Onti. Chapters. ed. energetic liters, 1936. – 324 (In Russ.)]
24. Dement'ev M.A. O dvizhenii zhidkosti v mestakh povorota rusla. / M.A. Dement'ev – L.: Izd. sektora gidrotekhniki i gidrotekhn. sooruzhenii, 1930. – 107 s.[ Dementiev M.A. On the movement of fluid in places of rotation of the channel. / M.A. Dementiev - L .: Izd. sector of hydraulic engineering and hydraulic engineering. constructions, 1930. - 107 p. (In Russ.)]
25. Taylor A. Oetelaar1. Determination of the convective heat transfer coefficient of hot air rising through terracotta flues / aylor A. Oetelaar1, Clifton R. Johnston // Transactions of the Canadian Society for Mechanical Engineering – 2012. – V. 36. - № 4. – Pp. 413-427.
26. Bogoslovskii V.N. Stroitel'naya teplofizika. Teplofizicheskie osnovy otopleniya, ventilyatsii i konditsionirovaniya vozdukha / V.N. Bogoslovskii – M.: Izd. Vysshaya shkola, 1982. – 415 s.[Bogoslovskii V.N. Construction thermophysics. Thermophysical foundations of heating, ventilation and air conditioning / V.N. Bogoslovskii - M .: Izd. Higher school, 1982. - 415 p. (In Russ.)]
27. Popov I.A. Gidrodinamika i teploobmen vneshnikh i vnutrennikh svobodnokonvektivnykh vertikal'nykh techenii s intensifikatsiei. Intensifikatsiya teploobmena: monografiya / Pod. obshch. red. Yu.F. Gortyshova – Kazan': Tsentr innovatsionnykh tekhnologii, 2007. – 326 s.[ Popov I.A. Hydrodynamics and heat transfer of external and internal free convective vertical flows with intensification. Intensification of heat transfer: monograph / Under. total ed. Yu.F. Gortyshova - Kazan: Center for Innovative Technologies, 2007. - 326 p. (In Russ.)]
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For citations:
Abramkina D.V., Abramyan A.A., Shevchenko-Enns E.R. EXPERIMENTAL DETERMINATION OF CONVECTIVE HEAT TRANSFER COEFFICIENTS IN THERMAL BUOYACY VENTILATION SYSTEM. Herald of Dagestan State Technical University. Technical Sciences. 2018;45(4):133-141. (In Russ.) https://doi.org/10.21822/2073-6185-2018-45-4-133-141
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