Transient Processes at Thermosyphons
DOI:
https://doi.org/10.14529/power170401Keywords:
thermosiphon, temperature, thermal resistance, flue gases pipe, time constantAbstract
The work is aimed at studying of transient processes in thermosyphons. The calculated dependences for determining the basic temperature characteristics of the controlled object are obtained. For this purpose, the thermal resistances of main elements in a thermosyphon have been wrote and calculated. The equations for calculating the change in saturation temperature in a thermosyphon are proposed. These changing strongly depends on the design and operating parameters of the heat exchanger. In this case a thermosyphon is considered as an object of regulation. Gases flow rate changing (or heat exchanger switch off) is considered as an inlet distribution. The time constant expressions and the gain factor with a stepwise increase in the temperature of the gases are obtained. The calculations of the change in the saturation temperature in a thermosyphon with a linear decrease in the temperature of gases are shown. The data of experimental studies are given when the heat exchanger is stopped. For these investigations the changes in the temperature of gases and the saturation temperature in thermosyphons were held. A conducted comparison of the calculated and experimental data shows a good agreement.
References
Vasil'ev L.L., Papchenkov A.I., Grakovich L.P., Vasil'ev L.L. Jr. [Thermosyphons and Their Use in Engineering]. Teplovye protsessy v tekhnike [Thermal Processes in Engineering], 2015, vol. 7, no. 1, pp. 11–23.
(in Russ.)
Moy Kai, Wei Baoming, Zhang Zhongxing. Study in Prolonging the Life Time of Carbon Steel-Water Heat Pipe. Proceedings of the International Heat Pipe Forum, Minsk, 1990.
Bricard A. Ricent Advances in Heat Pipes for Heat Exchangers. Proceedings of the International Heat Pipe Forum, Minsk, 1990.
Vasil'ev L.L., S.V. Konev. Heat Transfer Tubes. Nauka i tekhnika [Science and Technology], Minsk, 1972, pp. 129–130. (in Russ.)
Grakovich L.P., Rabetsky M.I., Vasiliev L.L., Vasiliev L.L. Jr., Bogdanovich S.P., Pesetskii S.S. Poly-mer Flat Loop Thermosyphons. 11th International Heat Pipe Symposium (11 IHPS), 2013, June 9th – 12th, Beijing
(China).
Vasiliev L.L., Vasiliev L.L. Jr. Horizontal Vapordynamic Thermosyphons, Fundamentals and Practical Applications. 16th International Heat Pipes Conference (16th IHPC), Lyon, France, May 20–24, 2012.
Vasiliev L.L., Morgun V.A. Rabetsky M.I. Patent US, no. 4554966, 26.11.1985.
Vasiliev L.L., Zhuravlyov A.S., Shapovalov A.V. Heat Transfer in Mini Channels with Micro/Nano Particles Deposited on a Heat-Loaded Wall. Journal of Enhanced Heat Transfer, 2012, vol. 19, no. 1, рp. 13–24.
DOI: 10.1615/JEnhHeatTransf.2011003350
Xuebin Wang, Amir Pakdel, Jun Zhang, Qunhong Weng, Tianyou Zhai, Chunyi Zhi, Dmitri Golberg,
Yoshio Bando, Large-Surface-Area BN Nanosheets and Their Utilization in Polymeric Composites with Im-proved Thermal and Dielectric Properties, Nanoscale Research Letters, 2012, 7:662. DOI: 10.1186/1556-276X-7-662
Munts V.A., Papchenkov A.I. [Modeling of the Process of Condensation of Water Vapor from the Vapor-gas Mixture in the Thermosyphon Cavity]. Energetik, 2014, no. 8, pp. 45–47. (in Russ.)
Munts V.A., Papchenkov A.I. [The Results of an Industrial Experiment to Measure the Operating Pa-rameters of Thermosyphons of a Recovery Boiler]. Promyshlennaya teplotekhnika [Industrial Heat Engineer-ing], 2014, vol. 36, no. 3, pp. 83–87. (in Russ.)
Munts V.A., Papchenkov A.I. [Ultimate Heat Transfer Capacities of Thermosyphons of Heat Recov-ery Units of Non-ferrous Metallurgy Furnaces]. XXXIII Vserossiyskaya konferentsiya po problemam nauki i tekhnologiy [XXXIII All-Russian Conference on Problems of Science and Technology], 2013.
Munts V.A., Papchenkov A.I., Papchenkov I.N. Ustroystvo dlya izmereniya temperatury [Tempera-ture Measuring Device]. Patent RF, no. 127458, 2013.
Bezrodnyy M.K., Alekseenko D.V. [The Intensity of Heat Exchange in the bBoiling Region of Evap-orative Thermosyphons]. Teploenergetika [Heat Power Engineering], 1977, no. 7, pp. 83–85. (in Russ.)
Bezrodnyy M.K. Krizisy teploperenosa v zamknutykh dvukhfaznykh termosifonakh: dis. na soiskanie uchenoy stepeni doktora tekhnicheskikh nauk [Heat Transfer Crises in Closed Biphase Thermosyphons. Doct. sci. diss.]. Kiev, 1983. 109 p.
Il'in V.A. Eksperimental'noe issledovanie teplogidravlicheskikh kharakteristik i ustoychivosti vysoko nagruzhennykh teplovykh trub dlya perspektivnykh sistem avariynogo raskholazhivaniya reaktornykh ustano-vok: dis. na soiskanie uchenoy stepeni kandidata tekhnicheskikh nauk [Experimental Study of Thermal-hydraulic Cha¬racteristics and Stability of High-loaded Heat Pipes for Advanced Systems of Emergency Cool-ing of Reactor Plants. Cand. sci. diss.]. St. Petersburg, 2011. 121 p.
LabuntsovD.A. [On the Effect of Convective Heat Transfer and Inertial Forces on Heat Transfer dur-ing the Laminar Flow of a Condensate Film]. Teploenergetika [Heat Power Engineering], 1956, no. 12, pp. 47–50.
(in Russ.)
Kutateladze S.S. Osnovy teorii teploobmena [Fundamentals of the Theory of Heat Transfer], Novosi-birsk, Nauka Publ., 1970. 660 p.
Mikheev M.A., Mikheeva I.M. Osnovy teploperedachi [Fundamentals of Heat Transfer], Moscow, Energiya Publ., 1977. 344 p.
Isachenko V.P., Osipova V.A., Sukomel А.S. Heat Transfer: Textbook for High Schools. 4th ed., re-vised and enlarged, Moscow, Energoizdat Publ., 1981. 416 p.
Korn G.A., Korn T.M. Spravochnik po matematike dlya nauchnykh rabotnikov i inzhenerov: opre-deleniya, teoremy, formuly [A Handbook of Mathematics for Scientists and Engineers: Definitions, Theorems, Formulas]. 5th ed. Moscow, Nauka Publ., 1984. 832 p.