Technique of studying thermal diffusivity of metallics in different directions in a field of centrifugal accelerations and forces
Tóm tắt
Study of the thermal diffusivity of metallics in a field of centrifugal accelerations and forces is essential for aerospace engineering. Characteristics of thermal diffusivity of materials are used in calculations of thermal state of blades and disks of turbine rotors. An original technique and a device on semiconductors have been developed for determination of thermophysical characteristics of materials on an acceleration bench using a vacuum chamber, under centrifugal forces and accelerations. Presented are results on nonstationary heating of heat conductors in the radial and circumferential directions in a field of centrifugal forces and accelerations. Analysis of experimental results shows that the thermal diffusivity of heat conductors grows with rotational speed as compared with a static state without rotation. The thermal diffusivity phenomenon of concern has two components: from centrifugal acceleration and from centrifugal tensile load. From experimental data on the effect of tensile forces it follows that the second component is small. Thus, said thermal diffusivity growth is strongly associated with increase in the velocity of electron drift in ametal under centrifugal acceleration forces.
Tài liệu tham khảo
Gori, P. et al., Accuracy of Lumped-Parameter Representations for Heat Conduction Modeling in Multilayer Slabs, J. Phys. Conf. Ser., 2015, vol. 655, p. 012065.
Jiang, L., Wang, L., Wang, R., and Dai, Y., Influence of Variable Thermal Conductivity and Permeability of Adsorbents on Simulation: A Case Study of a Two-Stage Freezing System, Heat Transfer Res., 2015, vol. 46, no. 2, pp. 141–157.
Karthik, R., Nagarajan, R.H., Praveen, K.S., and Raja, B., Experimental Investigation on Thermal Conductivity Enhancement of Copper (II) Oxide–DIWater Nanofluids, J. Eng. Therm., 2014, vol. 23, no. 4, p. 341.
Filippov, A.I., Akhmetova, O.V., Zelenova, M.A., and Asylbaev, M.A., Temperature Field in Inhomogeneous Strongly AnisotropicMedium with Sources, J. Eng. Therm., 2014, vol. 23, no. 2, p. 158.
Gregorova, E. et al., Porous Alumina and Zirconia Ceramics with Tailored Thermal Conductivity, J. Phys. Conf. Ser., 2012, vol. 395, p. 12022.
Minea, A.A., Numerical Simulation and Experimental Validation ofHeat Transfer Enhancement on a Loaded Heat Treatment Furnace, J. Eng. Therm., 2010, vol. 19, no. 3, p. 158.
Alekseev, V.P. and Karaban, V.M., Simulation of Nonstationary Temperature Fields of a Thermostable Substrate for a Proportional Temperature Regulator, J. Eng. Therm., 2008, vol. 17, no. 3, p. 253.
Lepeshkin, A.R., Study of Thermal Diffusivity of Metals Taking into Account the Electron Inertia under Centrifugal Acceleration, Proc. Conf. on Actual Problems of Physics, Moscow: FIAN, 2012, pp. 65/66.
Lepeshkin, A.R. and Bychkov, N.G., The Method and Apparatus for Determination of Thermophysical Characteristics of Solids in a Field of Centrifugal Forces, RFPatent 2235982, publ. 20.04.2011, byull. no. 11.
Emirov, S.N., Bulaeva, N.M., and Ramazanova, E.N., The Effect of Pressure and Temperature on Thermal Conductivity of Mono- and Polycrystal Samples of Gallium Antimonide, Proc. XII Russ. Conf. on Thermophysical Properties of Substances, Moscow, 2008, p. 306.
Tolman, R.C. and Stewart, T.D., Phys. Rev., 1916, no. 8, p. 164.
Ginzburg, V.L. and Kogan, Sh.M., On Electron Inertia Experiments, JETP, 1977, vol. 61, no. 3(9), pp. 1177–1180.
Landau, L.D. and Lifshitz, E.M., Teoreticheskaya fizika, tom VIII, Elektrodinamika sploshnykh sred, 4- e izd. (Theoretical Physics, vol. VIII, Electrodynamics of Continuous Media), 4th ed., Moscow: Fizmatlit, 2005.
Sivukhin, D.V., Obshchii kurs fiziki, tom3, Elektrichestvo, 5-e izd. (The General Course of Physics, vol. 3, Electricity), 5th ed., Moscow: Fizmatlit, 2009.
Troitskii, O.A. and Stashenko, V.I., Stewart–Tolman Effect at High-Speed Wire Drawing and in Collision of a Bullet with a Target, Izv. Akad. Electr. Eng., 2011, no. 1, pp. 37–43.
Lepeshkin, A.R. and Bychkov N.G., Thermal Diffusivity of Materials in a Field of Centrifugal Forces and Accelerations, Proc. Fifth Russ. Nat. Conf. on Heat Transfer (October 25–29, 2010, Moscow), vol. 1, General Problem Reports, Moscow:MEI, 2010, pp. 131–133.
Bol’shaya sovetskaya entsiklopediya (Great Soviet Encyclopedia), Moscow: Sovetskaya Encyclopedia, 1975.
Pavlov, P.A. and Khokhlov, A.F., Fizika tverdogo tela (Solid State Physics), 4th ed., Moscow: LENAND, 2015.