As a highly efficient heat transport medium, the study of the melting and heat transfer characteristics of metallic fluids in phase change processes under magnetic fields is of great importance for industrial processes such as fusion reactors, electromagnetic metallurgy, and additive manufacturing. In this paper, the melting process of metallic gallium under a strong magnetic field was studied by building a comprehensive experimental system for heat transfer through phase change of metal, and the heat transfer characteristics of metallic gallium melting under the action of a magnetic field were obtained. The dynamic average distance of the heated wall from the phase interface during melting instead of the fixed characteristic length was used to study the variation of the relative strength of convective heat transfer and thermal conductivity with Fourier number (Fo) during melting. The results show that: under a small Hartmann number (Ha), the melting has a melting-promoting effect at the early stage and is inhibited at the later stage; under a large Hartmann number the magnetic field has an inhibiting effect on the convection during the melting of gallium metal, and the melting process shows a laminar and uniform advance. The magnetic field reduces the height of the dominant zone of thermal conductivity at the bottom of the cavity during the melting process and suppresses temperature fluctuations during the melting process, resulting in a uniform temperature distribution during the melting process.
CAI Zhiyang
,
MENG Xu
,
ZHANG Dengke
,
WU Xi
,
WANG Zenghui
. Experimental study of MHD effect of phase change heat transfer in metals under the influence of a strong magnetic field[J]. Journal of University of Chinese Academy of Sciences, 2024
, 41(6)
: 746
-754
.
DOI: 10.7523/j.ucas.2023.021
[1] Stefan J. Ueber Die Theorie der Eisbildung, insbesondere über Die Eisbildung im Polarmeere[J]. Annalen Der Physik, 1891, 278(2): 269-286. DOI:10.1002/andp.18912780206.
[2] Shokouhmand H, Kamkari B. Experimental investigation on melting heat transfer characteristics of lauric acid in a rectangular thermal storage unit[J]. Experimental Thermal and Fluid Science, 2013, 50: 201-212. DOI:10.1016/j.expthermflusci.2013.06.010.
[3] Al Omari S A B, Ghazal A M, Elnajjar E, et al. Vibration-enhanced direct contact heat exchange using gallium as a solid phase change material[J]. International Communications in Heat and Mass Transfer, 2021, 120: 104990. DOI:10.1016/j.icheatmasstransfer.2020.104990.
[4] 颜晓虹, 胡学功, 赵耀华. 微槽群相变式微冷系统的换热特性实验[J]. 中国科学院研究生院学报, 2006, 23(3): 313-316. DOI:10.7523/j.issn.2095-6134.2006.3.005.
[5] Coenen J W, Philipps V, Brezinsek S, et al. Analysis of tungsten melt-layer motion and splashing under tokamak conditions at TEXTOR[J]. Nuclear Fusion, 2011, 51(8): 083008. DOI:10.1088/0029-5515/51/8/083008.
[6] Jany P, Bejan A. Scaling theory of melting with natural convection in an enclosure[J]. International Journal of Heat and Mass Transfer, 1988, 31(6): 1221-1235. DOI:10.1016/0017-9310(88)90065-8.
[7] Gau C, Viskanta R. Effect of natural convection on solidification from above and melting from below of a pure metal[J]. International Journal of Heat and Mass Transfer, 1985, 28(3): 573-587. DOI:10.1016/0017-9310(85)90180-2.
[8] Gau C, Viskanta R. Melting and solidification of a pure metal on a vertical wall[J]. Journal of Heat Transfer, 1986, 108(1): 174-181. DOI:10.1115/1.3246884.
[9] Kumar L, Manjunath B S, Patel R J, et al. Experimental investigations on melting of lead in a cuboid with constant heat flux boundary condition using thermal neutron radiography[J]. International Journal of Thermal Sciences, 2012, 61: 15-27. DOI:10.1016/j.ijthermalsci.2012.06.014.
[10] Zhang H, Charmchi M, Veilleux D, et al. Numerical and experimental investigation of melting in the presence of a magnetic field: simulation of low-gravity environment[J]. Journal of Heat Transfer, 2007, 129: 568-576. DOI:10.1115/1.2709961.
[11] Wang Z H, Meng X, Ni M J. Liquid metal buoyancy driven convection heat transfer in a rectangular enclosure in the presence of a transverse magnetic field[J]. International Journal of Heat and Mass Transfer, 2017, 113: 514-523. DOI:10.1016/j.ijheatmasstransfer.2017.05.121.
[12] Okada K, Ozoe H. Experimental heat transfer rates of natural convection of molten Gallium suppressed under an external magnetic field in either the X, Y, or Z direction[J]. Journal of Heat Transfer, 1992, 114(1): 107-114. DOI:10.1115/1.2911234.
[13] Ghalambaz M, Doostanidezfuli A, Zargartalebi H, et al. MHD phase change heat transfer in an inclined enclosure: effect of a magnetic field and cavity inclination[J]. Numerical Heat Transfer, Part A: Applications, 2017, 71(1): 91-109. DOI:10.1080/10407782.2016.1244397.
[14] Feng Y C, Li H X, Li L X, et al. Investigation of the effect of magnetic field on melting of solid gallium in a bottom-heated rectangular cavity using the lattice Boltzmann method[J]. Numerical Heat Transfer, Part A: Applications, 2016, 69(11): 1263-1279. DOI:10.1080/10407782.2015. 1127732.
[15] Haddad Z, Iachachene F, Zidouni F, et al. Magnetic field effects on melting and solidification of PCMs in an isosceles triangular cavity[J]. Journal of Thermal Analysis and Calorimetry, 2022, 147(7): 4697-4709. DOI:10.1007/s10973-021-10857-5.
[16] Saha S K. Dynamics of phase change of gallium under magnetic field and thermocapillary effects under variable gravity conditions[J]. Thermal Science and Engineering Progress, 2022, 29: 101234. DOI:10.1016/j.tsep.2022.101234.
[17] Yamanaka Y, Kakimoto K, Ozoe H, et al. Rayleigh–Benard oscillatory natural convection of liquid gallium heated from below[J]. Chemical Engineering Journal, 1998, 71(3): 201-205. DOI:10.1016/S1385-8947(98)00100-4.
[18] 孙思睿, 张杰, 倪明玖. 横向磁场下侧壁加热方腔熔化的数值模拟研究[J]. 力学学报, 2022, 54(9): 2377-2386. DOI: 10.6052/0459-1879-22-155.
[19] Li M, Jiao Z J, Jia P. Melting processes of phase change materials in a horizontally placed rectangular cavity[J]. Journal of Fluid Mechanics, 2022, 950: A34. DOI:10.1017/jfm.2022.751.
[20] Okabe T, Miyanishi T, Miyagawa T, et al. Spatio-temporal measurement of natural convective heat transfer on melting process using infrared thermography[J]. International Journal of Heat and Mass Transfer, 2021, 181: 121882. DOI:10.1016/j.ijheatmasstransfer.2021.121882.
[21] Parsazadeh M, Malik M, Duan X L, et al. Numerical study on melting of phase change material in an enclosure subject to Neumann boundary condition in the presence of Rayleigh-Bénard convection[J]. International Journal of Heat and Mass Transfer, 2021, 171: 121103. DOI:10.1016/j.ijheatmasstransfer.2021.121103.
