A panel heating terminal with photovoltaic direct drive electric heating phase change heat storage wall panel heating terminal is proposed
which uses photovoltaic DC to drive the electric heating film to produce heat and store the heat in the phase change material at the same time. The heat transfer model is established by using the multi physical field coupling software COMSOL
and the effect of adding flat fins (fin spacing
length and thickness) on the heat transfer process of phase change heat storage wall panel under natural convection conditions is discussed. The results show that properly reducing the fin spacing can effectively shorten the complete melting time of PCM
improve the average heat storage rate
and extend the heat release time
but the effect is not obvious. When the fin spacing is less than 25 mm
the total heat storage decreases significantly; Under the same fin spacing
the greater the proportion of fin length to the radial length of PCM
the higher the heat storage rate; When the thickness is 1 mm
the average heat storage rate reaches the maximum of 103.3 kJ/h
which increases by 27.2% compared with the structure without fins.
LI J Z, LIU P, LI Z.Optimal design and techno-economic analysis of a solar-wind-biomass off-grid hybrid power system for remote rural electrification: a case study of West China[J]. Energy, 2020, 208: 118387.
JEONG Y G, AN J E.UV-cured epoxy/graphene nanocomposite films: preparation, structure and electric heating performance[J]. Polymer international, 2014, 63(11): 1895-1901.
LU P B, CHENG F, OU Y H, et al.A flexible and transparent thin film heater based on a carbon fiber/heat-resistant cellulose composite[J]. Composites science and technology, 2017, 153: 1-6.
PRABAKARAN R, DHAMODHARAN P, SATHISHKUMAR A, et al.An overview of the state of the art and challenges in the use of gelling and thickening agents to create stable thermal energy storage materials[J]. Energies, 2023, 16(8): 3306.
FARAJ K, KHALED M, FARAJ J, et al.A review on phase change materials for thermal energy storage in buildings: heating and hybrid applications[J]. Journal of energy storage, 2021, 33: 101913.
SOARES N, GASPAR A R, SANTOS P, et al.Experimental evaluation of the heat transfer through small PCM-based thermal energy storage units for building applications[J]. Energy and buildings, 2016, 116: 18-34.
GOVINDARAJ K, PANCHABIKESAN K, DENKENBERGER D, et al.Effect of fin orientations in a spherically encapsulated PCM for effective heat transfer enhancement[J]. Chemical engineering transactions,2017, 277-282.
ZHANG L X, ZHANG Z Y, YIN H.Comprehensive study on melting process of phase change material by using paraffin coupled finned heating plate for heat transfer enhancement[J]. Sustainability, 2022, 14(5): 3097.
ZHAO C R, WANG J Y, SUN Y B, et al.Fin design optimization to enhance PCM melting rate inside a rectangular enclosure[J]. Applied energy, 2022, 321: 119368.
SHEIKHOLESLAMI M, AL-HUSSEIN H R A. Analyzing efficiency of solar heat storage unit within a building including Trombe wall equipped with phase change material in existence of fins[J]. Journal of building engineering, 2023, 71: 106406.
MI X, CHEN C, FU H Q, et al.Experimental study on heat storage/release performances of composite phase change thermal storage heating wallboards based on photovoltaic electric-thermal systems[J]. Energies, 2023, 16(6): 2595.
ROYON L, KARIM L, BONTEMPS A.Thermal energy storage and release of a new component with PCM for integration in floors for thermal management of buildings[J]. Energy and buildings, 2013, 63: 29-35.
LIANG Y X, WANG D J, LI Y, et al.Novel approach to remote rural heating: Direct coupled photovoltaic electric heater underfloor heating system with phase change materials[J]. Applied thermal engineering, 2024, 250: 123525.