Experimental Investigations on the Thermal Performance and Phase Change Hysteresis of Low-Temperature Paraffin/MWCNTs/SDBS Nanocomposite via Dynamic DSC Method
Experimental Investigations on the Thermal Performance and Phase Change Hysteresis of Low-Temperature Paraffin/MWCNTs/SDBS Nanocomposite via Dynamic DSC Method
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DOI：
10.2139/ssrn.3927618
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发表时间：
2022-02
期刊：
影响因子：
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通讯作者：
Lu Liu;Xuelai Zhang;Xiangwei Lin
中科院分区：
文献类型：
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作者：
Lu Liu;Xuelai Zhang;Xiangwei Lin
相变材料具有理想的热性能，已成为热能储存的重要标志。由于相变材料的相变是非等温的，相变滞后现象尤为突出。本文制备了一种石蜡基纳米复合相变材料，将多壁碳纳米管（MWCNTs）与十二烷基苯磺酸钠（SDBS）复合，以提高其导热性和悬浮稳定性。通过一系列表征，PA/MWCNTs/SDBS复合相变材料具有良好的化学相容性、较好的储热性能、较高的充放热效率以及较好的热稳定性和循环稳定性。此外，通过差示扫描量热法（DSC）研究了温度范围、温度变化速率和样品质量对滞后度的影响。此外，还从相变材料的储能、温度延迟、热阻、结晶度和界面自由能等方面对相变材料的相变机理进行了解释。结果表明，PCH现象是可控的，从而提高了相变材料的能量利用效率。结果表明，所制备的PA/MWCNTs/SDBS复合相变材料的相变温度为5.5 °C，相变潜热为222.7Jg-1，导热系数为0.3727Wm-1 K-1，具有较大的应用潜力。
Phase change materials (PCMs) with ideal thermal property, has become a critical hallmark in thermal energy storage (TES). The phase change hysteresis (PCH) phenomenon is particularly prominent since the phase transition of PCM mixture non-isothermal. In this paper, a paraffin-based nanocomposite PCM were prepared, the multiwalled carbon nanotubes (MWCNTs) and sodium dodecyl benzene sulfonate (SDBS) were comprised for the enhancement of thermal conductivity and suspension stability. The PA/MWCNTs/SDBS composite PCM exhibited excellent chemical compatibility, better thermal storage capacity, high thermal charging and discharging efficiency, and preferable thermal and cyclic stability through a series of characterization. Furthermore, the differential scanning calorimetry (DSC) was performed to investigate the association of temperature range, temperature changing rate, and sample mass on hysteresis degree. Besides, the causes of PCH were interpretated from the respective of energy storage, temperature delay, thermal resistance of PCMs, crystallinity, and interfacial free energy. The results showed that PCH phenomenon is controllable, thereby improving the energy utilization efficiency of PCMs. Namely, the prepared PA/MWCNTs/SDBS composite PCM with suitable phase transition temperature of 5.5 °C, high latent heat of 222.7 J g -1 , and thermal conductivity of 0.3727 W m -1 K -1 , possesses enormous potential in large-scale applications.