复合定形相变材料在沥青胶浆中的相变传热行为研究

The asphalt pavement in hot climates easily causes heat stability diseases, such rutting, translation, wave, bleeding and so on. At the same time, it not only pollutes environment but also aggregates the urban heat island effect, that is because it releases VOCs and releasing to rise environment temperature and worsen human being reside environment at high temperature. Based on phase change theory, organic solid-liquid phase change materials (PCM) as latent heat-storage material, inorganic porous materials as carrier, composite shape- stabilized phase change materials (CPCM) are prepared by physical blending method, which will replace fine aggregate of asphalt mixture and apply to asphalt pavement. Based on compatibility between CPCM and asphalt, the heat storage、temperature sensibility、rheological property and aging resistance of phase change asphalt mortar with adding CPCM are studied, the heat transfer behavior of CPCM in asphalt mortar is investigated, and the adjustment temperature mechanism of interaction between CPCM and asphalt mortar is studied by building phase change heat tranfer model. The theoretic foundation and technical support will be provide for the research and applications of phase change heat storage asphalt pavement materials, which will promote better application of PCM in asphalt pavement and alleviate high temperature diseases of asphalt pavement.

沥青路面在高温条件下易产生车辙、推移等热稳性病害，同时高温沥青路面释放的有机挥发物和大量热量既污染环境又加剧了城市热岛效应。本项目基于相变理论，拟选择有机固-液相变材料为工作物质，无机多孔材料为定形载体，通过物理共混法研制出一种适用于沥青路面且可替代沥青混合料细集料的复合定形相变材料。研究复合定形相变材料与沥青的相容性，相变沥青胶浆储热性能、温度敏感性、流变性能和耐老化性能，分析复合定形相变材料对沥青胶浆技术性能的影响；建立相变传热模型，探讨复合定形相变材料与沥青胶浆的交互作用的相变调温机制。该研究为相变储热沥青路面材料的开发与应用提供理论依据和技术支持，以更好地促进相变材料应用于沥青路面工程中，减缓沥青路面高温病害。

项目针对沥青路面在高温条件下易引发的热稳性病害和城市热岛效应问题，基于相变理论，研制出一种可替代沥青胶浆中矿粉的复合定形相变材料，实现主动调节沥青路面温度，并探讨其在沥青胶浆中的相变传热行为。.首先，根据相变材料在沥青路面工程中的研究与应用需求，基于相变理论和材料特性，优选出聚乙二醇（PEG）为相变材料功能单位，二氧化硅（SiO2）为无机定形载体，并采用温度促凝法制备出PEG/SiO2复合定形相变材料，从而获得相变温度匹配、相变焓高、热稳定性和定形效果良好的PEG/SiO2相变颗粒。.其次，将PEG/SiO2相变颗粒以不同质量比例掺入到沥青胶浆中，通过相变沥青胶浆储热性能、温度敏感性、流变性能和耐老化等性能以及微观结构表征试验，考察了相变颗粒对沥青胶浆技术性能的影响，分析了两者的相变传热行为和交互作用机理。结果表明，相变颗粒与沥青胶浆间仅仅是物理共混作用，化学兼容性良好，因而相变颗粒在沥青胶浆中仍然能够发挥其良好的相变储热作用，降低沥青胶浆的温度敏感性，与此同时还显著增强沥青胶浆的高温流变性能，高温稳定性得以增强，并且有效改善沥青胶浆的抗热氧老化能力。.最后，通过相变沥青胶浆的调温性能试验，获得不同质量掺量相变颗粒的沥青胶浆的温度数据，应用Fluent软件建立相变传热模型，结合相变传热模型计算与微观结构表征，分析其相变调温机制。.项目研究成果为相变沥青路面材料的开发与应用提供了理论依据和技术支持，以更好地促进相变材料应用于沥青路面工程中，减缓沥青路面高温病害。