硅酸铝纤维/酚醛树脂复合材料高温隔热性能研究

High-temperature Insulation Properties of Al_2(SiO_3)_3 Fiber/Phenolic Resin Composite Material

目的考察硅酸铝纤维/酚醛树脂复合材料的烧蚀性能、高温隔热性能,同时寻求一种有多重不同隔热材料的密闭体系在高温环境下含有化学热效应的热传导过程的数值解决方法。方法将硅酸铝纤维/酚醛树脂层压复合材料用于密闭体系隔热,利用酚醛树脂高温热分解吸热的特性实现材料主动抗高温隔热的目的。用2 cm厚的硅酸铝纤维/酚醛树脂板材考察其烧蚀隔热性能。制备多层隔热材料的密闭体系进行火烧试验,火烧试验过程测试耐高温隔热材料背面温度以考察材料的隔热情况。对密闭体系包含化学热的多重隔热体系作出"等效热效应"的假设,建立体系的偏微分方程热传导模型,利用Matlab软件对模型进行数值求解,通过数值求解结果与试验测试温度的对比,验证计算结果的准确性。结果 2 cm厚的硅酸铝纤维/酚醛树脂复合材料在敞开体系经120 min单面烧蚀,其背面温度保持在140℃以下且无破坏痕迹;火烧试验中测得的无机耐高温隔热材料热分解吸热延长了其热穿透时间,密闭体系热传导模型数值解与试验结果最大偏差为37%。结论硅酸铝纤维/酚醛树脂复合材料具有良好的耐烧蚀和高温隔热性,热等效假设在解决具有化学热效应的隔热体系的传热问题具有合理性和实用性。

The heat-resistant and high-temperature insulation properties of Al2（SiO3）3 fiber/phenolic resin composite material were investigated, and meanwhile a numerical solution to the heat conduction process containing chemical heat effects of a hermetical system with multilayer different heat insulation materials in high-temperature environment was searched. Al（SiO3）3 fiber/phenolic resin composite was prepared for heat insulation in the hermetical system, and the active high temperature resistant heat insulation goal of the material was achieved through the endotherm feature of the phenolic resin decomposing at high temperature. The heat insulation properties of the hermetical system with multilayer adiabatic materials were investigated through the fire test. Therein the hermetical system was fabricated with 20 mm thick A12（SiO3）3 fiber/phenolic resin material, and the temperature on the back side of the high temperature resistant adiabatic material was tested during the fire test to investigate the heat insulation property of the material. On the assumption that the decomposing heat of the phenolic resin is equivalent to a heat resource in the multilayer adiabatic system containing chemical heat in hermetical system, the heat conduction mathematic model of the hermetical system was established. The Matlab Partial Differential Equation Solver was employed to solve the problem numerically. The numerical results were compared to the test temperature to verify the accuracy of the calculation results. After 120 min of sided ablation in open system, the back surface temperature of Al2（SiO3）3 fiber/phenolic resin composite material with a thickness of 2 cm kept below 140 ~C and there was no sign of damage. As measured in the fire test, the endotherm feature of thermal decomposition of the inorganic high-temperature resistant adiabatic material extended the heat penetration time, and the maximum deviation of the numerical solution of the heat conduction model in hermetical system from the test result was 37%. Al2（SiO3）3 fiber/phenolic resin composite material has good ablation resistance and high-temperature heat insulation property, and the heat equivalence hypothesis is reasonable and practical in solving the heat conduction problem in heat-insulating system with chemical heat effects.