【摘要】 在考虑材料烧蚀时参数变化及蜂窝夹芯传热能力变化的情况下,给出了激光烧蚀蜂窝夹芯复合材料的计算模型,并实验验证了模型的合理性。以碳纤维/环氧树脂-nomex蜂窝夹芯-玻璃纤维/环氧树脂复合材料为例,编程计算了材料的激光烧蚀过程,并以背表面温度为目标物理量进行了参数敏感性分析。计算结果表明,热导率及材料发射率是高敏感参数,热导率与背表面温度正相关,材料发射率与背表面温度负相关,激光功率密度越高,热导率及材料发射率的温度敏感度越高;纤维的升华可降低材料升温速率;对耐高温的蜂窝材料,激光烧蚀过程计算中,不仅要考虑背表面温度,还需要考虑热辐射功率密度。更多还原

【Abstract】 The paper presents a computational model of ablation of the honeycomb sandwich composite materials by laser beam. In this model, the variations of material parameters during ablation have been considered. As an example, the laser ablation process of carbon /epoxy-nomex honeycomb-glass /epoxy composite has been simulated. Taking the rear surface temperature as an object,the parameter sensitivity analysis has been completed. The results indicated that thermal conductivity and emissivity are the highly sensitive parameters, and there is a positive correlation between the rear surface temperature and thermal conductivity, and a negative correlation between the rear surface temperature and emissivity. The relative sensitivities of the two parameters increase with the laser power density. The material sublimation can slow down the rising rate of the rear surface temperature; besides the rear surface temperature, the thermal radiation power density should be also considered in the simulation of heatresistant honeycomb composites.更多还原