微波场中加热高钛高炉渣的数值模拟

Numerical simulation on the heating of blast furnace(BF)slag with high TiO_2 under microwave irradiation

利用微波加热技术在高钛高炉渣内引发裂纹的实验过程中发现炉渣局部区域发生热失控现象。为探寻高钛高炉渣在微波场中产生热失控的原因,使用FEMAP和wave-jω软件计算了在多模式微波炉中高钛高炉渣及其周围空间内微波场和热三维分布情况,并对比研究了钙钛矿相和普通高炉渣吸收微波的能力。通过计算结果可知几乎所有的微波能都集中在被加热的高钛高炉渣试样中,即微波具有加热高钛渣自身而非周围环境的特点。另外,高钛高炉渣试样中微波场分布不均匀,且分散在炉渣中的钙钛矿相比其他矿物相更易被微波加热。以上2因素作用下微波加热高钛高炉渣时局部区域发生热失控现象。

In the process of heating BF slag with high TiO2 to induce crack by microwave irradiation,thermal runaway occurred locally.In order to explore the reason of thermal runaway,softwares of FEMAP and wave-jωwere used to calculate the 3D microwave field and thermal distribution in the sample and space around under multi-mode microwave oven.Furthermore,the ability of CaTiO3 phase and general BF slag to absorb microwave energy was compared.The calculation results show that almost all microwave energy is focused on the BF slag instead of the space around.In addition,the microwave field distribution in the BF slag sample is not uniform,and the CaTiO3 phase in the slag is heated more effectively than other mineral phases under microwave irradiation.The two factors above are the reasons for thermal runaway occurred in the BF slag bearing high TiO2 irradiated under microwave field.