基于CPD模型数据的煤粉单步热解模型

One Step Model of Coal Pyrolysis Based on CPD Model Data

基于化学逾渗脱挥发分(CPD)煤热解模型数据,以单步热解模型为基础建立了煤热解新单步模型.新模型的特点是指前因子与活化能随煤粉颗粒升温速率的变化而变化,而不再是常数;实际挥发分析出量同样与升温速率和热解温度相关联.利用实验数据对新模型进行了验证,并离线计算、比较了新模型与现有单步模型的计算结果.在此基础上,通过编写UDF将新模型添加到商业CFD计算软件Fluent平台上,利用新模型对煤热解实验结果进行了模拟与对比.结果表明,与Fluent默认单步模型相比,模拟得到的挥发分析出量及热解速率与实验结果更接近.

A new one step model of coal pyrolysis was developed based on original one step model andCPD（chemical percolation devolatilization）model data.The pre-exponential factor and activation energy of the newmodel are self-adapted to coal particle heating rate.The actual amount of volatile matter evolved from pyrolysis is alsorated to the coal particle heating rate and pyrolysis temperature.The new model was validated against pyrolysis experimentaldata and compared with original one step model and CPD model based on an off-line pyrolysis calculation.Based on this,the new model was implemented into Fluent by writing UDF（user defined function） successfully.Pyrolysis simulation at two temperatures were conducted by using this new model in Fluent.Compared with thedefault one step model in Fluent,the new model shows better agreement with experimental data both in volatileamount and pyrolysis rate.