基于EDEM的煤仓卸料时煤散料流动特性分析

Analysis on flow features of bulk coal during coal unloading period based on EDEM

为研究煤仓卸料时煤散料流动特性和影响因素,使用离散元软件分析包EDEM建立了某型号煤仓与煤散料的分析模型,描述了EDEM建立煤仓模型、煤颗粒模型和生成煤散料的具体方法,模拟仿真了煤仓内煤散料卸料流动状态。结果表明:卸料过程为整体流逐步变为漏斗流;分别针对颗粒密度、散料含水率、粒径分布等煤散料参数,以及壁摩擦因数、卸料斗倾角、卸料斗口径等煤仓材料和结构参数,进行了卸料流态和速度影响因素分析,其中含水率越低,壁摩擦因数越小,卸料斗倾角与口径越大,则煤料流态越接近整体流,卸料速度越快,颗粒密度越大,粒径越大,卸料速度越快,但对煤料流态无明显影响。

In order to study flow features of bulk coal and influence factors during coal unloading period,discrete element software analysis pack-EDEM was applied to establish analysis model of mode coal bunker and bulk coal,to state certain methods to establish coal bunker model,coal partical model and bulk coal generation with EDEM. The results showed that coal unloading process would be changed from mass flow steadily to hopper flow. The analysis of unloading coal flow state and velocity influence factor was conducted to partical density,bulk coal water content,partical size distribution and bulk coal parameters as well as wall fraction factor,unloading hopper inclination,unloading hopper outlet diameter,coal bunker material and structure parameters individually. Among them,the higher water content was,wall fraction coefficient would be less small and the unloading hopper inclination and outlet diameter would be higher. When coal flow state was close to mass flow,the higher unloading velocity would be faster. The more larger the partical density and partical diameter was,the faster the unloading velocity would be and would not be affected to coal material flow state obviously.