未点燃卷烟通风率的计算流体力学分析

Computational fluid dynamic(CFD)simulation of ventilation rate of an unlit cigarette

为了研究不同卷烟材料参数对卷烟通风率、吸阻以及卷烟内部气体速率分布变化的影响,采用计算流体力学(CFD)算法,结合卷烟材料阻力特性测试结果,对8种不同材料参数的试样卷烟进行了仿真分析并与实测结果进行了比对.结果表明:①对无滤嘴通风卷烟,卷烟纸透气度每增加20 CU,就会增加约4%的空气从卷烟纸进入烟支内部.②与无滤嘴通风卷烟相比,滤嘴通风将使卷烟纸进气量减少2%~3%,通过通风孔的最大气流速度可达0.83 m/s.③滤嘴通风、高透气卷烟纸以及使用沟槽滤棒均能改变卷烟纸进气量分布,使更多的空气倾向于从烟支后半段进入卷烟内部.④沟槽滤棒沟槽内的空气流速最高可达3.9 m/s,是其他部分流速的近10倍.

To investigate the influences of different cigarette material parameters on pressure drop,ventilation rate and air velocity distribution within an unlit cigarette,eight cigarettes with different material parameters were simulated by using a Computational Fluid Dynamics(CFD)method with experimental results from the test cigarette materials.The simulated values were compared with the measured values.The results showed that:1)For cigarettes without filter ventilation,about 4%of additional amount of air entered the cigarette through cigarette paper when the air permeability of cigarette paper increased by 20 CU.2)Comparing with cigarettes without filter ventilation,filter ventilation reduced the air intake through cigarette paper by 2%-3%,and the maximum air velocity through the ventilation holes reached 0.83 m/s.3)Filter ventilation,cigarette paper with high permeability and grooved filter changed the distribution of air intake through cigarette paper,so that more air tended to enter the cigarette from its rear half part.4)The maximum air velocity in the grooves of a grooved filter reached 3.9 m/s,which was 10 times of that in the other parts.