摘要
为了探索快速有效的数值计算方法用于研究等离子体射流中粉末群的热运动状态,本文采用格子玻耳兹曼方法计算等离子体射流,使用随机算法跟踪颗粒,模拟了等离子体射流中粉末的加热和运动。计算结果表明:颗粒温度的变化比速度快,颗粒高速区比高温区的范围大。离射流出口越近,沿射流横截面颗粒轴向平均速度和温度波动越大,能获得沿射流横截面方向温度速度较高且分布均匀的位置区间为距离射流出口150 mm^200 mm。实测的粒子温度与速度和计算结果吻合较好,验证了本模型的有效性。论文研究为等离子体加工工艺条件的制定提供了依据。
In order to find an effective simulation for plasma spray process and make further observation on the powder particles heating and moving, modeling study was performed concerning the motion and heating of the Fe-Cr-Ni alloy powder particles in the atmospheric plasma jet by adding a probabilistic algorithm model to track particles＇ tracks on the top of the developed Lattice Boltzmann （LB） plasma fluid model. The simulation results show the whole process by animation and indicate that the mixed model is suitable for the numerical calculation of plasma spraying process. The calculation is faster than that by the conventional method. Ascend and descend of average temperature of the particle is faster than that of average velocity. The closer the position to the exit of plasma jet, the more tempestuously axial speeds of particles along cross-section fluctuate. Under our technology condition, the high average axial speeds and temperatures of the Fe-Cr-Ni alloy powder particles with tiny undulation along the cross section appear within the domain 150 mm-200 mm away from the exit of plasma jet, which can be chosen by the spraying distance. The model and method proved to be valid when the simulation results were compared with the experimental data.
出处
《计算力学学报》
EI
CAS
CSCD
北大核心
2007年第4期403-407,共5页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金(50474053)资助项目
关键词
热等离子体
LB流动
随机算法
颗粒加热与运动
thermal plasma
LB fluid
probabilistic algorithm
particle heating and moving
