近壁球形颗粒的曳力特性研究
Investigation of Force on the Spherical Particle Moving Towards a Planar Wall
霍晓昱 1王军 1夏国栋1
作者信息
- 1. 北京工业大学,强化传热与过程节能教育部重点实验室暨传热与能源利用北京市重点实验室,北京 100124
- 折叠
摘要
本文研究了球形颗粒在近壁区域内的曳力特性,基于气体动理论方法推导得到了自由分子区内近壁颗粒沿垂直于平壁方向运动时所受曳力的表达式,其计算结果与直接蒙特卡洛模拟结果一致.计算并分析了动量适应系数、壁面温度等参数对近壁颗粒所受曳力的影响规律和机制.当壁面动量适应系数为零时,近壁效应消失;当壁面温度高于气体温度时,近壁效应使得颗粒所受曳力增大;当壁面温度低于气体温度且颗粒速度较小时,可能出现曳力方向与颗粒运动方向相同的情况.
Abstract
In the present paper,we theoretically study the drag force on a particle moving towards a wall in the free molecule regime.Based on the gas kinetic theory,the formula for the force acting on a near-wall spherical particle is derived,which is consistent with Direct Simulation Monte Carlo results.It is found that the near-wall effect cannot take effect for the vanishing momentum accommodation coefficient.If the wall temperature is higher than the gas temperature,then the drag force can be enhanced by the near-wall effect.For a lower wall temperature,the drag can be suppressed,and even change its direction(in the same direction with the particle velocity).
关键词
自由分子区/曳力/近壁效应/气体动理论Key words
free molecule regime/drag force/near-wall effect/gas kinetic theory引用本文复制引用
基金项目
国家自然科学基金(51776007)
北京市科技新星计划(Z191100001119033)
出版年
2024
NETL
NSTL
万方数据