麻醉蒸发器内部流动与混合过程的三维数值计算分析

3-Dimentional Numerical Simulation on Internal Flow and Mixing Process of an Anesthesia Vaporizer

研究了某型麻醉蒸发器工作原理,并对其结构进行实际测量。运用CFD方法对蒸发器内部气体流动与混合过程进行了三维数值模拟分析,并采用湍流随机跟踪方法,对麻醉药物蒸发雾滴的运动进行轨迹追踪,得到了蒸发器内部气体速度场变化,麻醉药物挥发以及与稀释气体混合过程中浓度场变化等结果。根据计算结果发现,稀释气体在蒸发器内部流动过程中速度降幅较大,由于蒸发器几何结构因素,麻醉药物蒸发后与稀释气体的混合过程存在不均匀混合现象,即影响了最终蒸发药物浓度的稳定性与精确性,为此给出了麻醉蒸发器的设计优化方案。

The function theory of an anesthesia vaporizer was studied and the geometry configuration was measured in this study.The internal gas flow and mixing process in the anesthesia vaporizer were simulated using CFD method.Applying tracking in turbulent flow to stochastic particle,for the droplet of anesthesia drug,the moving track of droplet was traced.Based on the results,the internal gas flow variation,the concentration distribution of anesthesia drug volatilization process and mixing process with gas were ascertained.Numerical simulation results showed that,the diluted gas velocity reduction of internal flow in the anesthesia vaporizer was higher.Because of the anesthesia vaporizer geometry,the mixing process between anesthesia drug vapor and diluting gas was not homogeneous.This also influenced the stability and accuracy of anesthesia drug concentration.The optimization precept of anesthesia vaporizer is ascertained.