结构参数对非对齐入口式T型微混合器内混合特性的影响

Influence of Geometrical Configurations on Mixing Performance in T-shaped Micromixer With Non-aligned Inputs

对非对齐入口式T型微混合器内流动与混合特性开展了三维数值模拟.结果显示,非对齐式入口的布置方式使流体流入通道时在重力方向上出现位移差,增大了流体的接触面积且沿通道轴向方向上出现明显的旋流状运动,从而进一步强化混合.同时,结合数值模拟和田口优化法对影响该微混合器混合性能的3个设计参数进行比较和分析,并结合信噪比的变化确定了非对齐入口式T型微混合器的最佳结构设计方案.这些参数对混合的影响强度分别为:入口通道宽度w>入口通道与主通道高度比h/H>入口通道入流角度α.

The flow and mixing performance of fluid in T-shaped micromixer with non-aligned inputs are investigated numerically by using a three-dimensional numerical simulation method. The analysis results show that the displacement differences appear in the direction of gravity due to the arrangement of non- aligned inputs. After fluid flowing into the channels, the fluid contact areas increase. The apparent spiral flows are generated along the axial direction of the channel, thus further strengthening mixing performance. Meanwhile, this paper presents a numerical design methodology for different geometrical configurations, which systematically integrates computational fluid dynamics （CFD） with an optimization methodology based on the use of Taguchi method. The geometric features of this micromixer geometry have been optimized based on the change of signal-to-noise ratio. The influence degree of parameters on mixing effectiveness is： width of the inlet channel w 〉 height ratio of inlet and main channels h/H 〉 inflow angle of the inlet channel .