Optimization of electroosmotic micropump channel design based on COMSOL multiphysics

Aiming at the zone broadening problem caused by the bend effect in microfluidic chip capillary electrophoresis, this paper constructs a coupled model of current field-peristaltic flow field-dilute matter transfer field based on COMSOL Multiphysics. It is shown that the bending effect originates from the uneven distribution of flow velocity caused by the difference between the inner and outer paths and the electric field strength. Through the gradient optimization algorithm to adjust the control point of Bessel curve, the reconstruction scheme of the bend channel with adjusted shrinkage ratio is proposed. After optimization, the flow velocity ratio between the inner and outer sides of the channel is reduced from 2.75 to 1.08, which effectively eliminates the phenomenon of tilted sample zones. At the same time, the optimized structure significantly reduces the dispersion of the zones, and the peak concentration is increased to 42% of the initial value, which can effectively inhibit the sample tilt and concentration distortion. The research results provide a theoretical basis and optimization method for the design of high-performance microfluidic electrophoresis chips.