A numerical analysis of non-Newtonian fluid flow through a valveless micropump

The flow behavior and performance parameters of a diffuser-nozzle element of a valveless micropump have been studied for different peak pressures by numerical analysis. Blood, a non-Newtonian fluid material has been taken as the working fluid of which viscosity is modeled by the Carreau Model. A pulsating pressure imposed at the boundary of the element results in a net flow in the diffuser direction due to the dynamic effect. The variation of performance parameters such as net volume flow rate, rectification capability and diffuser efficiency have been observed for quantitative study. Flow behavior and recirculation region have been studied as qualitative study. A 2-D geometry is considered for the numerical analysis and peak pressure has been varied from 5 to 50 kPa for the present study. Net volume flow, rectification capability and diffuser efficiency are found to increase with the increase of peak pressure. Flow separation and recirculation region are found to last for longer period of time with the increase of peak pressure.