Parameters influencing pulsed flow mixing in microchannels.
The rapid mixing of reagents is a crucial step for on-chip chemical and biological analysis. It has been recently suggested that microfluidic mixing can be greatly enhanced by simply using time pulsing of the incoming flow rates of the two fluids to be mixed (Glasgow, I.; Aubry, N. Lab Chip 2003, 3, 114-120). This paper elaborates on the latter technique, showing through computational fluid dynamics how the mixing efficiency strongly depends on certain dimensionless parameters of the system, while remaining nearly insensitive to others. In particular, it is demonstrated that higher Strouhal numbers (ratio of flow characteristic time scale to the pulsing time period) and pulse volume ratios (ratio of the volume of fluid pulsed to the volume of inlet/outlet intersection) lead to better mixing. This paper also presents a physical device capable of mixing two reagents using pulsing, which shows improved mixing with greater values of the Strouhal number.
New Jersey Center for Micro Flow Control and the Department of Mechanical Engineering, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, USA.
Ian
I
Glasgow
Samuel
S
Lieber
Nadine
N
Aubry
D003198:Computer Simulation; D007202:Indicators and Reagents; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity
D007202:Indicators and Reagents