Behavior of microfluidic amplifiers

• Published in: Sensors and actuators. A. Physical. Vol. 51; no. 2; pp. 239 - 246
• Main Authors: Furlan, Rogério, Zemel, Jay N.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-11-1995
• Subjects: Choked flow; Microflow control; Microfluidic amplifiers; Silicon micromachining; Choked flow; Microfluidic amplifiers; Silicon micromachining; Microflow control
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/S0924-4247(96)01229-0

Two types of microfluidic amplifiers (wall-attachment and jet-deflection) have been implemented in silicon using standard micromachining methods and anodic sealing with a glass cap. The devices have areas of approximately 1 mm×0.5 mm and the complete structures with interconnection channels have areas of 12 or 18 mm×6 mm. Flow control and flow gain are demonstrated with supply pressures ranging up to 630 kPa, using dry nitrogen as the test fluid. An asymmetric output flow is observed from the two output ports at sufficiently high supply pressures in both devices, suggesting possible shock-wave formation. The jet-deflection microfluidic amplifier presents a more symmetric behavior and provides higher flow variation than the wall-attachment device. The ratio of the maximum and minimum output flows, as measured for the jet-deflection device for various control and supply pressures, reveals a performance degradation at the onset of choked supply flow.