Abschlussarbeiten - Master
Investigation of Gas flow-regulation and -generation of active Microfluidik MEMS-Devices
Art der Abschlussarbeit
Master
Autoren
- Velmurugan, Surendran
Betreuer
- Prof. Dr.-Ing. habil. Wolf-Joachim Fischer
Weitere Betreuer
M.Sc. S. Uhlig (Fh IPMS)
Abstract
The thesis deals with the experimental characterization of two microdevices namely device A and device B. Both devices are driven using NanoElectrostatic Drives (NED) developed by Fraunhofer IPMS.
Device A is an acoustic-based type where the lateral movement of the microactuators sandwiched between the top inlet and bottom outlet apertures made it attractive to investigate as a gas flow regulating device. Pumping behaviour is limited in device A due to the lack of flow rectifying elements such as valves. In order to make fluidic interconnections, a fluidic housing encapsulating device A was designed. The microactuator in device A acts as a barrier to the inlet and outlet fluid path. In order to reveal details about the pressure needed to open the flow direction, it would be useful to examine the pressure-induced flow characteristics. The simulation showed that at least 90 kPa differential pressure should be overcomed by device A to deflect the microactuator 41 μm from its initial position towards outlet aperture and thereby opening the gas flow path.
Device B is an in-plane reciprocating displacement micropump with normally closed check valves. The microactuators are in an alternating curve shape that enables to attain higher deflection in the presence of actuation. In order to perform experiments with device B, there was a need to develop an adequate characterization environment. Device B had to be fluidically and electrically interfaced. To make fluidic connections to device B, a PDMS mat was designed. The PDMS comprises a fluidic passage for device B, also acting as a leakage-proof setup. Fraunhofer IPMS had designed fluidic housing for device B that encapsulates the PDMS component and device B together. The manipulators provide electrical connections from the backside of the device B. Device B was experimentally investigated for its flow regulation ability in a non-polar liquid using parameters such as pressure, actuation voltage and lower frequencies. The experimental analysis showed that for voltage between 70 V and 130 V, the flow rate in device A increases considerably. This is expected to show a good relation with a resistance ratio of 1.23 calculated from a simplified analytical model with resistance elements.
Device A is an acoustic-based type where the lateral movement of the microactuators sandwiched between the top inlet and bottom outlet apertures made it attractive to investigate as a gas flow regulating device. Pumping behaviour is limited in device A due to the lack of flow rectifying elements such as valves. In order to make fluidic interconnections, a fluidic housing encapsulating device A was designed. The microactuator in device A acts as a barrier to the inlet and outlet fluid path. In order to reveal details about the pressure needed to open the flow direction, it would be useful to examine the pressure-induced flow characteristics. The simulation showed that at least 90 kPa differential pressure should be overcomed by device A to deflect the microactuator 41 μm from its initial position towards outlet aperture and thereby opening the gas flow path.
Device B is an in-plane reciprocating displacement micropump with normally closed check valves. The microactuators are in an alternating curve shape that enables to attain higher deflection in the presence of actuation. In order to perform experiments with device B, there was a need to develop an adequate characterization environment. Device B had to be fluidically and electrically interfaced. To make fluidic connections to device B, a PDMS mat was designed. The PDMS comprises a fluidic passage for device B, also acting as a leakage-proof setup. Fraunhofer IPMS had designed fluidic housing for device B that encapsulates the PDMS component and device B together. The manipulators provide electrical connections from the backside of the device B. Device B was experimentally investigated for its flow regulation ability in a non-polar liquid using parameters such as pressure, actuation voltage and lower frequencies. The experimental analysis showed that for voltage between 70 V and 130 V, the flow rate in device A increases considerably. This is expected to show a good relation with a resistance ratio of 1.23 calculated from a simplified analytical model with resistance elements.
Schlagwörter
-
Berichtsjahr
2020