• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.19 no.5
• /
• pp.411-417
• /
• 2007

This study has been conducted to investigate pumping characteristics of diffuser/nozzle based piezoelectric micropumps. The micropumps include a piezo disk (an actuator), a chamber and a set of diffuser and nozzle. Flow in the current micropumps is controlled by a set of diffuser and nozzle, not by a nap valve. The diffuser/nozzle based micropumps are more reliable in operation and are easier in manufacturing than the flap valve based micropumps. The flow rates of the piezoelectric micropumps have been closely analyzed with a numerical calculation. It has been found that the positions of the inlet and outlet of the micropump can influence the performance of the diffuser/nozzle based piezoelectric micropumps. This study may provide fundamental understanding for the design and analysis of the piezoelectric micropumps.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.8
• /
• pp.707-713
• /
• 2004

A numerical analysis has been conducted for flow characteristics of piezoelectric micropumps. In the present study, FSI (Fluid-Structure Interaction) model and grid deform model have been employed for each of two different geometries of the micropumps with two different frequencies in the piezoelectric diffuser/nozzle based micropumps. The displacement of piezo disk and flow rates have been closely examined at the inlet and outlet. It has been found that the motion of the piezo disk investigated with FSI model is not in accordance with that with grid deform model. The results show that the time averaged flow rate calculated with FSI model is larger than that with grid deform model. This study presents the performance analysis of piezoelectric micropumps with two different numerical models for different types of pumps.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.141-142
• /
• 2008

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.21 no.1
• /
• pp.33-40
• /
• 2009

In the present experimental study, the pumping performances of diffuser/nozzle based piezoelectric micropumps are estimated with different operating factors and geometries. Here, the effects of the input voltage and frequency on the pumping performances have been examined together with the influences of the positions of the inlet and outlet. The results show that the flow rate of the micropump is larger with larger input voltage with the largest flow rates for the frequency to be close to 6.0 Hz all through the current experimental study. Also, it has been found that the positions of the inlet and outlet affect much on the performance of the piezoelectric micropumps. Error estimation has been carried out for the evaluation of the pumping performance in association with the uncertainty of the measurement.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.34 no.6
• /
• pp.35-41
• /
• 2006

In this paper, we focus on improving the performance of the piezoelectric diaphragms of valveless micropumps. A circular lightweight piezoelectric composite actuator (LIPCA) with a high level of displacement and output force has been developed for piezoelectrically actuated micropumps. We used numerical and experimental methods to analyze the characteristics of the actuator to select optimal design. With the developed circular LIPCA, we fabricated a valveless micropump by photo-lithography and PDMS molding techniques. The displacement of the diaphragm, the flow rate and the back pressure of the micropump were evaluated and discussed. With a semi-empirical method, the flow rate with respect to driving frequency was predicted and compared with experimental one. The test results confirm that the circular LIPCA is a promising candidate for micropump application and can be used as a substitute for a conventional piezoelectric actuator diaphragm.

• Proceedings of the KSME Conference
• /
• 2005.11a
• /
• pp.140.1-140.1
• /
• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.595-596
• /
• 2008

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.345-348
• /
• 2006

The piezoelectric thick films were fabricated on silicon substrates by screen printing method. By developing a low-temperature sinterable piezoelectric composition and a new poling technique, we fabricated the high-performance piezoelectric thick films on silicon which can be applied for piezoelectric MEMS applications such as micropumps of the ink jet printer heads.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.17 no.1
• /
• pp.33-38
• /
• 2005

This study has been conducted to investigate flow characteristics of a micropump with piezoelectric materials. In this study, the change of flow rates has been investigated for different positions of the inlet and outlet and for different distances between them. The FSI(Fluid Structure Interaction) method has been employed for numerical analysis of the piezoelectric diffuser/nozzle based micropump. It has been found that time averaged flow rate is greater in the case that distance between the inlet and outlet is longer. For the cases where the positions of the inlet are different with the position of the fixed outlet at the center, the flow rate is increased as the inlet is located farther from the center. This study may supply fundamental understandings for the design and analysis of the prototypes of piezoelectric micropumps.

• Journal of the Korean Society for Precision Engineering
• /
• v.27 no.10
• /
• pp.84-92
• /
• 2010

In this study a numerical analysis has been conducted for the flow characteristics and pumping performance of a piezoelectric-based micropump with electromagnetic resistance exerted on electrically conducting fluid. Here, electromagnetic resistance is alternately applied at the inlet and outlet with alternately applied magnetic fields in association with the reciprocal membrane motion of the piezoelectric-based micropump. A model of Prescribed Deformation is used for the description of the membrane motion. The internal flow characteristics and pumping performance are investigated with the variation of magnetic flux density, tube size, displacement of membrane and the frequency of the membrane. It turns out that the current micropump has a wide range of pumping flow rate compared with diffuser-nozzle based micropumps.