Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-19T12:29:07.769Z Has data issue: false hasContentIssue false

Pressure Loading of Piezo Composite Unimorphs

Published online by Cambridge University Press:  01 February 2011

Poorna Mane
Affiliation:
[email protected], Virginia Commonwealth University, United States
Karla Mossi
Affiliation:
[email protected], Virginia Commonwealth University, 601 West Main St, PO Box 843015, Richmond, VA, 23284, United States
Robert Bryant
Affiliation:
[email protected], Nasa Langley Research Center, United States
Get access

Abstract

Over the past decade synthetic jets have emerged as a promising means of active flow control. They have the ability to introduce small amounts of energy locally to achieve non-local changes in the flow field. These devices have the potential of saving millions of dollars by increasing the efficiency and simplifying fluid related systems. A synthetic jet actuator consists of a cavity with an oscillating diaphragm. As the diaphragm oscillates, jets are formed through an orifice in the cavity. This paper focuses on piezoelectric synthetic jets formed using two types of active diaphragms, Thunder® and Lipca. Thunder® is composed of three layers; two metal layers, with a PZT-5A layer in between, bonded with a polyimide adhesive. Lipca is a Light WeIght Piezo Composite Actuator, formed of a number of carbon fiber prepreg layers and an active PZT-5A layer. As these diaphragms oscillate, pressure differences within the cavity as well as average maximum jet velocities are measured. These parameters are measured under load and no-load conditions by controlling pressure at the back of the actuator or the passive cavity. Results show that the average maximum jet velocities measured at the exit of the active cavity, follow a similar trend to the active pressures for both devices. Active pressure and jet velocity increase with passive pressure to a maximum, and then decrease. Active pressure and the jet velocity peaked at the same passive cavity pressure of 18kPa for both diaphragms indicating that the same level of pre-stresses is present in both actuators even though Lipca produces approximately 10% higher velocities than Thunder®.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Gad-el-Hak, M., Flow Control: Passive, Active, and Reactive Flow Management, 1st ed. (Cambridge University Press, United Kingdom, 2000), pp. 19.Google Scholar
2. Kral, L.D., Donovan, J.F., Cain, A.B., Cary, A.W., Numerical Simulation of Synthetic Jet Actuators, AIAA Conference, 971824 (1997).Google Scholar
3. Smith, B.L., Glezer, A., Vectoring and Small Scale Motions Effected in Free Shear Flows Using Synthetic Jet Actuators, AIAA, 970213 (1997).Google Scholar
4. Amitay, M., Honohan, A., Trautman, M., Glezer, A., Modification of the aerodynamic characteristics of bluff bodies using fluidic actuators, AIAA, 972004 (1997).Google Scholar
5. McLean, J.D., Crouch, J.D., Stoner, R.C., Sakurai, S., Seidel, G.E., Feifel, W.M., Rush, H.M., Study of the Application of Separation Control by Unsteady Excitation to Civil Transport Aircraft, NASA, Tech. Rep. CR1999 (1999).Google Scholar
6. Smith, B.L., Synthetic Jets and their Interaction with Adjacent Jets, Georgia Institute of Engineering, Ph.D. Thesis (1999).Google Scholar
7. Seifert, A., Bachar, T., Koss, D., Shepshelovich, M., Wygnanski, I., Oscillatory Blowing: A Tool to Delay Boundary-Layer Separation, AIAA J., 31(11), 2052 (1993).Google Scholar
8. Seifert, A., Darabi, A., Wygnanski, I., Delay of Airfoil Stall by Periodic Excitation, J. Air., 33(4), 691 (1996).Google Scholar
9. Crook, A., Sadri, A.M., Wood, N.J., The Development and Implementation of Synthetic Jets for the Control of Separated Flow, AIAA, 993176 (1999).Google Scholar
10. Mossi, K., Bryant, R., Pre-stressed Circular Actuators, Amer. Cer. Soc., pp. 445454 (2004).Google Scholar
11. Mossi, K., Bryant, R., R., , Piezoelectric Actuators for Synthetic Jet Applications, MRS Proceedings, 785, 407 (2004).Google Scholar
12. Mossi, K., Selby, G., Bryant, R., Thin-Layer Composite Unimorph Ferroelectric Driver and Sensor Properties, Mats Letters, 35, 39 (1998).Google Scholar
13. Yoon, K.J., Shin, S., Park, H.C., Goo, N.S., Design and Manufacture of Lightweight Piezoceramic Curved Actuator, Smart Mats. and Struct., 11, 163 (2002).Google Scholar
14. John, J. E.A., Gas Dynamics, 2nd edition (Allyn and Bacon, 1984), pp 180.Google Scholar