Performance Modeling and Efficiency Analysis for a Piezohydraulic Pump with Active Valves

Piezoelectric actuation is an expanding field that makes use of piezoelectric materials that have high power density as actuators. These actuation systems have the potential higher power density than the traditional servo motor technology. However, due to tiny strain of the piezoelectric materials, displacement amplification mechanism should be incorporated into design for most commercial applications. Piezohydraulic actuation provides an ideal amplification that can achieve any combination of stroke and force, which is superior than most other amplification technologies. The concept of piezohydraulic actuation takes advantage of the high force capabilities that piezoceramics have and combines it with the operation at high frequencies, in order to achieve the hydraulic actuation of a system under a specified stroke and force. In this research, a compact piezohydraulic pump with active valves has been developed, tested and characterized. Furthermore, theoretical models are developed based on different levels of approximation of the hydraulic fluid. The first model, which assumes an incompressible and inviscid fluid, provides us views of the basic features of piezohydraulic actuation. The second model which takes into account the viscosity of the fluid and the third model which takes into account both viscosity and compressibility of the fluid are then presented. Then, their simulation results are compared with experimental data, which shows the compressibility of the fluid is important to system performance. At last, a power and efficiency analysis based on experimental results is presented.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Mechanical Engineering

Department dc:contributor.department

Mechanical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2002

Author dc:creator

• Tan, Honghui

Chair dc:contributor.committeechair

• Leo, Donald J.

Committee members dc:contributor.committeemember

• Dancey, Clinton L.
• Robertshaw, Harry H.

• power
• compressible
• viscous
• piezo-hydraulic
• timing

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-12172002-111204

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/36223