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Title: Active vibration control of rotating machinery with a hybrid piezohydraulic actuator system

Abstract

An integrated, compact piezohydraulic actuator system for active vibration control was designed and developed with a primary application for gas turbine aircraft engines. Copper tube was chosen as the transmission line material for ease of assembly. Liquid plastic, which meets incompressibility and low-viscosity requirements, was adjusted to provide optimal actuator performance. Variants of the liquid plastic have been prepared with desired properties between {minus}40 F and 400 F. The effectiveness of this hybrid actuator for active vibration control (AVC) was demonstrated for suppressing critical speed vibration through two critical speeds for various levels of intentionally placed imbalance. A high-accuracy closed-loop simulation, which combines both finite element and state space methods, was applied for the closed-loop unbalance response simulation with/without AVC. Good correlation between the simulation and test results was achieved.

Authors:
;  [1]; ;  [2]
  1. Texas A and M Univ., College Station, TX (United States)
  2. National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
169989
Report Number(s):
CONF-940626-
Journal ID: JETPEZ; ISSN 0742-4795; TRN: IM9605%%8
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Engineering for Gas Turbines and Power; Journal Volume: 117; Journal Issue: 4; Conference: 39. international gas turbine and aeroengine congress and exposition, The Hague (Netherlands), 13-16 Jun 1994; Other Information: PBD: Oct 1995
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; MECHANICAL VIBRATIONS; CONTROL; GAS TURBINE ENGINES; COMPUTERIZED SIMULATION; RESPONSE FUNCTIONS

Citation Formats

Tang, P., Palazzolo, A.B., Kascak, A.F., and Montague, G.T.. Active vibration control of rotating machinery with a hybrid piezohydraulic actuator system. United States: N. p., 1995. Web. doi:10.1115/1.2815463.
Tang, P., Palazzolo, A.B., Kascak, A.F., & Montague, G.T.. Active vibration control of rotating machinery with a hybrid piezohydraulic actuator system. United States. doi:10.1115/1.2815463.
Tang, P., Palazzolo, A.B., Kascak, A.F., and Montague, G.T.. Sun . "Active vibration control of rotating machinery with a hybrid piezohydraulic actuator system". United States. doi:10.1115/1.2815463.
@article{osti_169989,
title = {Active vibration control of rotating machinery with a hybrid piezohydraulic actuator system},
author = {Tang, P. and Palazzolo, A.B. and Kascak, A.F. and Montague, G.T.},
abstractNote = {An integrated, compact piezohydraulic actuator system for active vibration control was designed and developed with a primary application for gas turbine aircraft engines. Copper tube was chosen as the transmission line material for ease of assembly. Liquid plastic, which meets incompressibility and low-viscosity requirements, was adjusted to provide optimal actuator performance. Variants of the liquid plastic have been prepared with desired properties between {minus}40 F and 400 F. The effectiveness of this hybrid actuator for active vibration control (AVC) was demonstrated for suppressing critical speed vibration through two critical speeds for various levels of intentionally placed imbalance. A high-accuracy closed-loop simulation, which combines both finite element and state space methods, was applied for the closed-loop unbalance response simulation with/without AVC. Good correlation between the simulation and test results was achieved.},
doi = {10.1115/1.2815463},
journal = {Journal of Engineering for Gas Turbines and Power},
number = 4,
volume = 117,
place = {United States},
year = {Sun Oct 01 00:00:00 EDT 1995},
month = {Sun Oct 01 00:00:00 EDT 1995}
}
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  • Vibration problems in rotating machinery are a major contributor of forced or unplanned maintenance outages in fossil fuel fired power plants. Many turbine blade failures, the leading cause of steam turbine outages for large fossil fuel plants in the United States, are caused by vibration-related fatigue stresses. Such failures cost utilities more than $235 million annually. However, conversion of large units to cycling operation also has increased blade failures. Lateral and torsional vibrations in turbines, generators, pumps, fans, and motors also cost utilities more than $170 million annually. Rotor dynamic instability and hydrodynamic forces induced by the working fluid andmore » by coupled mechanical-hydraulic interactions cause vibrations that can damage rotor, bearings, and seals and adversely affect foundation, piping, and ductwork. This paper discusses a series of troubleshooting tools to help utilities determine the root causes of turbine blade and other rotating machinery failure.« less