rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Metal Mesh Foil Bearings
    sub title: Prediction and Measurement for Static and Dynamic Performance Characteristics
  name:
    name part: Chirathadam, Thomas Abraham
    role:
      role term: creator
    role:
      role term: author.
  name:
    name part: San Andres, Luis
    role:
      role term: thesis advisor.
  name:
    name part: Texas A & M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2013
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: remote
    extent: 1 online resource (178 pages)
  abstract: Gas bearings in oil-free micro-turbomachinery for process gas applications and for power generation (< 400 kW) must offer adequate load capacity and thermal stability, reliable rotordynamic performance at high speeds and temperatures, low power losses and minimal maintenance costs. The metal mesh foil bearing (MMFB) is a promising foil bearing technology offering inexpensive manufacturing cost, large inherent material energy dissipation mechanism, and custom-tailored stiffness and damping properties. This dissertation presents predictions and measurements of the dynamic forced performance of various high speed and high temperature MMFBs. MMFB forced performance depends mainly on its elastic support structure, consisting of arcuate metal mesh pads and a smooth top foil. The analysis models the top foil as a 2D finite element (FE) shell supported uniformly by a metal mesh under-layer. The solution of the structural FE model coupled with a gas film model, governed by the Reynolds equation, delivers the pressure distribution over the top foil and thus the load reaction. A perturbation analysis further renders the dynamic stiffness and damping coefficients for the bearing. The static and dynamic performance predictions are validated against limited published experimental data. A one-to-one comparison of the static and dynamic forced performance characteristics of a MMFB against a Generation I bump foil bearing (BFB) of similar size, with a slenderness ratio L/D=1.04, showcases the comparative performance of MMFB against a commercially available gas foil bearing design. The measurements of rotor lift-off speed and drag friction at start-up and airborne conditions are conducted for rotor speeds up to 70 krpm and under identical specific loads (W/LD =0.06 to 0.26 bar). The dynamic force coefficients of the bearings are estimated, in a "floating bearing" type test rig, while floating atop a journal spinning to speeds as high as 50 krpm and with controlled static loads (22 N)…
  note: by Thomas Abraham Chirathadam.
  note: "Major Subject: Mechanical Engineering"
  note: Includes vita.
  note: Doctor of Philosophy Texas A & M University 2012 http://hdl.handle.net/1969.1/148301
  note: Includes bibliographical references.
  note: Text (Dissertation)
  subject:
    topic: Major Mechanical Engineering
  subject:
    topic: Loss factor
  subject:
    topic: Damping
  subject:
    topic: Stiffness
  subject:
    topic: Bearing parameter identification
  subject:
    topic: Rotordynamics
  subject:
    topic: GFB
  subject:
    topic: Gas foil bearing
  subject:
    topic: MMFB
  subject:
    topic: Metal mesh foil bearing
  identifier: http://hdl.handle.net/1969.1/148301
  record info:
    record content source: TXA
    record creation date: 140113
    record change date: 20151206090949.0
    record identifier: in00003429970
    language of cataloging:
      language term: eng