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: Behavior of Turbulent Structures within a Mach 5 Mechanically Distorted Boundary Layer
  name:
    name part: Peltier, Scott Jacob
    role:
      role term: creator
    role:
      role term: author.
  name:
    name part: Bowersox, Rodney D. W.
    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.
  abstract: High-resolution particle image velocimetry (PIV) is employed to resolve the velocity fields within a Mach 4.9 mechanically distorted turbulent boundary layer (Reθ H 40,000). The goal of this study is to directly observe the mechanisms responsible for the modified turbulent stresses present in mechanically distorted boundary layers. This is achieved by measuring the effects of the mechanical distortions upon the distribution, population, size, orientation, and energy content of the turbulent structures, and how the perturbed state of these structures is manifested within the ensemble-averaged turbulent stresses. The two mechanical distortions under investigation are 1) streamline curvature-induced favorable pressure gradients (Ip = {-0.08; -0.49}), and 2) periodic arrays of diamond roughness (k/δ H 0.07). A smooth-wall, flat-plate boundary layer is also included to establish the unperturbed state of the turbulent structures. The response of the mean turbulence statistics is investigated through ensemble-averaged profiles of Reynolds stresses, indicating the respective influences of pressure gradient effects and surface roughness upon the turbulent statistics. The distortion and reorientation of the large-scale coherent motions is quantified through the determination of the integral length scale and local structure angle from two-point correlations. Detection of individual vortices through the swirling strength criterion λci allows the population distribution of the turbulent eddies to be examined, along with the conditionally averaged hairpin structure. The baseline and rough-wall stresses showed good agreement when scaled by the smooth-wall friction velocity. Two-point correlations indicate that the reorientation of the large-scale [i.e. O(δ)] coherent structures, coupled with the modified wall-normal fluctuations, is primarily responsible for the modification of the rough-wall Reynolds stresses. The reduced Reynolds stresses observed in the favorable pressure gradi…
  note: by Scott Jacob Peltier.
  note: "Major Subject: Aerospace Engineering"
  note: Includes vita.
  note: Doctor of Philosophy Texas A & M University 2013 http://hdl.handle.net/1969.1/151397
  note: Includes bibliographical references.
  note: Text (Dissertation)
  subject:
    topic: Major Aerospace Engineering
  subject:
    topic: boundary layer
  subject:
    topic: turbulence
  subject:
    topic: coherent structures
  identifier: http://hdl.handle.net/1969.1/151397
  record info:
    record content source: TXA
    record creation date: 140327
    record change date: 20151206092828.0
    record identifier: in00003454128
    language of cataloging:
      language term: eng