PARTICLE SHADOW VELOCIMETRY IN THE WALL REGION OF A TURBULENT PIPE FLOW

Open Access
Author:
Braun, Tyler W
Area of Honors:
Mechanical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Arnold Anthony Fontaine, Thesis Supervisor
  • Michael H Krane, Thesis Supervisor
  • Matthew M Mench, Honors Advisor
Keywords:
  • particle shadow velocimetry
  • PSV
  • particle image velocimetry
  • PIV
  • flow measurement
  • pipe flow
Abstract:
Particle Shadow Velocimetry (PSV) is a digital particle image velocimetry (PIV) technique used to produce vector fields characterizing seeded fluid flows. PSV replaces the laser light source standard to PIV with a low-power, multicolor LED lamp and has many capabilities not demonstrated by other flow measurement techniques including a superior dynamic range, kilohertz sampling rates, and measurement of local accelerations. This thesis uses PSV to evaluate the flow field at the near wall of a turbulent, fully developed pipe flow in the Applied Research Laboratory’s boundary layer research facility in an attempt to develop practical understanding of the PSV system, validate the method through replication of scientifically accepted flow data, and evaluate the real-world acceleration capabilities of the technique. Results compared with previous LDV and PIV data indicate that both same-color and cross-color PSV provide accurate velocity profiles, but the chromatic aberrations that plague cross-color PSV slightly skew full-field velocity results and prevent acceleration measurements without further experimentation and processing refinement.