MEEG636 Fluid Mechanics Measurements

TR 11 to 12:15; 109 Colburn

INSTRUCTOR

Topics to be covered

• Introduction to Measurements: Why we need experimentation, what quantities do we measure.

• Measurable quantities: Mean, fluctuating components. Reynolds decomposition for turbulent flow, turbulence closure problem.

• Error Analysis: How to improve experimental accuracy by optimal choice of recording instrument.

• Flow Visualization: Addition of foreign materials to flow; optical methods for compressible fluids.

• Differential pressure measurement: Pitot-static tube with micromanometer for velocity measurement.

• Hot-Wire Anemometry: Constant Current vs. Constant Temperature anemometers. heat transfer characteristics from wires. Linearization. Sensitivity analysis, errors.

• Laser-Doppler Anemometry: Discussion of lasers, optics, scattering from particles, electronic processing of Doppler signal, sensitivity, error analysis.

• Particle Image Velocimetry: Particle Tracking, Youngs fringe analysis, autocorrelation and cross-correlation analysis, diffraction theory, holography.

• Statistics and Signal Processing: Stochastic processes, spectra, correlation, time vs. frequency domains.

Laboratory Experiments

Experiments will be conducted in groups of three. However, each student will turn in a separate report. Students will perform a minimum of four lab exercises to gain hands-on experience with the following measurement techniques:

• Differential pressure anemometry
• Hot wire anemometry
• Laser-Doppler Anemometry
• Particle Image Velocimetry

Experiments pertain to the measurement of mean and rms velocity profiles in turbulent pipe flow at a Reynolds number of 10,000, the flow induced by an impeller in a continuously stirred tank reactor (CSTR) and others.

Term Paper

Each student will research a technique of his or her choice related to fluids measurement, collect information from the library and commercial vendors pertaining to that technique, assess the validity of the technique and present their results in the form of a term paper and an in-class Powerpoint presentation.