The development of a natural convection heat transfer research facility

The Mechanical and Aerospace Engineering Department of the University of Tennessee, Knoxville, has dedicated a laboratory exclusively to the study of natural convection heat transfer. A major decision in the development of the laboratory was to employ optical instrumentation whenever possible. Thus, a Mach-Zehnder interferometer (MZI) is used for measuring fluid temperatures, a laser doppler velocimeter (LDV) for measuring fluid velocities, and a Wollaston prism interferometer for measuring heat fluxes at fluid-solid interfaces.

The basic objectives accomplished in the performance of the thesis project are:

(1) The development and documentation of the detailed experimental procedures required for using the Mach-Zehnder interferometer and laser doppler velocimeter to make measurements in natural convection flows,

(2) The design end construction of the -experimental apparatus necessary for an investigation of optimal enclosure shapes for internal natural convetion flows, and

(3) The application of the experimental procedures developed for the Mach-Zehnder interferometer and laser doppler velocimeter to measure the velocity and temperature profiles in the optimal enclosure shape apparatus when this apparatus was assembled in the form of a two-dimensional square enclosure with isothermal vertical walls end adiabatic horizontal walls.

An additional experiment was performed using the natural convection flow on a vertical, constant-heat-flux plate to check the accuracy of determining wall heat fluxes from temperature profiles measured with the Mach-Zehnder interferometer.

In summary, this thesis:

(1) Describes the operation, in both theory and practice, of the MZI and LDV,

(2) Presents the design and construction details of the two experimental devices,

(3) Lists the detailed procedures for setting-up the experiments and taking the required data,

(4) Explains and illustrates with examples the data reduction procedures, and

(5 ) Presents the results of the experiments along with an uncertainty analysis.