Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Mechanical Engineering


Two basic types of fluid motion are known, laminar and turbulent flow. Laminar flow is characterized by essentially uniform flow of fluid particles and obedience to Newton’s Viscosity Law, ¬ƒ=µdu/dy. Many fluids have been found to have dynamic viscosities (µ) which are essentially constant and are considered to be properties of the fluid. The viscosities of gases can even be derived by the kinetic theory of gases and are found to be functions of the mean free path of individual molecules. Turbulent motion, on the other hand, can be described as a flow made up of macroscopic lumps of fluid which fluctuate in a random manner. Turbulent flows can be categorized under the following headings: (1) homogenous isotropic flow (characteristic of flows downstream of a screen), (2) “Wall turbulence (boundary layer of pipe flow) and (3) free turbulence (jets or mixing regions). The development of the hot-wire anemometer has permitted quantitative studies of the nature of turbulence, and forms the basis of the present experimental work. Corrsin,1* in 1947, developed equations enabling the measurement of both velocity and temperature fluctuations with a hot-wire anemometer, and his equations will be extended to the present case. The experimental investigation was carried out in a wind tunnel designed specifically for the study of a turbulent mixing region.

Library of Congress Subject Headings

Fluid mechanics
Air flow




South Dakota State University