College of Engineering -- University of Wisconsin-Madison
n the spring of 2000, Associate Professor Riccardo Bonazza (right, shown here with Assistant Scientist Mark Anderson, left, and Associate Instrumentation Specialist Paul Brooks, background) will use the college's new 200 mph wind tunnel in his new course, Applied Aerodynamics. The tunnel was the design project of EP undergraduate students Matt Orzewalla and Marti Gissel during their senior year.
The $85,000 wind machine is a gift from Greenheck Fan Corporation of Schofield, Wisconsin. Greenheck is a supplier of air movement and control equipment. Rockwell Automation donated the frequency drive to control the fan speed. The tunnel's test area is four feet wide and three feet tall and will allow students to test the performance of thin airfoils of varying aspect ratios over a range of wind speeds and angles of attack. Students taking Applied Aerodynamics will work in groups with each carrying out a detailed case study of one family of National Advisory Committee on Aeronautics (NACA) profiles. Students will compare the results of their measurements to those of their numerical calculations and to the theoretical predictions from the material covered in the prerequisite Engineering Mechanics & Astronautics 521--Aerodynamics.
The tunnel is equipped with three sets of airfoils (NACA 2412, NACA 23012, NACA 63212) each in three different aspect ratios with between 12 and 20 pressure taps on each airfoil and a 50-channel manometer bank; a sting balance equipped with a set of computer-controlled strain gauges; and a computer-based data acquisition system.
Bonazza and Associate Professor of Mathematics and Mechanical Engineering Leslie Smith also plan to develop a new research program for the study of turbulence related to turbomachinery flows. Velocity measurements from LDV and PIV systems will be used for comparison against the results of Smith's computational experiments.
Better devices, therapies hinge on bone mechanics
A better understanding of bone mechanics could lead to improvement in a wide array of medical devices and therapies for people and animals, from dental restoration and knee replacement to thoroughbred racing and better-designed milking parlors.
Wisconsin Distinguished Professor of Engineering Physics Roderic Lakes is studying the behavior of bone under stress, over time, otherwise known as viscoelastic behavior. Such behavior can manifest itself as creep, which is a gradual increase in strain under constant stress; stress relaxation, which is a gradual decrease in stress in a specimen held at constant strain; load-rate dependence of the stiffness; attenuation of sonic or ultrasonic waves; or energy dissipation in bone loaded dynamically.
Researchers have characterized each of the above phenomena in order to make a direct comparison of results based on the linear theory of viscoelasticity. In the case of shear deformation, there is good agreement between results obtained in different kinds of experiments, however, in the case of tension/compression there is significant disagreement among published results. Lakes is working to resolve this conflict.
Simpler and less expensive fusion devices
Never had a spherical torus research team achieved its first plasma so quickly. Culminating almost two years of intense construction efforts, engineering physics Professor Raymond Fonck and his team of students reached a major milestone by generating a plasma on one of the first tries. Researchers with the Pegasus Plasma Experiment are studying high-temperature plasmas (ionized gases) for applications to the development of fusion energy.
The goal of Pegasus is to explore theoretically predicted advantages of making the central hole in the "donut" as small as possible without losing the plasma to catastrophic instabilities. Fonck says this design allows the study of basic plasma physics concepts at high pressure, and in principle can lead to a much simpler and less expensive fusion device. He says generating a plasma so quickly represents a major step in the development of this type of magnetic confinement device.
"During the academic year, each student put in more than 10 hours per week in the laboratory, plus worked every Saturday and most holiday breaks," says Fonck. "Bringing the device from design to construction to operation on time and budget within the constraints of using a mainly student-based staff is an extraordinary achievement for the student team, and a testament to their hard work, talent and dedication."
Copyright 1999 University System Board of Regents
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