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Actual Airflow vs. Ideal
Airflow: Stalls
FoilSim Activity
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Subject Area: Industrial Technology and Physics
Grade Level: 9-12
National Science Standards:
Science as Inquiry - develop an appreciation of
how we know what we know.
Physical Science - motions and forces interactions.
National Technology Standards:
Technology Research Tools - Select and apply
technology tools for research, information analysis,
problem-solving, and decision-making in content learning.
Technology Problem-Solving and Decision-Making Tools -
Routinely and efficiently use on-line information resources to
meet needs for collaboration, research, publications,
communications, and productivity.
Objectives:
After reading the explanation given below, use 3-D
modeling techniques to observe the characteristic signature of the
stall condition apparent on an airfoil at high angles of attack.
Compare this actual airflow to the ideal airflow depicted in
FoilSim and be able to explain the reasons for the results
obtained.
FoilSim is an interactive
simulation software package that examines the airflow around various shapes
of airfoils. As you change parameters such as airspeed, altitude, angle
of attack, thickness and curvature of the airfoil, and size of the wing
area, the software calculates the lift. The package was created at the NASA
Glenn Research Center.
FoilSim II is a Java applet program that executes inside the browser of your computer.
It is available on the World Wide Web at
http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.html.
You can also
download the program to run off-line.
Shown below is a screen
shot from the program's controls and displays. You may change the values
of the variables by using the slider or the input box on the left of the
slider.
To use the slider:
- Click the mouse
pointer on the arrows at the ends of the slider.
- Click the mouse
pointer anywhere between the slider and the arrow.
- Drag the slider
with the mouse.
To use the input
box:
Simply select the
value in the input box, key in the new value, and press Enter or Tab when
finished. The button on the slider will move corresponding to the value
typed in the box.
To begin the activity, click Stalls
Activity.
Assessment:
You, or you and your partner(s), will be evaluated on the
creation of the model airfoil used, with direct observation of
your resulting experiment by the instructor, and by completion of
the technical report following this activity.
Evaluation:
You will demonstrate the ability to use FoilSim to create
a model airfoil that will be tested in a wind tunnel for certain
angles of attack. The data will be used to explain differences in
actual and ideal airflow in correct report format.
Submitted by:
William Glynn, Brookside High School, Sheffield, Ohio
E-mail: billg@centuryinter.net
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