is a beta 1.0g version of the TunnelSys Design Applet program, and you are invited
to participate in the beta testing. If you find errors in the program or
would like to suggest improvements, please send an e-mail to Thomas.J.Benson@nasa.gov.
TunnelSys - Design Applet
With this software
you can investigate the design of a wind tunnel model
by changing the geometry of a representative wing model.
is a series of three Java applications which students can use to
explore the process of
wind tunel testing.
In wind tunnel testing, an engineer must first design and build a wind tunnel
with all of the appropriate instrumentation included.
The model is then placed in the tunnel
and air is blown over the model.
The instrumentation records the desired information for the model designer.
The engineer who conducts the wind tunnel test is
not normally the same person who designed the model, but someone who is a specialist
at wind tunnel operation.
The data from the test normally goes to a third engineer who performs the necessary
data reduction and produces performance plots for the initial engineer.
To demonstrate the process used to conduct wind tunnel testing, we have produced an
applet version of TunnelSys.
Because of security limitations with Java, you can not save designs or results produced
with the applet version. The full application version does permit a team of students
to work on the various systems engineering aspects of wind tunnel testing.
The applet at the top of this page is the Design portion of the TunnelSys applet
and application. It is presented here so that students can gain familiarity with
the design part of the process.
This version of the Design applet includes an on-line user's manual which describes the
various options available in the program and includes hyperlinks to
pages in the
Beginner's Guide to Wind Tunnels
describing the math and science of wind tunnels.
More experienced users can select a
version of the program which does not include
these instructions and loads faster on your computer.
You can download these versions of the program to your computer
by clicking on this yellow button:
With the downloaded version, you can run the program off-line and do not
have to be connected to the Internet.
This program is designed to be interactive, so you have to work with the program.
There are a variety of choices which you must make regarding the display
of results by using a choice box.
A choice box has a descriptive word displayed and an arrow at the right of the
box. To make a choice, click on the arrow, hold down and drag to
make your selection.
The current values of the design variables are presented to you in boxes. By convention,
a white box with
black numbers is an input box and you can change the value of the number.
A black box with
yellow numbers is an output box and the value is computed by the program.
To change the value in an input box, select the box by moving the cursor into the box
and clicking the mouse, then backspace over the old number, enter a new number,
then hit the Enter key on your keyboard. You must hit Enter
to send the new value to the program.
For most input variables you can also use a slider located next to the input box.
Click on the slider bar, hold down and drag the slider bar to change values, or
you can click on the arrows at either end of the slider.
At any time, to return to the original default conditions,
click the yellow Reset button at the lower left of the program.
If you see only a grey box at the top of this page, be sure that Java is
enabled in your browser. If Java is enabled, and you are using the Windows XP
operating system, you need to get a newer version of Java. Go to this link:
try the "Download It Now" button, and then select "Yes" when the download box from Sun pops up.
If you experience difficulties when using the sliders to change variables,
simply click away from the slider and then back to it.
the arrows on the end of the sliders disappear, click in the areas
where the left and right arrow images should appear, and they
program screen is divided into three main parts:
top left side of the screen is the View Window.
The view window includes a graphic of the wing model that you are
designing and a slider which control the graphic.
Details of the window
are given in the Graphics section of this page.
right side of the screen is an Engineering Drawing of your model.
The size and scale of the model is given at the bottom of the panel.
Clicking on the words "Double" and "Half" will change the size of
lower left side of the screen is the Input/Output Panel.
Details of the variables
are given below.
The View Window contains a computer drawing of the wing model that
you are designing and some controls for the schematic drawing.
You can move the picture within the window by moving the cursor into
the window, holding down the left mouse button, and dragging the model
to a new location. You can also "Zoom" in close to the model by using
the green slider at the left of the window. If you get lost, pushing
the yellow Find button will return the model to the initial position.
The input/output variables
are located on the panel that is displayed at the lower left.
There are five input variables; the type of airfoil, the camber (curvature),
thickness, chord, and span of the wing.
The meanings of these terms are described on the
web page of the Beginner's Guide.
As you vary any of the input variables, the resulting geometry is shown in the
view window and the drawing window. Output from the program includes the
wing projected area and the aspect ratio which are also defined on the geometry page.
Calculations can be performed in either Imperial or Metric units by using the choice button
at the bottom of the page.
The Education Programs
Office will continue to improve and update TunnelSys based on user input.
Changes from previous versions of the program include:
On 5 Aug 09,
version 1.0g was released. This is the first released version
of the program. This version was derived from the application version by
Anthony Vila of Vanderbilt University during a summer intern session at NASA Glenn.