General Information



Post Test

Test Section



Hessert Laboratory for Aerospace Research at Whitefield

3x3 Wind Tunnel

General Information

The wind tunnel is located in the Wind Tunnel building located in the area known as White Field at the University of Notre Dame.  The tunnel is closed loop and capable of achieving a flow velocity of Mach 0.6 with a 5% blockage in a 3’ x 3’ (nominal) test section at an air temperature of approximately140ºF.  The operational times for the tunnel are dependent upon the velocity required for the test.  Generally, it can be operated at almost any time with velocities under Mach 0.4. Mach numbers higher than that may be attained during off peak power time from 9:00pm to 6:00am on week days and from 9:00pm Friday to 6:00am Monday morning. The tunnel is not operated on home football Saturdays.

Procedure for Scheduling Tunnel Time

To schedule time for use of the tunnel requires three steps. 

First, contact the Facility Manager (Robert Chlebek) , providing all the information of the test.

  1. The speeds required,
  2. How many days of testing will be necessary,
  3. Any special equipment that will be needed or any special services such as compressed air, auxiliary power, etc. 

Second, the test configuration details must be submitted to the Safety Review Committee (Rodney McClain), identifying critical points that might be of concern, particularly points of failure that might result in any breakage on model or unintended injection of material into the tunnel’s air stream. As there may be large loadings on the model, especially at high speeds, the experimenter shall provide to the Safety Committee a conservative estimate of the peak static and dynamic loads anticipated on the model and its supports. Models will not run in the wind tunnel if the factor of safety is less than two.

This must be submitted for review at least two weeks prior to test initiation.  In more sophisticated models, especially those employing external electro-mechanical operators to provide a dynamic test of the model, a longer review period may be required.

Third, after the Safety Review Committee reviews the submittal, a meeting will be scheduled to review the procedure, analysis, and any changes that may be necessary.  The experimentation team must be available to answer any questions that the committee may have, either in person on via conference call.  If the committee’s concerns are not satisfied the test may be rescheduled until the concerns are satisfactorily addressed.

The earlier that a description of the model, and associated apparatus, is submitted for initial review the less probable that issues that might force a partial design change can be avoided.

Performing the Test

Upon satisfactorily meeting all of the pretest requirements of the “Procedure for Scheduling Tunnel Time,” the experimenter should immediately speak with Rob Chlebek or Rod McClain, the tunnel operators, as to when the test can actually be performed.  This will be based on the speed involved and whether there are other issues that may delay the anticipated start time.  The tunnel operator assigned for the testing period will have the final say as to whether the experiment will be run at the specified time.  If the operator, upon inspection of the tunnel and the experiment’s installation, or anything that happens during the actual tunnel’s operation that brings into question the safety of the personnel involved or the tunnel itself, the operator will halt the procedure until the issue is resolved.

Post Test Procedure

Upon completion of the test for that time period, the experimenter shall secure all of their equipment prior to leaving the facility.  If additional time is scheduled, determine when the next start time will be by speaking with the operator.  The tunnel operator will secure the tunnel and its auxiliary equipment.

Test Section Modification

There are twelve removable windows in the test section.  They are held in place by a frame providing a viewing area of 24” x 24” but may be replaced with a special window provided by the experimenter as needed to facilitate the model or its control.  No other portion of the test section or tunnel may be modified.