USA flag logo/image

An Official Website of the United States Government

Fan Flow Control for Improved Efficiency and Noise Reduction

Award Information

National Aeronautics and Space Administration
Award ID:
Program Year/Program:
2003 / STTR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
265 Industrial Drive Christiansburg, VA -
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 2
Fiscal Year: 2003
Title: Fan Flow Control for Improved Efficiency and Noise Reduction
Agency: NASA
Contract: NAS3-03077
Award Amount: $499,917.00


Techsburg, Inc. and the Vibrations and Acoustics Laboratory at Virginia Tech (VAL) are proposing an innovative flow control scheme for fan rotors designed to simultaneously increase fan loading and efficiency while reducing fan radiated noise. The technology uses optimized blowing to prevent flow separation and significantly reduce the downstream wake size. A Phase I STTR proved the feasibility of using suction surface blowing jets to produce a sound power reduction on the order of 7dB and a reduction in losses of 60%. This research will combine an optimized flow control design with alternating blowing concepts. Using alternating blowing with an acoustic liner to attenuate the broadband noise will allow us to maximize the noise reduction and minimize the required mass flow. The amount of work produced by a single compression stage is limited by the amount of diffusion that can occur without large-scale flow separation. Viscous losses within the separated region not only result in an efficiency penalty but also create a large wake behind each of the rotor blades that interact with the downstream exit guide vanes and stators. Left untreated, fan exhaust noise from this interaction is the most dominant perceived noise at takeoff and landing. By using flow control to eliminate separation and the rotor wake, both efficiency gains and noise reduction can be achieved.

Principal Investigator:

Sarah Stitzel
Research Engineer

Business Contact:

Stephen Guillot
VP Engineering
Small Business Information at Submission:

Techsburg, Inc.
2901 Prosperity Road Blacksburg, VA 24060

EIN/Tax ID: 311582371
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Research Institution Information:
Virginia Polytechnic Institute
460 Turner Street, Suite 306
Blacksburg, VA 24061
Contact: Ricardo Burdisson
Contact Phone: (540) 231-7355
RI Type: Nonprofit college or university