The ViGYAN Low Speed Wind Tunnel facility is housed in the Aero-Fluids Laboratory building located behind ViGYAN offices in the Hampton, Virginia Langley Research and Development Park. The facility, designed and fabricated by ViGYAN personnel, has been in operation since 1988, serving the aerodynamic testing requirements of Government establishments and private companies, in addition to supporting the on-going internal R&D activities of ViGYAN. It has recently undergone a major renovation of its model support, electronics, and data acquisition systems.

The tunnel is a conventional, straight-through, open-return type layout powered by a variable-pitch, multi-blade axial fan located at the exit, providing a precisely controlled airspeed in the test section ranging from 40 to 180 feet per second (or 27 to 122 miles per hour). Ambient air is drawn through an inlet cage lined with densely-woven filter material which also serves to suppress external wind disturbances. The flow passes through a screened honeycomb, a long settling chamber, three woven seamless anti-turbulence screens and finally a 9 to 1 contraction, to be discharged into the test-chamber as a highly uniform jet of rectangular cross-section, 4 feet in width and 3 feet in height. After traversing a 5-foot length the jet is collected by a bell-mouthed diffuser, conveyed through the fan and exhausted to atmosphere. These flow-conditioning measures reduce the turbulence level at the model position to less than 0.1 percent. Sphere tests established the turbulence factor to be under 1.05.

The walk-in test chamber surrounding the test-jet is large enough to accommodate two or three observers during testing, with only ear-protection being required. The free-jet configuration allows instant access to the model and facilitates flow visualization and photography from a variety of viewpoints. Alternate wall configurations (e.g., solid, semi-open, ground board, etc.) can be readily installed for special test requirements.

The model support mechanism allows the model attitude to be varied in the range of -10 to +90 degrees of pitch and -20 to +20 degrees of yaw, accurate to 0.1 degree. It features a closed-loop control system integrated with the data acquisition system for repeatable, efficient conduct of testing operations. A robust instrumentation and control system wiring and instrumentation design and a LabVIEW-based data acquisition system provides measurement and reduction of tunnel conditions, balance loads, and other analog channels. This system is part of a control room network with workstations for customers to view, plot, and process data immediately after each run as well as allow access to previous runs, tests, or customer-supplied comparison data. An improved version of the widely-used Data Analysis System (DAS) software has also been integrated into the system for use as a plotting and analysis tool. Other software such as Kaleidagraph and MS Excel are also available. Full Internet access is available for pre- and post-test data transfer; secured testing arrangements are also available. Data reduction procedures, instrumentation and balance wiring/connectors, and data formats are based on those widely used at LaRC to facilitate easy movement of models, balances, and data between ViGYAN and LaRC. Statistical process control procedures are also in place to monitor data quality in the facility; this information is provided to customers as it is available and analyzed.

A fully-equipped electronics and instrumentation laboratory is also now located in the facility to support testing and special requirements. The adjoining shop supports fabrication of most of the wood, sheet-metal and fiberglass models tested. It also provides model modification services to customer test hardware. ViGYAN also has cooperative arrangements with specialized, high-precision model fabricators in the area as a source of more elaborate test hardware.

The most valuable asset provided by ViGYAN is the support of its skilled and experienced professional and technical staff in its wind tunnel operations. All tests are staffed with a tunnel operator, model technician, and electronics/instrumentation technician. Test engineers are available as needed or required by the customer. In addition to conducting a test program in accordance with customer specifications, consultation and problem-solving services of ViGYAN technologists are also available to enhance the value of aerodynamic projects posed by the users. Users have access to ViGYAN aerodynamicists assigned to tasks at NASA Langley to assist in research projects.

Rental rates for use of the facility is based on hourly occupancy time and the level of technical support requested.

Member of the Subsonic Aerodynamic Testing Association (SATA)   .

Further information regarding test scheduling may be obtained from:

Sudhir C. Mehrotra
Phone: (757) 865-1400, x201
Email:

or

Richard White
Phone: (757) 865-1400, x202
Email: