The current wind sensors used at remote KSC locations for wind speed detection are deficient in two main areas. First, rotating cup-and-vane-type anemometers have a high maintainability because of the wear and tear of their moving components. Second, there is a high degree of failure associated with such systems because of damage from extreme wind conditions. A key reference is Hurricane Andrew in 1993, when no ground-based wind sensors survived the path of the storm. Hence, there are no verifiable measurements of the highest winds generated by Andrew.

The three-dimensional (3-D) Venturi wind sensor was developed to provide measurements of extreme winds at various locations around KSC. The 3-D Venturi wind sensor is a device for the measurement of wind speed through the use of pressure measurements across a known shape. The basic form is that of a typical streamlined venturi profile (a double-inflection curve) revolved 360 degrees about an axis passing vertically through the center of the profile. The profile has a series of instrumented ports located near the center and periphery to allow for pressure measurements along the surface. The wind speed is calculated by applying Bernoulli’s law to the pressure change created between the ports. (Eqn. ). Wind direction is derived from the pressure profile distributed over the surface. In addition, temperature and relative humidity measurements are incorporated into the design.

A conceptual approach was devised to create a surface wind profile (wind velocity and direction) sensor by combining pressure measurements and smart software algorithms and incorporating the knowledge developed using Computational Fluid Dynamics (CFD) simulation.

The result is a design that incorporates many beneficial qualities that make the 3-D Venturi an attractive alternative to the current equipment. The 3-D Venturi has a relatively small profile and no moving parts. It has a fast response, wide dynamic range, and short recovery time and incorporates both speed and directionality of wind, an inherent advantage over cup-and-vane anemometers. Furthermore, the design will be capable of autonomously acquiring and storing data during a storm for further analysis.

Key milestones:

• Validate design at extreme wind velocities to 300 mph.
• Conceptualize and integrate methodology for wind direction determination.
• Optimize port locations to achieve best sensitivity and dynamic response.
• Optimize design to provide a remote, stand-alone system capable of autonomously acquiring, recording, and storing storm information.
• Ruggedize the design for field deployment.
• Field-deploy and test system.

Key accomplishments:

• 2000: First prototype built and tested in low-speed wind of approximately 127 miles per hour (mph). Validation of design concept.
• 2001/2002: Modeling, analysis, and simulation of design at high wind velocities using CFD software.

3-D Venturi Prototype at Embry-Riddle Aeronautical University

Contacts: J.A. Zysko (Jan.Zysko-1@ksc.nasa.gov), YA-C3-F, (321) 867-7051; and J.M. Perotti, YA-D5-E, (321) 867-6746
Participating Organization: Dynacs Inc. (J.J. Randazzo, A.J. Eckhoff, and N.N. Blalock)