CLOSED CIRCUIT WIND TUNNELS

DESCRIPTION

AEROLAB specializes in custom-made closed circuit wind tunnels (CCT).

The use of steel for construction offers complete design freedom to meet your unique specifications and needs, such as low overhead clearance or building support columns.

Most AEROLAB CCT designs are traditional single-return, horizontally arranged circuits. However, any configuration is possible.

As with all AEROLAB wind tunnels, exceptionally steady test section flow with close uniformity of velocity is standard. Turbulence level is typically below 0.10 percent throughout the full tunnel speed range.

Contact AEROLAB with your ideas (size, speed, shape) for a free, custom-made quote.

Advantages of Closed Circuit Tunnels with comparison to Open Circuit Tunnels

·         Power requirement for a given speed is lower.

·         Particulate matter can be contained within the circuit.

·         Noise is significantly lower.

·         Laboratory air movement (air vents, doors, windows, etc.) does not affect wind tunnel flow.

·         Air entering the test section is free of laboratory dust.

·         Fan blades are not as vulnerable to damage from model failure.

Disadvantages of Closed Circuit Tunnels with comparison to Open Circuit Tunnels

·         Cost is generally three times greater for a given test section size.

·         Air supply is recycled which can be prohibitive when working with combustion engines.

·         Footprint is much larger and requires more overall space.

·         Increasing air temperature can become an issue during prolonged use.

Performance Specifications

·         Airspeed Range : customer-defined

·         Turbulence Level: typically < 0.1%

Contraction

Contraction ratio (inlet-to-outlet area ratio) is a major driver in the overall size and complexity of a closed circuit tunnel. Power requirements, accordingly, follow.

AEROLAB uses either a fifth, or, ninth-order polynomial to define a smooth transition between the settling chamber (contraction inlet) and the test section entrance.