Paris Air Show

A smarter cool on display here

 - June 14, 2007, 9:27 AM

Technofan is demonstrating its new cooling fans here at the Paris Air Show (Hall 2B Stand D13). The Safran group subsidiary’s design engineers are working to further improve ventilation systems for passenger cabins, avionics bays and wheel brakes. On the new A380 airliner, for instance, a series of innovations is already making cooling fans smarter.

Design trends are toward lighter, more efficient and quieter fans. “Using more composite materials is the way to go to reduce weight,” Jean-Pierre Van Den Bulcke, Technofan’s purchasing manager, told Aviation International News.

Cutting fan noise is relatively complex. In addition to looking for absorbing materials, design engineers are endeavoring to decrease airspeed while maintaining a constant flow, without increasing fan diameter. “We optimize blade profile,” he said.

Enhancing efficiency can be achieved by improving components, digital control and airflow, but it can be tricky. “Efficiency interacts with noise,” Van Den Bulcke explained. Some 50 people work in Technofan’s research and development offices in Toulouse.

Technofan’s products have two roles. The first is to ensure cabin air circulation. The second is to maintain a reasonable temperature for equipment that dissipates heat from electronics or mechanical friction in the aircraft. In helicopters, for example, there is an oil cooling fan for the main gearbox. Some fans have an electric motor, and others are driven directly by the rotor’s shaft.

On commercial airplanes, airlines can choose the brake cooling fan option. Those operations that need a quick turnaround do not allow for the brakes to cool down on their own. Brakes need cooling because there is a maximum allowable temperature at which an aircraft can start taxiing. The fans are all the more useful on carbon brakes, which reach higher temperatures.

The increased use of electronic equipment has driven the need for better cooling in aircraft. For example, over the past few years, DVD player bays have added another application for cooling fans. In total, the installed cooling power on an A380 is 120 kilowatts, Van Den Bulcke said. The aircraft’s 22 fans are used just for cabin equipment and avionics; additional fans are needed for brake cooling (16 optional fans on the A380).

Technofan usually supplies equipment manufacturers. For example, German-based Nord Micro integrates Technofan’s ventilation products into its own pressure control systems. Airbus is the firm’s main end user. On the A380, Technofan has introduced a variable-speed fan that manages the airflow, depending on the cabin’s need.