Ford Debuts Mobile Aeroacoustic Wind Tunnel

Back in grade school, I built a wind tunnel for the science fair using an old kitchen exhaust fan; my dad even managed to get some dry ice for it (don’t ask me how). It broke in the move from my house to the school, teaching me a valuable lesson about the delicacy of aerodynamic testing instruments.

See Ford's mobile aeroacoustic wind tunnel in action.

But like so many lessons learned in grade school, this one turned out to be wrong, as evidenced by what Ford Motor Company is calling the world’s first fully mobile aeroacoustic wind tunnel, a patent-pending test system for identifying sources of unwanted wind noise in early production vehicles.

Inside Ford’s Mobile Wind Tunnel

The core of the mobile facility is built inside two 53-foot shipping containers modified with aeroacoustic vanes and internal ducting to provide smooth, controlled airflow at the nozzle end of the machine. Two 16-bladed, six-foot-diameter ducted fans—each powered by a 250-horsepower electric motor—deliver a maximum blast of 80-mph wind.

Acoustic baffles provide smooth, controlled airflow.

The machine itself consists of the two containers fastened together side by side on a flat, level tarmac; roll-up doors on the sides of the containers join them together, while doors on the front and back ends constitute the air intake and outlet nozzle.

A third 40-foot container houses a small office, power distribution and controls and is connected to the wind tunnel by heavy power distribution cables weighing approximately 1,080 lbs each.

Despite all this, Ford states that the machine registers only 75 decibels at a distance of six feet from the test area.

Assembly of the mobile wind tunnel at Ford's Flat Rock assembly plant.

According to the company, the entire operation can be broken down within a day, shipped to any North American assembly facility via truck and then reassembled and ready for testing within hours. Once it’s set up, the wind tunnel is capable of 24-hour-a-day operation with just two workers.

Taking Quality Assurance on the Road

Full-sized aerodynamics labs, such as Ford’s primary wind tunnel in Allen Park, MI, are outfitted with extensive measuring and analysis equipment.

With a price tag of approximately USD$50 million, these office-building-sized facilities are designed for aerodynamic and aeroacoustic development work on future models of Ford vehicles. Their high cost and specialized instruments make running time on these machines especially precious.

A Ford employee prepares two Aachen Heads, mobile measuring devices for performing aurally accurate binaural recordings.

The new mobile wind tunnel enables Ford engineers to conduct aeroacoustic testing at a fraction of the cost of a full-size lab by eschewing many of the large and sensitive instruments that are normally required.

Instead, the mobile wind tunnel uses in-cabin sensors like the Aachen HEAD and Ford’s Noise Vision technology to measure wind noise

Ford's Noise Vision creates computerized images of interior noise "hot spots." (Image courtesy of Ford Motor Company.)

Like Ford’s Transportable Environmental Four Posters, having an on-site wind noise facility allows a factory to pull sample vehicles directly from the assembly line and test them immediately rather than shipping them back and forth across the country.

“Now, we’re able to detect even the subtlest noises,” said Ford wind noise core supervisor Bill Gulker. “We can identify an area in need of improvement, have key people gather, communicate quickly and resolve the issue without delay.”

Ford employees demonstrate the company's new mobile wind tunnel.

The new wind tunnel debuted at Ford’s Flat Rock assembly plant in Michigan.

For more stories about Ford’s unique approach quality assurance, click here, here or here.