A few days ago, BMW officially opened its new Aeroacoustics and Electric Drive Center (AEC). It is the largest and quietest vertical acoustic wind tunnel in the world, located in the Research and Innovation Center (FIZ).

The building has a three-meter-thick floor plate and is soundproofed from ambient noise. It consists of two separate sections, the first of which is a multi-purpose area with workshop, test and measurement equipment, while the second is a wind tunnel that is almost 100 meters long, 45 meters high and 25 meters wide.

The wind tunnel is designed as a semi-free field acoustic space. This means that, apart from the soundproofed floor, there are no sound reflections. This allows for a realistic simulation of the situation on the road. The frequency range for semi-free field conditions of 30 Hz is unique for this vehicle wind tunnel and covers the entire sound spectrum. Thanks to 216 microphones, it is possible to determine the precise localization of background noise with great precision.

It should also be noted that the facility is equipped with a 4.5 MW fan, which can deliver up to 100,000 m³ per minute at a speed of 250 km/h. In addition, the wind tunnel is equipped with a laser vibrometry system for non-contact measurement of mechanical vibrations of the entire surface of the vehicle.

Source: BMW