Solar Simulation in France: Cloud and Tunnel Simulation for Vehicle Testing

Vehicle testing requires consideration of both the intensity of solar radiation and how it changes over time. Rapid transitions between sunlight and shade, such as when driving through a tunnel, place particular demands on air conditioning, thermal management and display systems.

For these testing applications, BF Engineering has installed a solar simulation system with cloud and tunnel simulation in France. The system combines 28 HMI luminaires, each rated at 2.5 kW, with a dedicated Cloud & Tunnel Shutter System.

The shutter system enables rapid transitions between full irradiation and shading under controlled and repeatable conditions. For example, it can reproduce a vehicle moving from direct sunlight into a tunnel and returning to sunlight a few seconds later. The applied radiant load changes without the vehicle or ambient temperature immediately changing to the same extent.

The system achieves an irradiance of up to 1,200 W/m² across an irradiation area of 5.6 × 2.5 m. Airflow speeds of up to 150 km/h are also possible during solar simulation testing. This combination provides realistic testing conditions for complete vehicles.

Applications include testing heating, ventilation and air conditioning systems (HVAC), evaluating thermal management and investigating cabin comfort. Head-up displays (HUDs) can also be tested under rapidly changing light conditions.

With this installation, BF Engineering expands vehicle testing capabilities through precisely controlled transitions between solar irradiation and shading. This allows the effects of changing radiation and light conditions on vehicle systems to be investigated under repeatable conditions.