In October 1985, a new wind tunnel was completed and put into operation at the Nissan Technical Center. This paper describes its main specifications and performance features, and gives results of a number of experiments using the new facility.
It is a closed-circuit wind tunnel of the so-called Göttingen type, with a semi-open test section. The test section is equipped with two different nozzles, which are used interchangeably depending on the type of testing being carried out. The larger nozzle has a maximum wind velocity of 190 kmh, and a cross-section 4 m high by 7 m wide. The other is 3 m high by 5 m wide and has a maximum wind velocity of 270 kmh. All of the testing equipment in the tunnel, including the axial-flow fan, six-component aerodynamic balance, and traverse system, are operated automatically by a control system made up of several computers linked together.
The most notable feature of this wind tunnel is the large reduction that has been made in background noise. The walls and ceiling inside the tunnel have been covered entirely with sound-absorbing material, and the chamber surrounding the test section has been made semi-anechoic. As a result it is possible to measure and analyze even very slight wind noise generated by a vehicle, across the whole range from low to high frequencies.