The present exemplary embodiment relates to an apparatus associated with aerodynamic and acoustic testing. It finds particular application in conjunction with aerodynamic and acoustic testing of automotive vehicles, and will be described with particular reference thereto. However, it is to be appreciated that the present exemplary embodiment is also amenable to other like applications.
A wind tunnel is often used to test the aerodynamics and the acoustics of an automotive vehicle. A wind tunnel can include a test section housing within which a vehicle to be tested is positioned. An air flow generator such as a fan or blower is used to create an air stream that is directed through a contraction cone and the test section within which the vehicle is positioned. Wind tunnels may be of an open circuit design in which atmospheric air is drawn into the contraction cone and discharged from the diffuser back to the atmosphere. Alternatively, wind tunnels may be designed to recirculate air in a loop or return flow configuration. A wind tunnel also includes instrumentation for measuring the desired information, such as the wind drag created by a vehicle or sounds created as the wind flows over the vehicle.
Wind tunnels are used extensively in the automotive industry for the purpose of determining the effect of air flow on the major system components of a particular vehicle design. For example, testing may involve evaluating the effect of air flow on the vehicles ability to cool the vehicle engine. In this instance, a “climatic” wind tunnel will be used to verify system performance through a range of simulated environmental conditions.
A second category of vehicle evaluations in a wind tunnel involves evaluating or testing the aerodynamic and acoustic effect of the air flow as it flows around the vehicle. For example, the design of windshield wipers, the design of radio antennas, the overall exterior configuration of the vehicle, the effect of open vs. closed windows, etc. are important and regularly evaluated features of the vehicle's design.
Wind tunnels for use in the aerodynamic and acoustic testing of vehicles require careful design to ensure accurate and reproducible simulation of road conditions at the applicable speeds and thus provide reliable design data. To achieve accurate and reliable results and to avoid resonance problems for aerodynamic and acoustic testing, the ability to precisely position a vehicle at a specific location within the test section of the wind tunnel is important. Moreover, by way of example, if a feature on the surface of a vehicle is being modified to evaluate a change in aerodynamic performance, it is important that the vehicle be positioned at the same location within the testing section for each comparative evaluation.
Presently, a vehicle center is positioned at a designated location within the testing section. A vehicle center is identified on the vehicle manually by using measurement squares and a tape measure. The axle centers are projected down to the floor and the distance between the marks is measured. The measurement is divided in half and the calculated sum is indexed from the front axle center and manually marked onto the vehicle to be tested. This methodology has proven to be time consuming and a source of human error.