TONGJI UNIVERSITY
and four mini-belts to drive the wheel rotation. Both the center belt and the mini-belts have a top speed of 250kph and can move in synchrony with the wind. The five-belt system together with a scoop and the distribution suction for the areas before the moving belts provide a near-realistic representation for the relative motion between the vehicle and the ground. The aerodynamic forces are measured by a sixcomponent balance that has a resolution of 0.005% and 0.007% for drag and lift, respectively.
Balance for AAWT
KEY pARAMETERS FOR CWT Nozzle Dimensions 3.06m x 2.29m/ 3.06m x 4.58m Nozzle Area 7m2/14m2 Nozzle Jet Length: 15m Test Section Dimensions: 20m x 13m x 8m Top Speed 200Kph/100Kph Test Temperature Rang -20°C ~55°C Relative Humidity 5~95%,
Solar simulation systems for CWT
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Furthermore, the CWT is equipped with a chassis dynamometer with movable and drivable rollers for both axles. A solar simulation is installed that has a solar radiation intensity up to 1200W/m2 and has a radiation spectrum representing that from the sunlight. To extend the temperature range, a cold-start chamber is built in the wind tunnel center that can reach a temperature of -40°C. It is noted that the cold-start chamber, the test section and the chassis dynamometer of the CWT were all selected in such a way that both commercial vehicles and passenger vehicles can be tested. Since the wind tunnel was put into operation in the summer of 2009, it has been warmly received by the automakers serving the Chinese market. Up to now, more than 10 companies have used our wind tunnels for their product development. Currently, the AAWT is close to fully booked on a one-shift basis and the CWT, which came into trial operation a few months later, is booked about half of the time. In addition to providing test services to the automakers, the Shanghai Automotive Wind Tunnel Center has been asked to be a key test facility for China’s high-speed train program. In addition to the test facilities, Shanghai Automotive Wind Tunnel Center has a research group focusing on the assessment of the applications of commercial CFD tools for vehicle development. It is believed that these activities, leveraging on the access to the test data on the one side and the research resources of the university on the other, would facilitate the complementarities of the wind tunnel test and the CFD approach to vehicle aerodynamic development. Operating within a university, Shanghai Automotive Wind Tunnel Center has a multi-component mission. While providing test services for our clients in the auto industry is our main task, doing basic research (in vehicle aerodynamics, vehicle aero-acoustics, vehicle thermal management, and CFD) and education are also part of our mission. Fan for CWT
Fan for AAWT
CONTACT Doctor Zhigang Yang, Shanghai Automotive Wind Tunnel Center Email: zhigangyang@tongji.edu.cn WIND TUNNEL INTERNATIONAL | 2010