Wind Tunnel Operation and Testing in the Twenty-First Century: The Case of VTI’s Test Facilities

The concept of the twenty-first-century laboratory emerged at the turn of the century in preparation for future changes in conducting research that will have been brought about by significant technological advances achieved in the previous period. At an extreme end, views were expressed that wind tunnels would have been mostly obsoleted and replaced by computational tools in the first decades of the century. Contrary to expectations, however, there has constantly been rising demand for wind tunnel testing during the last twenty years, but ironically, it has been followed by the overall decline in the number of wind tunnel runs. This apparent contradiction can be explained by the gradual abandoning of conventional wind tunnel test methods with high data volume as a main measure of productivity and transition to the techniques described collectively as the Modern Design of Experiments. Wind tunnel operation and testing in a new era of technology will be explained using the case of VTI’s test facilities. These facilities were built 40 to 70 years ago; some are well beyond their design lifetimes, but they have constantly provided unique testing capabilities in subsonic, transonic, and supersonic speed ranges. The present paper summarizes capability upgrades and embracing the principles of modern design of experiments by the VTI’s wind tunnels, in order to address current and future aerodynamic performance technical challenges.