i love wind tunnel

What amazing to me is that the reliability of wind tunnel makes it successful in many industries, e.g. aerospace, car design, urban planning, sports suit design... In fact, it is just using a relatively “low-tech” approach in a careful way to produce accurate data. The wind tunnel composed a fan for generating airflow, a test model placed in a fixed area with several instruments to measure the airflow. Of course, there are still many components to make the wind tunnel works. How to visualize the airflow: 1) By smoke blowing over the model to visualize streamline 2) By attaching tuft onto the model to visualize air patterns by their movements 3) By placing color oil or fine powder to show turbulence and flow separation 4) By strobe light with high speed camera to capture turbulence and vortices Picture above: showing tufts attached to a tested aircraft wing: - direction of tuft = direction of airflow - aligned tuft = smooth flow over wing - scattered tuft = separation flow from wing Reference: University of Washington Aeronautical Laboratory, Kirsten Wind Tunnel, www.uwal.org