Ethirajan RathakrishnanEthirajan Rathakrishnan is professor of Aerospace Engineering at the Indian Institute of Technology Kanpur, India. He is well known internationally for his research in the area of high-speed jets. The limit for the passive control of jets, called theRathakrishnan Limit, is his contribution to the field of jet research, and the concept of breathing blunt nose (BBN), which simultaneously reduces the positive pressure at the nose and increases the low pressure at the base is his contribution to drag reduction at hypersonic speeds. Positioning the twin-vortex Reynolds number at around 5000, by changing the geometry from cylinder, for which the maximum limit for the Reynolds number for positioning the twin vortex was found to be around 160, by von Karman, to flat plate, is his addition to vortex flow theory. Read More Read Less