Abstract
A technique using high-speed infrared thermography was used to measure the spatio-temporal heat transfer to a pulsating flow in a circular pipe. Rectangle-shaped pulsating flow was generated by solenoid valve installed at downstream of test section. The flow was turbulent (Re_D = 13000) at maximum flow rate and early turbulent (Re_D = 3000) at minimum flow rate. At the time of deceleration, complicated heat transfer structure appeared, and which remained with spreading toward streamwise. Thus heat transfer coefficient decreased gradually although flow rate decreased rapidly. On the other hand, at the time of acceleration, heat transfer coefficient was kept low value until flow turbulence was generated although flow rate increased rapidly. Then heat transfer coefficient increased rapidly with growing turbulent.
