流れ方向に一様なブレードを有する振動円管内流れにおける微細渦の伝熱促進効果

抄録

An experiment was conducted to investigate on a vibrating pipe flow with streamwisely-uniform blades aiming at the heat transfer enhancement. The experimental apparatus changes the Reynolds number from turbulent to laminar flow as it enters the test section from the entrance section. The test section is oscillated with a frequency of 100 Hz and amplitude of 800 μm. The vibration was generated by means of three piezoelectric actuators. There are a pair of uniform blades facing each other in the flow direction and their angles respect to the direction of vibration θ were varied as 0°and 90°. Particle Image Velocimetry (PIV) measurements were performed on a cross section perpendicular to the flow direction of the test section. As a result, the difference between the periodic and the fine vortices contributed to the increase in the friction drag coefficient.