ISSN Online: 2377-424X
International Heat Transfer Conference 12
Time- and Space-Averaged Convective Heat Transfer from the Surface of a Circular Cylinder in an Oscillating Flow
Аннотация
The heat transfer characteristics of a circular cylinder in a sinusoidally oscillating flow and its flow pattern were experimentally studied, which represents the most fundamental component of wire-mesh type matrix for a regenerator. A transient method and a smoke flow visualization technique were employed to determine the time- and space-averaged heat transfer coefficient of the cylinder and to observe the flow characteristics, respectively. Experiments were conducted varying the Keulegan-Carpenter number, KC, and oscillating Reynolds number, Reos, in the ranges of 62.8<KC<188.5 and 55<Reos<812. The results show that the time- and space-averaged heat transfer coefficients increase with the oscillating amplitude and the oscillating
frequency. The relation between Nusselt number and Reos for the oscillating flow cases coincides with that for a circular cylinder in uniform flow cases at Reos>120, even though the flow structures are totally different each other as confirmed by flow visualization. Nu can be corrected against the oscillating Reynolds number and Grashof number.