ライブラリ登録: Guest

ISSN Online: 2377-424X

International Heat Transfer Conference 12
August, 18-23, 2002, Grenoble, France

Experiments on convective heat transfer of air-flows at low Reynolds Number through wavy and grooved channels

Get access (open in a dialog) DOI: 10.1615/IHTC12.5160
6 pages

要約

This paper presents experimental data on heat transfer coefficients and pressure drops of air-flows at Reynolds number ranging between 500 and 7000 inside a wavy channel and two grooved channels. Data for a plain channel are also reported for comparison. All channels have a rectangular cross-section with ribs or grooves perpendicular to the streamwise direction; the channel height is 15 or 18 mm. The wavy channel is characterized by triangular cross-section ribs spaced by flat strips, which alternate staggered on the lower and upper walls; the other two channels have grooves only on the lower wall with an aspect ratio of 1:1 and 2:1, respectively. Local heat transfer characteristics are investigated by non-intrusive measurements of velocity and temperature fields by means of LDV and holographic interferometry; data on average coefficients and pressure drops are also reported. Data for Re≤2000 are compared to the results of direct numerical simulations obtained by means of a CFD commercial code. For the wavy channel, the heat transfer enhancement is quite small (20%) within laminar regime while it becomes a quickly increasing function of Re for values greater than 1300; however, pressure drops also start to steeply increase. The grooved channels are characterized by a poor enhancement (30%) but without significant penalization in pressure drops.