The heat transfer and pressure loss characteristics on a square
channel with two opposite surfaces roughened by high
blockage ratio ribs are measured by systematic experiments.
Reynolds number studied in the channel range from 1400 to
4500. The rib height(e) to hydraulic diameter(D) ratios are 0.2
and 0.33, respectively. The rib spacing(p) to height ratio(p/e)
ranges from 5 to 15. The rib orientations in the opposite
surfaces are symmetric and staggered arrangement. The
experimental results show that (1) the heat transfer coefficients
are increased with the increase of rib height and Reynolds
number, though at the cost of higher pressure losses; (2)when
the rib spacing to height ratio is 10, it keeps a highest heat
transfer coefficient in three kinds of rib spacing to height ratio 5,
10 and 15; (3)the heat transfer coefficient of symmetric
arrangement ribs is higher than the staggered arrangement ribs,
but the pressure losses of symmetric arrangement ribs is larger
than the staggered arrangement ribs.
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.