Abstract
Heat transfer, pressure drop, and flow visualization experiments were performed for a tube-bank-type crossflow heat exchanger situated downstream of a right-angle bend. The heat exchanger was housed in a duct of square cross section, and the L-shaped duct which delivered the airflow to the tube bank inlet was of identical cross section. Two geometrical parameters were varied during the course of the experiments: (1) the distance between the bend and the tube bank inlet and (2) the orientation of the plane of the bend with respect to the axes of the tubes in the bank (either parallel or perpendicular to the axes). The Reynolds number was varied over nearly an order of magnitude. For each geometry and Reynolds number, per-tube heat transfer coefficients were determined at each relevant tube site in the array. It was found that the presence of the right-angle bend did not have a major effect on the heat transfer characteristics of the tube bank. Bend-related enhancements in the 10-15% range were encountered at individual tubes in the initial rows, but the rowaverage enhancements were smaller. Intra-row nonuniformities occurred for the perpendicular orientation but not for the parallel orientation. The system pressure drop (from delivery duct inlet to tube bank exit) was even less sensitive to the geometrical parameters than the per-tube heat transfer.
Original language | English (US) |
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Pages (from-to) | 1649-1657 |
Number of pages | 9 |
Journal | International Journal of Heat and Mass Transfer |
Volume | 27 |
Issue number | 9 |
DOIs | |
State | Published - 1984 |