Effect of fin spacing on heat transfer and pressure drop of two-row corrugated-fin and tube heat exchangers

Experiments using naphthalene sublimation technique were performed to investigate the heat transfer coefficients and friction factors for corrugated-fin and tube heat exchangers with different fin-spacing. The corrugated angle was 15.5 deg., the ratio of fin spacing to the tube diameter varied from 0.189 to 0.379, and the Reynolds number ranged from 400 to 4000. Thermal performance evaluations were carried out for identical pumping power and for identical pressure drop.