Pool Boiling Performance of Notched Tubes in Lithium Bromide Solution

Abstract

In the present study, pool boiling heat transfer coefficients in Lithium Bromide ( LiBr ) solution were obtained for smooth, floral, notched fin and notched floral tubes. Test range covered saturation pressure from 7.38 to 101.3 kPa, LiBr concentration from 0% to 50%. Floral tube yielded the highest heat transfer coefficient, and smooth tube yielded the lowest heat transfer coefficient. Effect of notching on heat transfer coefficient was dependent on tube shape. When applied to the smooth tube (notched fin tube), notching increased the heat transfer coefficient. When applied to the floral tube (notched floral tube), on the other hand, notching decreased the heat transfer coefficient. The reason has been attributed to the balance of advantage of added nucleation sites and disadvantage of added flow resistance. Boiling heat transfer correlations were developed which are applicable for saturation pressure from 7.38 to 101.3 kPa and LiBr concentration from 0% to 50%.