SF-2132 -- Performance of Advanced Heat Transfer Tubes in Refrigerant-Flooded Liquid Coolers

An important class of heat transfer equipment involves boiling of a liquid on the outside surface of metal tubes having an internal flow of a warmer fluid. In the field of air conditioning and refrigeration, this class of equipment is represented by the refrigerant-flooded liquid cooler, which appears most often as a component of centrifugal water chilling systems. In this application, the boiling liquid is Refrigerant-11, while water is passed through the tubes in forced convection.

A new tube has been derived from significant advances made in boiling heat transfer. The new boiling technology achieves a tenfold improvement in boiling heat-transfer coefficients over conventional surfaces.

This paper reports on experimental work with the new boiling surface in pool boiling and on tests of 20-ton flooded chillers equipped with plain and enhanced water-side tubes which have the new boiling surface applied to the outside.