A Method for Improving Heat Transfer to a Boiling Fluid

A simple design of fins for boiling heat transfer

“…Since the temperature at the junction of two segments is known, the segment length and heat transfer rate in the k-section can be calculated from Eqs. (4), (5), (8) and (11). In case the fin tip is subject to transition boiling, Eq.…”

“…To make the heat exchanger more compact and practical, many investigators [11][12][13] showed that a higher heat transfer rate may be achieved by applying a prescribed thickness of insulation to a smaller fin at high operating temperatures. As for the optimization of fins, Haley and Westwater [5] proposed a turnip-shape fin with minimum volume for boiling heat transfer.…”

Cooling dynamics in thermal quenching for cryopreservation

“…Previous studies on the cool down of coated metals in liquid nitrogen [40][41][42][43][44] suspect an early transition from film to nucleate boiling regime caused by the formation of cold spots at the liquid-coating interface. However, no microscale heat transfer studies are reported to support this claim.…”

“…It can be seen that the surface heat flux is proportional to the thermal effusivity value, whereas thermal penetration depth is proportional to the thermal diffusivity value. Several researchers [39][40][41][42][43][44][49][50][51] have reported on obtaining a higher heat flux by coating the metals using materials with low thermal effusivity. The higher heat flux is obtained by an early transition to the nucleate boiling regime suspected due to a large temperature drop at the coating surface in contact with the liquid.…”

Peak heat flux in nucleate boiling heat transfer

“…This would make the attainment of peak heat flux independent of source temperature for temperature-input systems and transient upsets in heat-input systems. A recent demonstration of this principle (insulation of the heating surface in order to increase the boiling heat transfer coefficient and thus the total heat flux) involved coating the boiling surface with such heat insulators as varnish, asbestos, and vaseline (11). A series of unsteadystate quenching experiments were made using, liquid nitrogen as the cooling fluid.…”