ISSN Online: 2377-424X
ISBN Print: 0-89116-299-2
International Heat Transfer Conference 7
HEAT TRANSFER COEFFICIENT BY WATER JETS IMPINGING ON A HOT SURFACE
Abstrakt
This paper deals with experimental determination
of the heat transfer coefficient of water
jets impinging perpendicularly on a hot surface.
In the experiments, a method involving a transient heat flow through the specimen is applied, and the heat transfer coefficient is evaluated from the respons of a thermocouple beneath the surface of specimen. Heat transfer coefficient is determined for single jet, for arrays of jets, for several configuration of jet versus surface, and for different impulses of the jet.
The heat transfer coefficient for single jet is shown to increase monotonously with increasing surface temperature. The heat transfer coefficient for arrays of jets is shown to have an optimum value at a certain velocity of jets. It is explained by the interference of spouted droplets with adjacent jets which thereby are losing impulse pressure on the surface.
In the experiments, a method involving a transient heat flow through the specimen is applied, and the heat transfer coefficient is evaluated from the respons of a thermocouple beneath the surface of specimen. Heat transfer coefficient is determined for single jet, for arrays of jets, for several configuration of jet versus surface, and for different impulses of the jet.
The heat transfer coefficient for single jet is shown to increase monotonously with increasing surface temperature. The heat transfer coefficient for arrays of jets is shown to have an optimum value at a certain velocity of jets. It is explained by the interference of spouted droplets with adjacent jets which thereby are losing impulse pressure on the surface.