Determine the heat transfer coefficient for liquid bismuth flowing through an annulus (5-cm-ID, 6.1-cm-OD) at a velocity of 4.5 m/s. The wall temperature of the inner surface is 427°C and the bismuth is at 316°C. It may be assumed that heat losses from the outer surface are negligible.
GIVEN
FIND
The heat transfer coefficient
ASSUMPTIONS
Steady state
Heat losses from outer surfaces are negligible
SKETCH
PROPERTIES AND CONSTANTS
for bismuth at the bulk temperature of 316°C
The hydraulic diameter for the annual is given by
The Reynolds number based on the hydraulic diameter is
For liquid metals, the Nusselt number is given by
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