Study of heat transfer coefficient in helical coil
Heat transfer through tubes is well known and studied. Coils are very similar to tubes; expect
that there is additional turbulence created in the liquid by the circular motion of the flow.
Therefore it is usual to apply a correction for the inside coil heat transfer coefficient when
compared to straight pipe. Hewitt et al. (1994) recommends the application of the equation
(21).
d¿
(
h¿ c =hstraight pipe 1+3,5 ·
dc ) (0)
Where,
din inner diameter of the tube, m
dc diameter of the coil, m
The heat transfer coefficient on the outside of the coil depends strongly on the rate of
agitation and the type of agitator used. There are many types of agitators. They can be divided
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