1000 L/h of oil is heated from 40C to 70 C in a 3 cm ID...

1000 L/h of oil is heated from 40C to 70 C in a 3 cm ID heated copper tube. The inner surface of the tube
is maintained at 100 C. Since the temperature dependencies of the fluid are not given, the properties
will be assumed constant. Assume the viscosity ratio equal one. The following physical property data
are available for the oil. What is the length of the tube?
?? = 2090?/?? ?
? = 880 ??/?3
? = 0.00062 ??/(? ?)
? = 0.173?/? ?
?? = 7.49

Expert Solution

First we have to determine the heat transfer coefficient using the relation of Nusselt number for the tube flow

After that we determine the LMTD of the heat transfer. By determining the heat required to heat the fluid till the required temperature we can equate the following 2 equation.

So

So by equating the two heat equation we determined the length of the tube

So length of tube

L=3.88 meters

Thanks.. Please Thumbs-up!!

Amanda K answered 7 months ago

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