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Water at a mean velocity of 0.2 m/s is heated from 20 to 40°C by passing...

Water at a mean velocity of 0.2 m/s is heated from 20 to 40°C by passing it through a 0.5-cm-ID tube. The 2
surface is heated with a uniform heat flux of 6000 W/m . Find the following: a) The length required to heat the water to a given temperature.,b) the surface temperature at the inlet of the tube. Given that the following information: The physical properties of liquid at 30 °C:
?? =4182?⁄??.°?,?=0.6405?⁄?.°?,??=3.57,?=0.5537×10−6?2⁄?,?=988??⁄?3

Solutions

Expert Solution

We can find out the length of the tube by balancing the energy.

And by using the equation of nusselt number we can determine the convection heat transfer coefficient.


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