The steam generator design procedure outlined in Section 5 is based on the effectiveness. In this…

The steam generator design procedure outlined in Section 5
is based on the effectiveness. In this problem we want to design the steam
generator by using a differential approach. [Hint: Writing a steady state
energy balance in the axial and transverse directions for an element of length
alongside the tubes gives:

where subscripts i, s, and o stand for tube
side, tube, and tube-bundle-side. Use Equation IVa.6.8-2 to relate the various
thermal resistances, as shown below, to the overall heat transfer coefficient.

Equation IVa.6.8-2

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The steam generator design procedure outlined in Section 5
is based on the effectiveness. In this problem we want to design the steam
generator by using a differential approach. [Hint: Writing a steady state
energy balance in the axial and transverse directions for an element of length
alongside the tubes gives:

where subscripts i, s, and o stand for tube
side, tube, and tube-bundle-side. Use Equation IVa.6.8-2 to relate the various
thermal resistances, as shown below, to the overall heat transfer coefficient.

Equation IVa.6.8-2

Substitute for Ti – To
from Equation 2 and integrate from inlet (I) to exit (E) to
obtain:

To find the required tube surface area, you need to find the
heat fluxes at the inlet and exit of the tubes. These are determined from
Equation 2 by using the NewtonRaphson method].

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