Page 358 - Modelling in Transport Phenomena A Conceptual Approach

338 CHAPTER 9. STEADY MICROSCOPIC BALANCES WITH GEN.

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Figure 9.4 Flow in a concentric annulus.

The development of the velocity distribution follows the same lines for flow in
a circular tube with the result

(9.1-92)

Integration of Eq. (9.1-92) leads to

In this case, however, r = 0 is not within the flow field. The use of the boundary
conditions
at T=R v,=O (9.1-94)
at T=KR vz=O (9.1-95)

gives the velocity distribution as
(Po - PL) R2 1 - K2
VI = (9.1-96)
4 PL

The use of Eq. (9.1-96) in Eq. (9.1-65) gives the shear stress distribution as