New Light on Some Old Problems: Revisiting the Stefan Tube

New Light on Some Old Problems: Revisiting the Stefan Tube, Graham's Law, and the ... By continuing to use the site, you are accepting our use of cook...
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Ind. Eng. Chem. Res. 2000, 39, 243

243

Volume 38, Number 6 A Strategy for Detection of Gross Errors in Nonlinear Processes. T. Renganathan and Shankar Narasimhan* Page 2394. The correct form of eq 19 is as follows: i Tk+1 ) Max T k+1

(19)

i

IE991083Z 10.1021/ie991083z Published on Web 01/04/2000

Volume 36, Number 3 New Light on Some Old Problems: Revisiting the Stefan Tube, Graham’s Law, and the Bosanquet Equation. Piet J. A. M. Kerkhof Page 916. Equations 1 and 2 should read:

|

∂〈Pi〉 ∂z

n

) RT

T

|

∂〈Pi〉 ∂z

∑ j)1

Φij(xi〈Njz〉 - xj〈Niz〉 ^ij n

) RT

T

∑ j)1

(xi〈Njz〉 - xj〈Niz〉 ^ij

Equation 6 should read:

|〈Ngz〉| )

(

- fimRT〈Niz〉 (1) - fimRT〈Niz〉 (2)

)

r02 Pg0 + PgL 1 Pg0 - PgL + DKg 8η 2 RT L

(6)

The foregoing errors have no consequence for the rest of the material. Page 920. In section 5 I made a mistake in the derivation of eq 34, and as a consequence the flux ratio at low Knudsen numbers NKn would be predicted wrong from this equation, and as a consequence the following statement is wrong: “It is remarkable [...] reported before.” The correct version of eq 34 should read:

〈N1z〉 〈N2z〉

≈-

η20 x1 + x2ξ12 κ2 )- 0 κ1 η x1ξ21 + x2

(34)

1

with the Wilke parameters ξij given by eq 11. For components which differ considerably in molecular mass but only slightly in pure-component dynamic viscosity, ξij lead to a deviation from unity in the flux ratio. Numerical inspection shows that the ratio of the fluxes in the high-pressure limit, as given by the revised eq 34, is not equal to that given by Graham’s law, but the deviation is on the order of 10%, as can also be read from Figure 10. As a consequence also my statement at the end of the same section is wrong: “From the analysis...H2O-N2.” IE9910625 10.1021/ie9910625 Published on Web 12/03/1999