Xk 1 Xk i AXk

where t is such that 0 < t < 1. t is the factor that ensures progress toward the solution of the system at equations of each iteration.

Inside-out algorithm In the Naphtali-Sandholm method, the temperatures and component flowrates are the primary solution variables (see eqn [13]) and

Table 2 MEH equations for method of Naphtali and Sandholm

Relationship

Equation

Table 2 MEH equations for method of Naphtali and Sandholm

Relationship

Equation

Component flow rates

Vni

= yn,

i ■ Vn

and side streams

lnj-

~ Xn,i

■ Ln

fnj-

= Zni

■ F,

s, =

-- Un/Ln

Sn-

= W

/Vn

M

Mni

i ■ (1

+ s,) + Vni ■ (1

+ Sn)

-

" In + 1,

i- vn- 1i fni

E

Eni

i ni

( S Vn,kfS kk) -

- Vni " 0

H

\k k )

Hn-

= hn

■ (1 +s) ■ S Ini i

+

Hn ■

(1 + S,) ■ S Vni

-

hn + 1

■ S k + 1ii- Hn-i

1 ■ S Vn-1i i

-

H F, ■

S fni- Qn " 0 i

are used to generate the K values and enthalpies from complex correlations. Hence, such a method updates the primary variables in an outer loop, with the K values and enthalpies updated in an inner loop whenever the primary variables change.

In inside-out algorithms, the previous situation is reversed. These methods use complex K values and enthalpy correlations to generate parameters for simple K values and enthalpy models. Hence, these parameters become the variables for the outside loop. The inside loop then consists of the MESH equations. In every step through the outside loop, the simple K values and enthalpy models are updated by using the MESH variables from the inside loop. This sets up the next pass through the inside loop. The book by Kister (1992) provides detailed guidelines for the use of the various inside-out methods.

Solar Panel Basics

Solar Panel Basics

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