Abstract:
Calculation of the pressure and flow profiles of a simulation has a major effect on the fidelity,
reliability, robustness and performance of the dynamic simulator. A pressure-flow (P-F) network
consists of several unit operations, connected by streams, where pressure and flow relations must
be calculated. The resistance and volume balance equations produce these P-F relations within the
flowsheet.
This study compared two different solution methods for solving the resultant nonlinear simultaneous
P-F equations, namely the Referred Derivatives method introduced by Thomas in 1997 and the
Newton-Raphson method. In this comparison the advantages and disadvantages of the Referred
Derivative method are provided. This paper also discusses the use of the Referred Derivatives
method in solving flowsheets that include unit operations with holdup.