Method of Wang and Oleson

The Newton-Raphson technique is also modified in this method. A damping factor a, between zero and one, is applied to the corrections as above. The way a is calculated, however, is different from the Naphtali-Sandholm method. 

This technique, combined with Fenske shortcut calculations for generating initial estimates of temperature profiles and stage liquid or vapor flow rates, is a robust method that can solve a large percentage of different types of separation processes. The algorithm also has provision for handling inequality specifications (Brannock et al., 1977). For each inequality specification, an alternate equality specification is required to ensure a unique solution. In this manner, the so-called over-constrained problems may be solved since inequality specifications are not subject to degrees of freedom restrictions. 

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