MULTICOMPONENT DISTILLATION CALCULATION BY A SUCCESSIVE RELAXATION METHOD USING A FINITE DIFFERENCE APPROXIMATION

摘要

References(15) Cited-By(5) A successive relaxation algorithm is proposed for the solution of multicomponent distillation problems, where the working equation has less round-off error than the Euler equation. By applying the weighting average of forward and backward finite difference to the derivative of liquid mole fraction with respect to time, a numerical integration formula of higher accuracy is obtained. Although the resultant equations have implicit form, they are successfully solved by a successive relaxation algorithm after making reasonable assumptions and combining these equations with the summation equation of liquid compositions. The discussion extends to the method of determining a time increment and a weighting factor based on the results of various numerical examples, so that the proposed algorithm becomes more useful.