Application of interval Newton's method to chemical engineering problems

The interval Newton's method in conjunction with generalized bisection, as implemented in the public domain mftware program INTBIS by Kearfott and Novoa, is a method of miring single and simultaneous nonlinear equatiom. In this paper, this method is used m solve 15 test problems from different chemical engineering application areas, and an ill-scaled tramcendentai equation. The interval method as implemented in INTBIS is capable of finding all the real roots of an equation within a ~:cified domain. The complex roots were found by representing every complex variable z = z + iy by two real-valued variald~ z and y. For polynomial et~atiom, the computer time for [NTBIS is compared to that of the parallel-path continuation method of Morgan as implemented in the puhtic domain software program CONSOL8. Unlike the parallel-path continuation method, that can fmd all real and complex roots without specifying an initial domain, INTBIS reqaires the apriori spedfication of an initial domain. The effect of the size of the initial domain on the computer time for INTBIS was studied for a ~ t of multi-variable polynomial equations.