CFX 코드를 사용한 비정상 DC 전기삼투 유동 해석기법 개발

In this study, we couple a commercial code, ANSYS CFX and Fortran codes for solving electro-osmotic flows around a pair of electrodes receiving DC potentials attached to the top and bottom walls of a rectangular domain. Up to now, no work has been presented in the literature which obtained the solutions of the electro-osmotic-flow problems by using the CFX. Difficulties in this techniques are: Firstly, the ion transport equations (i.e., Nernst-Planck equations) must be solved by using the general transport equation provided by CFX, but in most often there is numerical instability in treating the source terms. Secondly, to calculate the source term we need to evaluate the electric field which must be obtained from a separate Fortran code in terms of the potential which is given from the solution of the Poisson equation. In this case, care must be given to the computer-memory problem. In this study, we develop a module of Fortran programs which are used in solving the ion transport problem in coupling with the CFX. We will present how the developed code is applied to solving the dc electro-osmotic problem within a simple geometry. We also address various problems encountered during the development process and explain how such problems are tackled.