PROBLEM DEFINITION

This problem examines the flow of a fluid in a microfluidic channel that contains a dissolved substance (nutrient) that diffuses through a membrane and subsequently through a gel that contain suspended cultures. The objective is to study the diffusion of the dissolved substance throughout the membrane-gel system. We are examining non-steady state flow. The geometry and initial/boundary conditions are illustrated below:

EXECUTABLE AND INPUT FILE

Input file (PROB.INP)

Windows 3.x/9x/ME/2000/NT Executable (MICROFL.EXE)

Obtain both files in a compressed package (MICROFL.ZIP)

SAMPLE RESULTS

Concentration contours (movie).

Pictures

Concentration contours at t=50s (generated using CONTOUR):

Concentration contours for the dense phase at t=90s (generated using CONTOUR):

Sample results input file (PROB.INP)

*

* ==[ INPUT FILE FOR MICROFLUIDIC INSTRUMENT SIMULATOR - UNITS IN SI ]===

*

===[ PROBLEM PARAMETRES ]===============================================

Length, and Half of gap between plates, membrane and gel thickness [LENGTH, THICK, THM, THG]

0.1, 6.98e-2, 7e-3, 9e-2

Inlet (max if parabolic) velocity [VEL]

2e-3

Parabolic Inlet velocity profile? [UPARAB]

.TRUE.

Pressure at inlet (Pa) [PRESF]

1.013e5

Inlet concentration of substance (mol/m3) [CIN]

1.0

===[ THERMOPHYSICAL PARAMETERS ]========================================

Fluid Density (kg/m3) [DENI]

1.0

Fluid Viscosity (Pa.s) [VISI]

1e-5

Diffusion coef. of substance in fluid, membrane and gel (m2/s) [DIFFC,DIFMC, DIFGC]

1e-5, 5e-5, 4e-6

===[ GRID PARAMETERS ]==================================================

Number of cells in X-direction [NI]

120

Number of cells in flow, membrane and gel regions [NJF,NJM,NJG]

50, 10, 30

===[ TIME SOLUTION PARAMETERS ]==========================================

.FALSE.

Number of time steps [NT]

100

Duration of time steps (s) [DT]

1

===[ DEPENDENT VARIABLES ]==============================================

Solve for U, V, P equations ?

.FALSE.

Solve for C equation ?

.TRUE.

===[ TERMINATION CRITERIA FOR ITERATIONS ]==============================

Maximum number of iterations per time step  [MAXIT]

100

Maximum acceptable value of residuals  [SORMAX]

1.0E-3

===[ UNDER-RELAXATION ]=================================================

Under-relaxation factor for U(x,y), P equation  [URFU, URFP]

0.5, 0.1

Under-relaxation factor for C equation  [URFC]

1.0

===[ EQUATION SOLVER SELECTION ]========================================

Solver selection for U(x,y), P equation  [ISLVU, ISLVP]

1, 1

Solver selection for C equation  [ISLVC]

1

===[ INPUT-OUTPUT PARAMETERS ]==========================================

I, J index of monitoring location  [IMON, JMON]

5, 5

How many timesteps between output?  [NIOUTP]

1

Name of main output file  [OUTFIL]

RESULT.TXT

Save restart file? [INWRIT]

.T.