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Convergence problems using extreme coefficient values like 1e-16 with porous jumpHi fellow CFD users,
I want to model a cylindirical membrane(plenty of membranes) in a cross flow condition, and when I use permemability and C2 coefficients like 2e-16 for face permeability and 3e+12 for C2, problem diverges. I have to use this coefficients because membranes that I want to model, has kind of 0.0001m/s velocity at 100000Pa values. :confused: I am sure these coefficients are the reason behind the divergence. How can I solve this divergence problem ? Thanks |

As you guessed it, are you sure about these coefficients? How did you arrive at these values?
OJ |

hi oj
I arrive this values by plotting xy curve from my experimental data velocity and pressure drop, from the xy polynomial trendline excel generated the y=Ax2+Bx equation that I used to find C2 and alfa permeability coeffitions. I double checked everything that I do in excel. I am sure these coefficients is right. Because these coefficients belongs to a membrane that 0.5micrometer or even lower pore sizes. It has very low permeability compairing to normal filters. |

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