Two-phase unsteady-state model for reacting system
 

Dear all,

I want to set up a unsteady reactor model for simulating a bubble column slurry reactor with complex chemistry reactions. In my model, the material balance of each species for two phases (gas and liquid phases) is described using axial convection-diffusion model (namely 1D in our case).

In order to make the equations to be closed, there still needs two additional equtions to calculate the superficial velocities for gas phase and liquid phase (UgCi or UlCi as in convection terms).

I have used the method of summing the material equations of all species and then neglecting the dynamic accumulation term so as to calculate the superficial velocity for gas and liquid streams. And then the orthogonal collocation (OC)method is used to solve the resulting PDEs equations. But I found that with the time evolution the liquid velocity will become a negative value and make the simulation fail.

Now I'd like to Finite Volume Method (FVM) because it is better than OC method in keeping the material conservation. And the Cell-based and Node-centered descretization pattern has been finished. Now I am organizing Fortran program by FVM for this model.

Here I want to forward two questions:

(1) I wonder whether my treatment of computing the superficial velocities is resonable.

(2) How can I get the literature about the two-phase CFD simulation for chemical reaction systems?

Thanks in advances.