Hybrid modeling bioreactor model

Fuzzy clustering will be used to build a model of the net growth rate as a fimction of the substrate concentration Cg and biomass concentration Cx for the hybrid model of the bioreactor. Assume that an input-output data set has been created using all identification experiments and that the Pl-estimator data are available in the form of measurements. This means that input-output data are available of Cs and Cx and estimates of ju and n . The data set can be presented directly to the clustering algorithm. The initial number of clusters was ten. This number was reduced to three by the merging algorithm. The next step is to project the fuzzy partition matrix onto the cs and cx axis, so that parametric membership fimctions can be determined. This is shown in Fig. 30.9. 

In spite of the success of CFD simulations for the multiphase turbulent fluid flow in stirred-tank bioreactors (see Section 3.4), their application to coupled material balance equations in case of more complicated reaction networks is still limited by the required computing power. Even in case of successful approaches for model reduction, the number of compounds necessary for reliable portrayal of cellular dynamics in response to spatial variation of extracellular compounds may be still too large. An interesting method to overcome these numerical difficulties is the general hybrid multizonal/CFD [27-36], which gave momentum to the application of CFD modeling for bioreactors. 

Bezzo, F., Macchietto, S., and Pantelides, C.C. (2003) General hybrid multizonal/CFD approach for bioreactor modelling. AIChE /, 49, 2133-2148. 

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