More information on the consecutive reaction in a batch STR and in a CSTR

Run the simulation 'des_cstr_consec.vee'. Here you can draw the marker in the plot to the maximum of component B and read the concentration B_max as well as Tau_max after stopping the simulation (marker data is visualized on the bottom of the panel!). These values can be used for a comparison with calculated values and stand for the Maximum of Product B reachable in 'not back-mixed' reactors ( and you know: in the totally back-mixed CSTR you are 'not better', - why ? You need a qualitative explanation?) I have delivered the simulation of the reaction in a CSTR, now you can try it also 'at the simulation'. But You should be able to give the proof by deriving formulas and then compare it with the simulation results, see further details ( german speaking students find it in the book of Jens Hagen, Chemische Reaktionstechnik)! When carrying out the simulation you have to realize that you can't change the zero input concentrations of component B and C here ( and that is better, because it would get too 'chaotic' then). You have to wait till the 'vessel' has reached stationary values ( how many Taus are that, mainly for component C, do you know the rule?). When you have seen the 'elementary things', play a bit with changing the input concentration of component A ! Now you should have realized the difference between a stationary CSTR and one in the start-up- , shutdown- or disturbed phase. Do you for instance realize that you can be lazy in computing when neglecting the transition state of a CSTR disturbed for a short time, - you could alternatively calculate the new stationary state and wait for n Taus. If you are fast at computing, you can get new data for a 'feed-forward' controller much faster than the n Taus of the system, that means that this controller can react faster than a feed-back type! Did you also realize that, in spite of 'being better' in the 'not-back-mixed' reactor types batch STR and TFR, you have here the problem of a concentration level optimization, - you can not, as in the case of simple reactions, choose a very high conversion, on the contrary - you have to choose a very special reaction time = conversion = space time in your reactor!!!!

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