On the behaviour of two stirred tanks in series

The multiplicity and stability of steady states of two identical stirred tanks in sequence is considered here, and it is shown how the work of Uppal, Ray and Poore can be extended. Up to seven steady states can arise for a given Damköhler number, but no more than three of these are stable (see the recent paper of Varma [2], (and, more particularly, that of Kubíček et al. [7], the relationship of whose work to this is discussed in the last paragraph below). A test is given for the direction of bifurcation of limit cycles, and a particular example worked out. It is thought that new complexities may arise if the limit cycle in the first reactor acts as a forcing function on the second.