The scope of the paper is the analysis of the possibility of increasing conversion in different types of systems based on continuous stirred tank reactors. A numerical model of the cascade with constant direction of material flow is tested, a model of changes of direction flow and a relaxation model. The analysis is conducted by means of parametric continuation method and numerical simulation, with the designation of bifurcation diagrams and time series. An essential impact of the relaxation method on the increase of the conversion degree is indicated. (C) 2011 Elsevier Ltd. All rights reserved.