Photochemical reactor modeling: a case-study problem. Although radiation is important in heat transfer, an analogous model can be used in the design of photochemical reactors. The modeling of these reactors….
determine whether and to what extent a reactor is backmixed.
The simplified case of Eq. (2.8) with no reaction (Da = 0) is important and provides a very useful experimental method to determine whether and to what extent a reactor is backmixed. The method is known as tracer analysis, also known as stimulus–response experiments. The stimulus represents a change in the inlet conditions, and the change in concentration in the outlet as a function of time is measured and represents the response curve of the system. The exit response can be predicted from the above analysis and matched with the experimental data to test some of the model assumptions, for example, whether the assumption that the system is well mixed holds or not. Two types of tracer injection are common: (i) step injection and (ii) pulse or bolus injection. The outlet responses for these two cases are presented below. This section is also useful for reaction engineering studies, where stimulus–response experiments are common.