Example computation of concentration and temperature rise

The evolution in time of the concentration of the species A and of the temperature rise AT, for the example data in Table 4.1, is shown in Fig. 4.1. The behaviour is in many ways similar to that of the isothermal cubic autocatalysis model of the previous chapters. The concentration of the precursor P decreases exponentially throughout the reaction. The temperature excess jumps rapidly to approximately 80 K, from which value it begins to decay approximately exponentially. At the same time, the concentration of the intermediate A rises relatively slowly to values of the order of 10 i mol dm-3. After approximately 15 s, the concentration of A and the 

Dimensionless form of mass- and energy-balance equations 

In the previous chapter we found that the equations could be written in particularly economical forms and in such a way that large or small quantities could be easily recognized, by adopting a number of dimensionless 

For the moment let us assume that we shall be able to find a natural measure of concentration cref that will play a similar role to the quotient (k2/kl)il2 in the previous chapter. We will define cref later, and we will then write 

The temperature rise, AT, may be made dimensionless by borrowing from thermal explosion theory. There the natural dimensionless temperature rise 6 is defined by 

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