The simulation of chemical reactions in a turbulent fluid is very important for industrial applications. In particular, models which demand only moderate computational times while still taking into account the inhomogeneity of the reactor are of practical interest. An approach is presented here which applies a simulation of the turbulent now field in describing the transport production and dissipation of a non-reactive tracer. Two modelling approaches (the turbulent mixer model of Baldyga and the spectral relaxation model of Fox) are compared with experimental data of a laboratory tubular jet reactor. The turbulent flow field was obtained from a computational fluid dynamics code using the k-epsilon model. The closure approximation of Baldyga, which is based on a prescribed form of the probability density function is applied in modelling chemical reactions. Simulations were performed for a series-parallel reaction.