Numerical Simulation of Turbulent Reactive Jet in Liquid by the Semi-empirical PDF Method

抄録

Turbulent reactive jet in liquid has been simulated by the “semi-empirical” Lagrangian probability density function (PDF) method, by which the velocity field consistent to the specified moments of the Eulerian PDF of velocity can be reproduced. The chemical reaction treated in this study is a second-order irreversible reaction, R + B → S, where a solution of species R is ejected from the nozzle into the main stream that includes species B. The Lagrangian velocities of the stochastic particles are modeled by a generalized Langevin equation in the cylindrical coordinate system. This model is constructed to satisfy the consistency condition of a velocity field and the thermodynamic constraint. For the molecular mixing of reactive scalar concentrations, the most fundamental IEM (interaction by exchange with the mean) was adopted. The simulation results are compared with the experimental data. It is found that the velocity field simulated by the present model satisfies the consistency condition up to the second-order moment and the thermodynamic constraint. The simulated reactive scalar concentration field shows almost the same distribution, on the whole, as the experimental data. Therefore, the models used in this study are useful for a turbulent reactive jet.