The modelling of multilayer reactive injection moulding is studied. Af
ter presenting the equations describing the process, two important asp
ects are dealt with in more detail. These are particle tracking and th
e modelling of the flow front. First results demonstrate the possibili
ties of the modelling and show satisfactory agreement between predicti
ons of numerical simulations and experimental results, concerning part
icle tracking in the whole flow domain and the break-through of layers
in sequential two component moulding.