A semi-implicit conservation element–solution element method for chemical species transport simulation to tapered ducts of internal combustion engine

In order to obtain a reliable numerical solution, with low computational cost, for a differential equation system modelling the unsteady flow with chemical species tracking in tapered ducts of reciprocating internal combustion engine, three characteristics of numerical resolution schemes have to be considered. Firstly, the scheme must show a total variation decreasing (TVD) behavior, also the internal calculations have to be simple and finally, the mass conservation property of each species has to be carried out.With these requirements, a semi-implicit numerical method based in the conservation element–solution element (CE–SE) method is presented. This method helps to obtain a solution where the mass conservation property of each species is improved in relation to the CE–SE method. This last improvement is studied in several real examples with two species in conical ducts.