EGR AND AIR INTAKE MIXING STRATEGY FOR INTERNAL COMBUSTION ENGINES TO CONTROL CYLINDER-TO-CYLINDER AND CYCLE-TO-CYCLE VARIATIONS

摘要

The disadvantage of several combustion technologies such as HCCI, PCCI, CAI, ATAC, UNIBUS, etc to reduce NOx and Soot emissions simultaneously from internal combustion engines with different fuels is lack of direct control on combustion i.e. start of combustion and heat release. These combustion technologies, one way of controlling combustion phasing is by induction of EGR into the cylinder along with fresh air and the start of combustion is depending on amount of EGR. With high EGRs the cylinder-to-cylinder and cycle-to-cycle variations are often due to uneven mixing of EGR and fresh air in the manifold and these variations also affect the performance of engine. Whereas, this invention improves the uniform mixing of fresh air and EGR in the manifold with minimum variations in EGR fractions at each outlet of the manifold. It reflects minimum variations of cylinder-to-cylinder and cycle-to-cycle as well as improvement in engine perforrnance. Further this invention as explained with the help of Figure la shows the cross sectional view of venturi. Figure lb shows volute chamber for circulation of EGR. Figure 2a shows flange attached to the volute chamber. Figure 2b shows the assembly of venturi, volute chamber and EGR entry passage and Figure 3a shows the assembly drawing of EGR mixing components. Figure 3b shows the orientation of EGR passage from volute chamber into the fresh air stream.