4Reynolds C C O,Evans R L,Andreassi L,et al.The effect ofvarying the injected charge stoichiometry in a partially stratifiedcharge natural gas engine[C].SAE,2005-01-0247.
5Manivannan A,Porai P T,Chandrasekaran S,et al.Lean burnnatural gas spark ignition engine—An overview[C].SAE,2003-01-0638.
6Tunestal P,Christensen M,Einewall P,et al.Hydrogen additionfor improved lean burn capability of slow and fast burningnatural gas combustion chambers[C].SAE,2002-01-2686.
7Jack A S,Gordon J J.Stoichiometric operation of a gas engineutilizing synthesis gas and EGR for nex contral[J].Transactionsof the ASME,2000,122:617-623.
8Cho H M,He B Q.Spark ignition natural gas engines:Areview[J].Energy Conversion and Management,2007,48(2):608-618.
9Patrik E,Per T,Bengt J.Lean burn natural gas operation vs.stoichiometric operation with EGR and a three way catalyst[C].SAE,2005-01-0250.
10Puzinauskas P V,Willson B D,Evans K H.Optimization ofnatural gas combustion in sparklgnited engines throughmanipulation of intake-flow configuration[C].SAE,2000-01-1948.
