Simulation And Experimental Research On The Performance Of Integrated Aftertreatment Device For Marine Diesel Engine

With the increase of ship’s in possession and engine power in recent years,the environmental pollution caused by ship emission pollutants is more and more serious.Given this,Countries and organizations around the world have formulated much more stringenter regulations on pollutant emission control of marine diesel engines,which limitted the emission of various pollutants.The space condition of marine engine room is the main limiting factor restricting the synergy of multiple exhaust aftertreatment technology,therefore,the integrated emission control technology for multiple pollutants is an urgent problem to be solved.The main contents of this thesis were as follows:The simplified model of DOC+CDPF reactor was perform 3D and 1D simulating calculation through AVL fire and AVL boost software.Through three-dimensional simulating calculation,the flow field in the reactor and the particle distribution state before the catalyst were studied.The catalytic oxidation reaction of DOC,the pressure loss of the CDPF carrier and its continuous regeneration reaction were studied by the one-dimensional simulating calculation.And both of which were Compared and verified with the experimental results.The SCR aftertreatment system was perform 3D and 1D simulating calculation through AVL fire and AVL boost software.The flow field inside the reactor and the distribution of the reducing agent before the catalyst were analyzed through three-dimensional simulating calculation,and the selective catalytic reduction reaction of the SCR catalyst was studied through one-dimensional simulation calculation.both of which were Compared and verified with the experimental results.By analyzing the feasibility of experiment,adopt DOC+CDPF+SCR as the technical route of diesel engine emission aftertreatment,A bench experiment was performed connecting the reactors used previously in series.One-dimensional simulating calculation was carried out to study the differences between the selective catalytic reduction reaction on the SCR catalyst and the above,then Compared and verified with the experimental results.Secondly,the SCRF catalyst was studied by three-dimensional and one-dimensional simulating calculation,the flow field,reducing agent distribution,particle distribution and selective catalytic reduction reaction state were analyzed.Its advantages and disadvantages were analyzed and compared with the experimental results.Final,the integrated design of the DOC、CDPF、SCR was carried out,and optimized the structure furtherly.The internal flow field,reducing agent before SCR catalyst and particle distribution before DPF catalyst carrier were analyzed by three-dimensional simulation.