Study On Hydrocarbon Adsorbent Mechanism Of New Type Absorber Of Gasoline Engine

Vehicle emissions have seriously impacted on air quality and threated to theecological balance, they are the main source of atmospheric pollution in our country.The gasoline engines exhaust large amounts of hydrocarbons (HC) in the cold startphase due to the surface quenching, the crack effect, and many other factors.However,the three-way catalytic converters for the after-treatment of exhaust gas could not meettheir activation temperature in the cold-start phase. Much of emissions got into the airand resulted in pollution. Therefore, how to deal effectively with the gasoline enginecold-start hydrocarbon has became one of the major problems in the field of engineemission control technology.To resolve this problem, a new type of HC adsorption device was designed in thepaper. Besides, the transfer and adsorption processes in the porous of HC adsorptionmaterial had been simulated and analyzed by used of computational fluid dynamicssoftware FLUENT and user-defined function (UDF).The major innovations andresearch works in the paper are as follows:(1) A heat transfering model and the corresponding UDF functions about theadsorption process have been drew by the mechanism of micro-pore volume filling ofthe particle types of physical adsorbent with the laws of mass conservation, momentumconservation and energy conservation. And the various thermodynamic parameters ofsimulate experiment for HC adsorption had been received from the conditions ofraising the engine speed from0r/min to3000r/min at a uniform velocity.(2) A new packed bed consists of ordered arrangement ring molecular sieves wasdesigned in the paper. The straggered, straight and the porous media types of newpacked bed models had been established, these models had been calculated with Ergunequation for a feasibility analysis. Results shown that, the porous media model wasavailable in the simulation of the new packed bed, and the simulation results of theporous media model had closer to the simulation results of the straggered packed bed.(3) The packed bed size and material had been selected, and then a new type ofadsorber had been designed. The adsorber had been simulated in the differentconditions, results showd that the appropriate increases of the initial mass flux ortemperature of the entrance could improve the adsorption efficiency.