Canister Design And Performance Research Based On China Vi Emission Regulation

With continuous development of automotive industry,automotive industry is playing an increasingly important role in promoting the rapid development of China's economy.With the rapid development of industry,environmental problems have followed.In particular,the important effects of exhaust pollution and evaporative pollutants on haze and ozone.In December 2016,National issued the official manuscript of “Limits and measurement methods for emissions from light-duty vehicles(China 6)”.Compared with the previous standards,China 6 tightens the limits of evaporative emission and increases the requirements for refueling emission control.Based on the analysis of China 6 emission standards,this paper designs and studies the core component carbon canister system of the evaporative emission control system and the refueling vapor recovery control system,and carries out the design scheme through the combination of simulation analysis and experimental verification.Specific research content and main conclusions are as follows:(1)For type IV test and type VII test in China 6 regulations,38? ambient temperature and 163 BV desorption volume cause the canister to be fully desorbed which have a direct impact on the test results to reducing the evaporative emission.(2)Different types of mixed columnar carbon powder can reduce emission value by about 50%.When confirming the volume of the canister,ensure that it has sufficient working capacity and will not be penetrated by fuel vapor.The key to designing the refueling vapor recovery control system is the system pressure drop.The system pressure drop should be less than 3.45 kPa to ensure that the fuel vapor flows into the canister for recovery and purification,and at the same time reduces the risk of PSO(Pre-mature Shut Off).The heat source should be avoided in the setting of the canister to ensure the stability of working ability.(3)The strength and flow analysis of the canister system can confirm whether the canister has a resonance risk,the flow field distribution calculation can see the flow distribution of the gas flow inside the canister,determine whether there is a dead angle inside the canister which will affect the adsorption efficiency.The internal resistance and CFD simulation analysis verified the smoothness of the refueling and ensured that there was no risk of PSO for ORVR system.(4)The vehicle evaporative emission test result is 0.54g/test.Compared with the results of the American standard vehicles announcement,we still need to improve the emission limit control.Through the refueling test,it is determined that the vent circulation pipe plays an important role in maintaining the system pressure balance during the refueling process,effectively reducing the HC emission.in addition,the canisters should be aged before the Type IV and Type VII tests to ensure work capacity is stable?...