Study on the Effect of Precious Metal Content on Emission Characteristics of Hybrid Electric Vehicle
The research focuses on the exhaust emission characteristics and emission reduction effects of hybrid electric vehicle with 2.0L GTDI engine.A series of three-way catalysts with different Pd and Rh contents were designed,and the light-off performance,air-fuel ratio windows,and vehicle emission per-formance under WLTC cycle were tested before and after catalyst aging.The original emission test results show that the exhaust temperature of this vehicle is between 300-560℃.Compared to gasoline vehicles,the exhaust temperature is lower,the air-fuel ratio is higher,and the overall mixture is lean;During the cold start stage,it is difficult to control THC and NOx emissions.With the series of catalysts,the emission test results of the vehicle show that the light-off performance of the catalyst is linearly related to the total content of precious metals;The pollutants can quickly achieve complete reaction with the rising of content for precious metals.The vehicle emission test results of fresh catalysts show that the total content of pre-cious metals has a greater impact on the vehicle emissions of THC and NOx than on CO.For aging catalyst,the Pd content in the catalyst has a significant impact on the vehicle emissions of THC,while the Rh con-tent has a significant impact on the overall NOx emissions;The vehicle emissions of CO are less affected by the total content of precious metals,the vehicle emissions of CO are basically the same when the total content of precious metals exceeds 2.21 g.The research results can provide reference for the study of precious metal reduction of three-way catalysts for hybrid electric vehicles.
Hybrid electric vehicleThree-way catalystPrecious metal contentWLTC cycleEmissionBench test
万方数据
维普
