李江飞, 牛雨飞, 王龙飞, et al. Effects of Mixer on Urea Deposit in Selective Catalytic Reduction for China Ⅵ Diesel Engines[J]. 2021, 42(2): 31-37. DOI: 10.13949/j.cnki.nrjgc.2021.02.005.
In order to solve the problem of urea deposit in the selective catalytic reduction (SCR) aftertreatment system of a China Ⅵ diesel engine
two mixers of different structures were designed. Simulation analysis and comparison of urea impingement
urea track
air flow velocity
uniformity of velocity
uniformity of NH3 and pressure loss was carried out through the computational fluid dynamics (CFD) technology. Finally
the emissions and deposit performance of the two mixers were tested by engine bench. The CFD and test results show that Mixer 2 is superior to Mixer 1 in the air flow velocity
the uniformity of velocity and the uniformity of NH3
but has bigger pressure loss. The deposit weight of Mixer 1 was measured as 608g by engine bench test
which fails to meet the requirements of OEMs. And the deposit weight of Mixer 2 was measured as 6g
which meets the requirement of OEMs. The trends of the CFD analysis and test results are consistent
indicating that the CFD analysis is appropriate and effective.