Study on the flow effects of an exhaust system by mixer modeling

Abstract

This study focused on the mixer used in a SCR System, a technology being developed to conform to exhaust gas regulations which have recently become stricter. This study includes an analysis on fluid effect at each mixer to optimize the location of the catalyst and optimized modeling to interpret the current condition of the exhaust system. ANASYS of commercial program was utilized to analyze the fluid effects. Parameters were set up of four variable at 1,000rpm from 1,000rpm to 4,000rpm and three models were used for the analysis. The maximum pressure distribution was measured at mixer 2 and total pressure distribution was measured at mixer 2 as the largest amount, followed by mixer 1 and mixer 3 respectively. Low pressure was measured at the end-central part of the mixer since the pressure is distributed from the central axis and towards the outside. The largest velocity distributional area, 210m/s, was measured at mixer 2 during analysis by velocity. A low velocity region was captured at the end-central part of the mixer since flow was created towards the outside. The analysis showed that mixer 1 was the most effective in pressure distribution and uniformity. 944 Mun-seok Choe et al.

A Study on the Factors Affecting the Uniformity of Urea and Exhaust Gas Using an SCR Simulator

“…Also, though a diesel engine has advantages that torque change is small and the total quantity of exhaust gas is small when compared to those of a gasoline engine, it has a problem that the exhaust gas contains much Particulate Matter (PM) and NOx. Although environmental pollution pointed out to be a shortcoming of diesel engine has been much more improved than before, the quantities of PM and NOx discharged from a diesel engine are still bigger than those from vehicles that use another fuel [2,3]. Also, as PM is known to have a direct effect on human lungs and NOx has a problem of generating ozone or acidic rain, reduction of PM and NOx continue to be an important challenge [4].…”