Study on the Flow Characteristics of Urea-SCR Swirl Injector according to the Needle Lift Profile

Urea-SCR용 스월 인젝터의 니들 리프트 형상에 따른 유동특성에 대한 연구

Gwak, Eun-Jo;Park, Sung-Young

  • Received : 2016.03.28
  • Accepted : 2016.06.02
  • Published : 2016.06.30


In this study, a computational simulation of the internal flow characteristics was carried out for a Urea-SCR Injector. A single hole swirl injector with a swirl disk and slanted nozzle was used in this simulation. The maximum needle lift and opening velocity were selected as the design parameters. To analyze the unsteady internal flow characteristics of the Urea-SCR injector, the moving grid technique was applied to simulate the delicate needle movement. According to the simulation results, the injected mass flow rate from the Urea-SCR injector decreased with increasing needle opening velocity and maximum needle lift. This is because the Urea-solution tends to fill the empty space that the needle previously occupied. The swirl flow is decreased as the flow goes through the injector nozzle, because of the friction with the nozzle wall. Also, during the maximum needle lift period, the swirl coefficient and mean swirl coefficient increase with increasing needle lift. The results of this study may be used as the basic design data of related injectors.


Computational simulation;Injector;Internal flow;Moving grid;Urea-SCR


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Supported by : 공주대학교