Abstract
Urea SCR system is effective post treatment device of diesel engine to remove NOx in exhaust gas. The purpose of this study is constructing simulation model capable of predicting spray behavior and NH3 concentration distribution. In order to achieve the purpose, it is necessary to clarify urea solution spray behavior injected by Urea SCR injector and NH3 concentration distribution generated by chemical reaction in experimental analysis. In this report, it is found that basic knowledge about the breakup mechanism of the free spray and the chemical reaction of urea solution droplets. The breakup mechanism of free spray is Rayleigh’s liquid column breakup that the liquid columns become bead form and break up into the droplets. Also, by increasing the surface area of urea solution using spray atomization, it is considered that chemical reaction rate is faster stunningly.
