Abstract
Due to the toxicity of ammonia generally used as a reducing agent in SCR system, urea solution, which is decomposed into ammonia (NH_3), was adopted in our system instead of ammonia. It is necessary to make the system compact because of the narrow space for installing it in the ship. Urea is thermally decomposed into ammonia in the mixing chamber where it is sprayed by nozzle. In this study, urea decomposition in hot gas was investigated for the optimum design of the mixing chamber in SCR system. Tests were accomplished at various temperature ranges and gas flow rates. The reaction equation for thermal decomposition of urea was derived. Also, the experimental results were verified by comparing to those of the CFD with the equation.
