SCR mixer

A flow guide mixing pipe is arranged between a front shell and a rear shell, the periphery of the flow guide mixing pipe is sleeved with a baffle, the baffle divides an inner cavity into an air inletcavity and an air outlet cavity, the air inlet cavity is communicated with an air inlet, and the air outlet cavity is communicated with an air outlet. An opening is formed in the flow guide mixing pipe, the air inlet cavity and the flow guide mixing pipe are communicated, at least three layers of pore plates are arranged in the flow guide mixing pipe, a flow guide plate is arranged below the flowguide mixing pipe and located in the air outlet cavity, and the left side and the right side of the flow guide plate are bent downwards by a certain radian respectively. The flow velocity of tail gasflow is increased through the flow guide mixing pipe, the tail gas flow enters the flow guide mixing pipe after being accelerated and can be fully mixed with urea liquid drops, and the mixed tail gasflow accelerates to impact t