Dosing module for exhaust post treatment system of vehicle

Abstract

A dosing module for an exhaust gas post treatment system of a vehicle, which may be used to inject a reducing agent along a flow direction of exhaust gas at a front side of a selective catalyst reduction (SCR) unit, may include a dosing main body having a connection portion that may be connected to the SCR unit and an inflow portion into which the exhaust gas flows, an injector that may be disposed at a boss portion that may be mounted on the dosing main body to inject the reducing agent into the dosing main body, and a guide member that may be disposed inside the dosing main body to guide the exhaust gas flowing into the dosing main body along a predetermined route.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]The present application claims priority to Korean Patent Application No. 10-2010-0125531 filed in the Korean Intellectual Property Office on Dec. 9, 2010, the entire contents of which is incorporated herein for all purposes by this reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]An exemplary embodiment of the present invention relates to an exhaust system of a vehicle. More particularly, the present invention relates to a dosing module of a selective catalyst reduction (SCR) unit for exhaust gas post treatment.[0004]2. Description of Related Art[0005]Generally, an exhaust system of an engine is provided with exhaust gas post treatment such as with a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), a selective catalyst reduction (SCR) unit, etc., so as to reduce diesel particulate matter (PM) and nitrogen oxide (NOx).[0006]Of these, a reducing agent (for example, a urea solution) is injected into...

AI Technical Summary

Benefits of technology

[0016]Various aspects of the present invention are directed to providing a dosing module for an exhaust gas post treatment system of a vehicle having advantages of substantially preventing a wall wetting phenomenon of a reducing agent and improving efficiency of a selective catalyst reduction (SCR) unit without injecting the reducing agent into a curved pipe and without disposing a mixer in the exhaust pipe.

[0025]The dosing module for an exhaust gas post treatment system of a vehicle prevents the wall wetting phenomenon in an exemplary embodiment of the present invention without injecting the reducing agent to the curved pipe and without disposing the mixer in the exhaust pipe, and the mixture of the exhaust gas and the reducing agent and the uniformity and the reaction activity thereof are improve regardless of the layout of the vehicle such that the efficiency of the SCR unit is increased.

Problems solved by technology

However, the spray depth of the reducing agent from the injector is increased in the conventional art such that the injected reducing agent is accumulated on the interior wall of the exhaust gas line, i.e., there is a problem that a wall wetting phenomenon is generated.

That is, the wall wetting phenomenon of the reducing agent that is injected is a cause of deterioration of purification efficiency of nitrogen oxide and activation of the SCR, and in a case that the liquid element of the reducing agent evaporates on the interior wall of the exhaust gas line, a solid residue thereof remains, and resultantly it becomes difficult to control the injection amount.

However, since the mixer is disposed in the exhaust gas line, material cost is increased thereby and there is a problem that the durability thereof is reduced.

Accordingly, it is necessary to secure the shape of the exhaust pipe to provide the appropriate positioning, the entire post treatment layout becomes complicated thereby, and there is a problem that it is difficult to dispose the injector on the layout.

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