Exhaust purification system

摘要

An exhaust purification system including an oxidation catalyst (1) disposed in an exhaust passageway (10) of an engine, and a filter (2) disposed downstream of the oxidation catalyst (1) in the exhaust passageway (10). The exhaust purification system further includes an outlet temperature setting section (3a) for setting, as an outlet target temperature, a target value for an exhaust temperature which is detected on the downstream side of the filter (2) in the exhaust passageway (10). The system further includes a heat loss quantity computing section (3c) for computing a heat loss quantity radiated from the filter (2) to outside the exhaust passageway (10) when exhaust discharged from the engine passes through the filter (2); and an inlet temperature setting section (3d) for setting, as an inlet target temperature on an upstream side of the filter (2), a temperature obtained by adding a loss temperature reduced by the heat loss quantity to the outlet target temperature.