Exhaust system for commercial vehicle, has cooling passage formed between wall and outer parts of exhaust system, where surface temperature of outer parts is adjustable to specific value by introduction of cooling medium into passage

摘要

The system (10) has an exhaust gas after-treatment device (12) isolated from the surroundings by a wall (14). A cooling passage (20) is formed between the wall and outer parts (16, 18) of the exhaust system which are made of thermal protection metal sheets. A fan supplied cooling medium i.e. cool air, into the cooling passage for adjusting the surface temperature of the outer parts to less than 60 degrees centigrade. The cooling passage is coupled with a cooling circuit containing cooling fluid e.g. oil, for introducing the cooling fluid as the cooling medium into the cooling passage. The exhaust gas after-treatment device is a particulate filter and a selective catalytic reduction (SCR) converter. The outer parts are formed as heat exchangers. An independent claim is also included for a method for operating an exhaust system for a vehicle.