Effects of Intake Air Humidity on the NOX Emissions and Performance of a Light-Duty Diesel Engine

The effects of intake air humidity on the performance of a turbo-charged 4-cylinder diesel engine have been investigated. The relative humidity of the intake charge was varied from 31 to 80% at a fixed ambient air temperature of 26°C. The intake humidity was controlled to within ±1% of the desired value by using a steam generator-equipped intake-air conditioning system. The tests were conducted at 3 load points (4.1, 9.1 and 15 bar BMEP) at …