Combustion temperatures can be controlled by:
- Managing the charge air temperature. A reduction in charge air temperature of 3 deg C will reduce NOx emission by about 1%. It also increases fuel efficiency. Some manufacturers recommend the lowest possible charge air temperature for their engines equipped with effective scavenging air moisture catchers. Care should be taken not to reduce charge air temperature below dew point for older engines without moisture catcher. In any case, the moisture must not enter the combustion chamber.
- Retarding the injection timing. This can lower peak temperatures and NOx generation by up to 20%. However, retarding fuel injection may increase fuel consumption.
