Development of Low NOx Capability on the Dresser Waukesha 275GL Series Engines

Dresser Waukesha’s 275GL engine family released in 2009 consists of a 214 liter (13,048 in³) 12 cylinder, and a 285 liter (17,398 in³) 16 cylinder engine derived from Waukesha’s ATGL family. These 1000 RPM engines are typically used in mechanical drive applications for natural gas compression at 2500 to 3300 kWb (3400–4500 bhp). Through market analysis and voice of customer (VOC) interviews, it was determined that lower Oxides of Nitrogen (NOx) output is essential for future engine sales in North America. Meeting this requirement with a minimal impact to fuel efficiency, fuel tolerance, turndown range, and altitude capability were also desired. To meet the lower NOx requirement, combustion was improved using Computational Fluid Dynamics (CFD) modeling and Design of Experiments (DoE) tools. To assure the low NOx emissions were maintained throughout the desired operating regime, an NOx sensor based air/fuel ratio control system was developed. This new NOx control capability is an enhancement to the Dresser Waukesha ESM™ engine control system. The result is an engine family that consistently meets stringent 0.5 g/bhp-hr NOx levels while maintaining fuel efficiency, fuel tolerance, and turndown range. Reduced combustion pressure in the 275GL Low NOx engine has also allowed a power increase over the original 275GL engine. This paper will discuss the testing and results of this development.