Technical Paper
A Predictive Tool for Engine Performance and NOx Emission
1998-10-19
982462
An engine cycle simulation program has been developed to predict both engine performance and NOx emission with reasonable accuracy. The program is a product that combines two programs, VIPRE™ and ALAMO_ENGINE, both developed at Southwest Research Institute (SwRI). VIPRE™ is a comprehensive tool for engine systems with intake and exhaust dynamics, emphasizing engine performance [1], while ALAMO_ENGINE is a program focusing on NOx prediction [2]. Demonstrations in this paper were based on a six-cylinder, turbocharged diesel engine with a high-pressure exhaust gas recirculation (EGR) loop. The EGR system is connected upstream of the intake manifold from the exhaust manifold located in the turbine entrance. A two-way butterfly valve is used to control the EGR rate. The major challenge in this modeling work is the prediction of engine performance and NOx emission in an acceptable and systematical fashion.