A Physical Two-Zone NOx Model Intended for Embedded Implementation

Summary, in English

This paper offers a two-zone NOx model suitable for vehicle on-board, on-line implementation. Similar NOx modeling attempts have previously been undertaken. The hereby suggested method does however offer clear and important benefits over the previously methods, utilizing a significantly different method to handle temperature calculations within the (two) different zones avoiding iterative computation. The new method significantly improves calculation speed and, most important of all, reduces implementation complexity while still maintaining reasonable accuracy and the physical interpretation of earlier suggested methods. The equations commonly used to compute NOx emissions is also rewritten in order to suit a two-zone NOx model. An algorithm which can be used to compute NOx emissions is presented and the intended contribution of the paper is a NOx model, implementation feasible for an embedded system, e.g. embedded processor or embedded electronic hardware (FPGA). For that purpose parts of the algorithm can be pre-computed and stored in tables allowing significant acceleration of the computation.

• Author: Bengt Johansson; Carl Wilhelmsson; Per Tunestål; Rolf Johansson; Anders Widd
• Department/s: Combustion Engines; Department of Automatic Control
• Publishing year: 2009
• Language: English
• Publication/Series: SAE Technical Papers
• Full text: - 2 MB; Download statistics
• Links: http://dx.doi.org/10.4271/2009-01-1509
• Document type: Conference paper
• Publisher: SAE
• Topic: Other Mechanical Engineering
• Keywords: NOx; Embedded system; Model; Engine; FPGA; NO
• Conference name: SAE World Congress, 2009
• Conference date: 2009-04-20 - 2009-04-23
• Conference place: Detroit, Michigan, United States
• Status: Published
• Project: Competence Centre for Combustion Processes
• ISBN/ISSN/Other: SAE 2009-01-1509