Experimental validation of a virtual engine-out NOx sensor for diesel emission control

Abstract

Motivated by automotive emission legislations, a Virtual [Formula: see text] sensor is developed. This virtual sensor consists of a real-time, phenomenological model that computes engine-out [Formula: see text] by using the measured in-cylinder pressure signal from a single cylinder as its main input. The implementation is made on a Field Programmable Gate Array–Central Processing Unit architecture to ensure the [Formula: see text] computation is ready at the end of the combustion cycle. The Virtual [Formula: see text] sensor is tested and validated on an EURO-VI Heavy-Duty Diesel engine platform. The Virtual [Formula: see text] sensor is proven to meet the accuracy of a production [Formula: see text] sensor for steady-state conditions and has better frequency response compared to the production [Formula: see text] sensor.

Predicting instantaneous engine-out NOx emissions in a real-driving vehicle data scenario

“…Among the regulated pollutants, nitrogen oxides ( N O x ) emission has received a particular attention from the industry and the research community due to its harmful potential on health. 17–20 From empirical and physical models based on detailed or map-based process, 21,22 engine block vibration, 23 in-cylinder pressure signal, 24–29 variables available in the engine control unit (ECU), 30 or learning methods, 31–34 various approaches were explored for the real-time prediction of N O x emissions.…”

Development of a NOx Calculation Model for Low-Speed Marine Diesel Engines Based on Soft Measurement Technology

“…Based on constructing relevant variables, it can be divided into two categories: (1) Mathematical equations based on the working mechanism of the engine to form a more suitable NOx prediction through the appropriate simplification or additional consideration of the mixing and combustion conditions in the process of NOx formation [3][4][5][6][7][8][9][10]; and (2) use some physical signals (such as in-cylinder pressure, torque, etc.) during the working process of the engine to obtain intermediate variables through signal analysis and processing, and then combine the Zeldovich mechanism to analyze and deduce the generation of NOx to construct NOx predictive models [11][12][13][14][15]. The method of the physical mechanism model needs to be familiar with the formation mechanism of NOx under the characteristics of different models and fuel characteristics and conduct strict physical formula derivation, which can describe the in-cylinder combustion and the formation process of NOx more completely.…”