Mechanics, Friction & Noise
In modern diesel engines cylinder pressure provides information about the engine’s internal operations. However, cylinder pressure sensors are only partly suitable for series production. The FVV research project aims to show whether the engine management could eventually operate using information based on structure-borne sound. On the basis of test bed measurements it was possible to show the relation between cylinder pressure characteristics and structure-borne sound signals. In order to evaluate engine noise, the project partners developed models with which the diesel diesel engine knock could be calculated using volume and modulation of the structure-borne sound signals. In this way, engine noise components can be included in the engine management. And these results also form the basis for replacing cost-intensive cylinder pressure sensors with cheaper and more robust structure-borne sound sensors as input for the engine management. Additional investigations would provide the potential to optimise consumption, noise and exhaust emissions on the basis of a structure-borne sound-based engine management.
» The research results show new ways for optimised calibration and control strategies of diesel engines. In this way, the FVV makes a valuable contribution to reducing not only noise in the future, but especially raw material consumption and emissions of these engines. «
The question whether – and how – it is possible to improve a diesel vehicle's consumption, noise and exhaust emissions by integrating acoustic sensor signals in the engine management was the focus of this project.
Schematic diagram of a noise-controlled diesel engine with integrated noise coefficients in the engine control
Diagnosing the diesel engine knocking sound
Diesel engine knock: The knocking phenomena measure to what degree a diesel engine sound is considered an annoyance. It is determined on the basis of the acoustic parameters of volume and modulation.
The cylinder pressure is a central parameter for describing inner-engine processes, such as the heat release development for example, and thus is an important variable for engine management. As cylinder pressure sensors are only suitable for series production to a limited extent, alternatives are required. The question whether – and how – it is possible to improve a diesel vehicle's consumption, noise and exhaust emissions by integrating acoustic sensor signals in the engine management was the focus of this project.
A central part of the investigations was a detailed signal analysis at an engine test stand. This analysis should show which information concerning combustion, cylinder pressure, injection and the engine noise is found in a structure-borne bound signal and how these can be extracted. These different pieces of information were combined together and integrated into the engine control unit. For the variable of noise control the choice fell on the so-called diesel engine knock. The knocking phenomena measure to what degree a diesel engine sound is considered an annoyance. It is determined on the basis of the acoustic parameters of volume and modulation.
With the help of the newly developed engine management it is possible to replace the cost-intensive cylinder pressure sensors with cheaper and more robust structure-borne sensors. The newly developed correlation between structure-borne and cylinder pressure signals, derived from coherence and with the help of the Wigner-Ville-Transformation, enables this new engine design method. It also could be shown that the diesel engine knock is suitable as a regulation variable for engine management. In the next step, it would make sense to transfer the results to other diesel engines with larger rotational speed loads and to use this new method also for a cylinder-selective combustion control.
Noise Controlled Diesel Engine I | Analysis of injection and combustion sound of a diesel engine by means of modern signal processing methods for control and diagnosis | Project No. 1003 | AiF Funding ID 323 ZBG
Noise Controlled Diesel Engine II | Analysis of injection and combustion sound of a diesel engine by means of modern signal processing methods for control and diagnosis | Project No. 1070 | FVV Funds
Noise Controlled Diesel Engine III | Structure-borne noise-based diesel engine control - Optimisation and adaptation of the parameters | Project No. 1175 | AiF Funding ID 18251 BG
Public & FVV Funding
2009-09-01 to 2011-06-30 Part I
2011-06-01 to 2011-12-31 Part II
2014-06-01 to 2016-09-30 Part III
Dipl.-Ing. Michael Joerres
1 | Institute of Mobile Systems (IMS) | Chair of Energy Conversion Systems for Mobile Applications (EMA) | Otto-von-Guericke University Magdeburg (OVGU)
Head of Research:
Prof. Dr.-Ing. Dr. h. c. Helmut Tschöke | I+II
Prof. Dr.-Ing. Hermann Rottengruber | III
Dipl.-Ing. Karsten Hintz | I
Dipl.-Ing. Sebastian Lucas | II
Sebastian Schneider, MSc | III
2 | Chair of Electronic Measurement and Diagnostic Technology (MDT) | Department of Energy and Automation Technology (IEA) | TU Berlin
Head of Research:
Prof. Dr.-Ing. Clemens Gühmann | II+III
Marco Decker, MSc | II
Dr.-Ing. Jan Hendrik Hermann Carstens | III
3 | IAV GmbH – Automotive Engineering
Head of Research:
Dipl.-Ing. Enrico Neumann | II
Dipl.-Ing. Jürgen Nobis | II
Research & Technology Performers
Research Association for Combustion Engines eV
Lyoner Strasse 18
60528 Frankfurt am Main
T +49 69 6603 1345