Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research on clean diesel engine technology: Reduce nitrogen oxide emissions and consumption

07.10.2015

The developers of modern advanced diesel engine technologies face a significant tradeoff when it comes to reducing both greenhouse gas and air emissions: Many measures which reduce nitrogen oxide emissions lead to a significant increase in fuel consumption. At the Autumn Meeting of the Research Association for Combustion Engines (FVV) in Würzburg scientists presented new approaches to reconcile both objectives.

To further improve the overall emissions characteristic of a diesel engine it is not sufficient to ensure the perfect functioning of the emission control system only. The utmost goal of engine developers is to even reduce raw emissions in the engine.

In addition to design measures, the engine control system thereby plays a crucial role: Different variable systems need to be aligned so that the emission limit values set by the legislator are met by the engine while consuming as little fuel as possible. Three of the most important interdependant calibration factors in a typical passenger car diesel engine are the injection time, the amount of exhaust gas recirculated into the cylinder and the air flow within the cylinder which can be influenced, for example, through connecting or disconnecting an inlet channel.

Scientists at ETH Zurich reported on a FVV research project proposing an optimised feedback emissions control system for diesel engines

The new technique is to calculate the combustion process in the engine by means of the so-called “heat curve” and to control the engine based on the results of this calculation. The emission control system of modern advanced diesel engines relies on the feedback of physical emission sensors, for instance for determining the NOx content in the exhaust gas.

"Even though our new calculation model could do perfectly without such physical sensors, we do not want to replace but supplement them by a virtual sensor network", explained Professor Dr Konstantinos Boulouchos, ETHZ Institute for Energy Technology.

Together with his colleagues from the Institute for Dynamic Systems and Control (IDSC), his research team validated the calcualtion results at the test bench: The emissions control system based on feedback via the virtual sensors delivered similar high quality results as were achieved by using an heuristic control strategy. This also includes dynamic test cycles as the WLTC (World Light-Duty Cycle Test), the introduction of which is currently under discussion.

An optimised high-performance engine control system may in the future also solve another problem of modern diesel engines: The combustion process is very dynamic – thus enabling a vehicle to react instantly when the driver steps on the accelerator pedal. Physical sensors detecting the raw emissions always respond with a delay of up to two seconds on the change in the engine operating conditions. Add to this the inertia of the exhaust gas aftertreatment systems. This leads for very short periods to increased emissions. “We are confident that we can halve these latency periods with modern control methods" said Boulouchos.

Japan and Europe researching together

Not only Europe but also Japan focuses its research activities on how the emissions of the diesel engine can be further reduced. Professor Dr Jin Kusaka from Waseda University in Tokyo presented to the auditorium the research priorities of the Japan Research Association of Automotive Internal Combustion Engines (AICE). AICE, too, is looking for ways to control the regeneration of the particle filter more accurately.

Since for each cleaning operation, additional fuel is injected, an exact knowledge of the actual load status over the life of the vehicle may result in significant fuel savings. For both oxidation as well as for SCR catalysts different concepts are examined that work at lower temperatures. This is important to reduce cold start emissions which are always increased. Another approach is to reduce the deposits caused by the exhaust gas recirculation in the engine. This would allow to permanently operate at higher exhaust gas recirculation rates, and the resulting drop in temperature would lead to lower NOx formation.

The AICE Research Association, founded in 2014 by the Japanese vehicle manufacturers, is a FVV partner organisation. Dietmar Goericke, Managing Director of the German Research Association for Combustion Engines (FVV) concluded:

"The fact that we in Europe as well as our partners in Japan continue our intense research activities on the diesel engine, shows the potential that lies in this combustion principle. The diesel engine is the most climate-friendly drive system designed for mobile applications. By means of further research efforts it will be possible cutting emissions even further even in real driving conditions."

Weitere Informationen:

http://www.fvv-net.de/en/home/home.html

Petra Tutsch | idw - Informationsdienst Wissenschaft

More articles from Machine Engineering:

nachricht Making lightweight construction suitable for series production
24.04.2017 | Laser Zentrum Hannover e.V.

nachricht It Takes Two: Structuring Metal Surfaces Efficiently with Lasers
15.03.2017 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Machine Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Molecular libraries for organic light-emitting diodes

24.04.2017 | Life Sciences

Research sheds new light on forces that threaten sensitive coastlines

24.04.2017 | Earth Sciences

Making lightweight construction suitable for series production

24.04.2017 | Machine Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>