Diesel engine from MTU – the centerpiece of the Vectron DE

The diesel engine that powers the Vectron DE is supplied by MTU Friedrichshafen, a subsidiary of Tognum AG. MTU Friedrichshafen is a diesel engine manufacturer with a long tradition and extensive experience in the railway sector. What sets the MTU diesel engine apart is its eco-friendliness, which is ahead of its time.

Historical timeline and background

The first rail vehicles with internal combustion engines were presented to the public back in 1887. In 1893, Rudolf Diesel published the principles underlying his engine, and the first diesel engine was built in 1897 with an efficiency of 27 percent. The first locomotive to be equipped with a diesel engine was developed in 1912. Today the diesel engine can look back on nearly 100 years of history as a drive unit for locomotives, a history in which MTU Friedrichshafen has also played a defining role.

The new engine concept

The Vectron DE’s diesel engine is a further development of the proven Series 4000 diesel engine. The typical feature of an engine with EGR technology is cooled exhaust-gas recirculation, whereby a portion of the exhaust gas is fed back into the combustion chamber. Mixing some of the exhaust gas with the combustion air significantly reduces the production of nitrogen oxides. The exhaust gas molecules prevent the rapid oxidation of fuel molecules, resulting in a lowering of temperature peaks and a reduction in NOx emissions. Improvements to the electronically controlled common rail injection system and low-emission combustion based on the Miller process complete the technical concept.

Increased requirements for eco-friendliness

As people become more environment-conscious, their expectations in terms of vehicles’ eco-friendliness continue to rise. This is reflected in the increasingly strict emission requirements imposed by law. European Directive EU97/IIIB, which will take effect on January 1, 2012, mandates an 88 percent reduction in particle emissions as well as a reduction in the emission of nitrogen oxides (NOx) of 40 percent compared with today’s standards.

Reduction in NOx values through exhaust-gas recirculation

As is the case with many technical challenges, there are a variety of different technical solutions for achieving the required limit values. The two most common solutions today are either the internal engine solution, namely exhaust-gas recirculation (EGR), or after-treatment using a process known as selective catalytic reduction (SCR). While exhaust-gas recirculation does not require any additional consumables in order to function, in the case of the SCR solution urea is injected into the exhaust-gas flow: in other words, an additional consumable must be carried on board. As a result, the SCR solution also requires a tank, pumps, piping, and a heating system. Vectron’s diesel engine uses the exhaust-gas recirculation process. This solution chosen by MTU prevents NOx emissions from the outset instead of producing them and then subsequently eliminating them.

Compact, high-performance particle filter

A particle filter is required for reducing particle emissions. The Vectron DE’s particle filter does not need any additional installation space. Nowadays, particle filtration occurs in the same space allotted to the exhaust silencer. The Vectron DE’s filter system is based on a ceramic honeycomb structure. The exhaust gases flow through its porous structure and particles are deposited as soot. The soot finally burns off due to self-regeneration, thanks to the catalytic coating. The entire filter process is monitored and controlled by the engine management system.

Installation of the first diesel engine in the Vectron DE