Project run time: 18 June 2012 - 8 June 2016

Responsible Colleague:

•  Sascha Prehn

Description:

For the implementation of the project, a monovalent natural gas engine with spark ignition was built on the basis of a series diesel engine used in agriculture. Systematic combustion process investigations were carried out in accordance with the performance requirements and future exhaust emission legislation. The investigations show that for this engine category, the requirements, in particular the methane limit value, can only be met by a λ=1 combustion process with a three-way catalytic converter (optimised for methane). In the second phase of the project, a demonstration tractor was built based on the developed engine concept and tested for its practical suitability and comparability with a series-production diesel vehicle. The tests showed that the demonstrator can achieve up to 61% of the operating time of the same vehicle in diesel mode. The practical tasks examined (tilling, mulching, towing, etc.) could be performed without restrictions in gas mode. Further intensive application work on the engine control unit will enable improvements to be made in terms of response behaviour during transient engine operation. In terms of diesel operation, the GHG emissions of the vehicle concept have already been reduced by up to 15% (including methane). Compliance with the legally regulated pollutant emissions (nitrogen oxides, carbon monoxide and particulates) of EU Stage IV was ensured in almost the entire engine map with a stoichiometric combustion process in conjunction with exhaust gas recirculation. The engine concept also complies with the EU Stage V emissions standard, which is expected to be introduced in 2019.