Investigation of a gas engine for agricultural machinery and progress report of field tests with a demonstration tractor

To present a monovalent natural gas operation, a functional model is derived from a series diesel engine for agricultural use. On the test engine, systematic studies on the combustion process are carried out by cylinder pressure indication and exhaust-emission measurement. The studies show that the exhaust gas limits in force since 2014 can be met with a stoichiometric combustion concept and a three way catalytic converter optimised for the methane oxidation. In a second step an agricultural tractor was modified for the operation with natural gas. After first field test the tractor is used in the daily operation. Under a typical range of application the tractor can be used for 10 hours withoutrefuelling.