On The Possibility to Reduce Diesel Engines Emissions by Operating with Biodiesel B20 in PPC Mode

摘要

Using diesel-biodiesel blends in Diesel engine has been highlighted to offer a good opportunity in reducing the exhaust emissions for particular engine operating conditions. The blended diesel-biodiesel with up to 20% biodiesel in petroleum diesel fuel (B20) is in production and available for use in USA being considered as viable path to be followed in the effort to reduce the effect of the greenhouse gas emissions issued by the operation of heat engines. Although previous studies investigating the effect of B20 on engines emissions led to some contradictory results, the life cycle analysis performed on the well-to-wheel base shown that 35% reductions of CO_2 emission, in respect to fossil fuels operation are possible. The association of this alternative fuel use with some new combustion concepts as homogeneous charge compression ignition (HCCI) premixed charge compression ignition (PCCI) or partially premixed combustion modes (PPC) may amplify these potential reductions. The present study continued the investigation on B20 effects by performing a set of comparative experimental tests on a conventional direct injection tractor diesel engine running alternatively with B20 and petroleum diesel fuel at 2400 rpm speed and 60% load. The possibilities to enhance the effects of B20 fuel by PPC combustion operation mode were explored by numerical simulations using the AVL BOOST v2013.2 code. It was basically found that further improvements in decreasing emissions of Diesel engines operating with B20 can be obtained without significant changes in Diesel engines structure and adjustments.