A diesel CFR engine was deeply modified to enlarge its operating field, enhancing speed and load control and to make measurements of the main parameters, aiming at the comparison of different renewable fuels. A grid of selected experimental conditions was defined, in which fuel consumption, exhaust emissions and in-cylinder pressure diagrams were recorded, giving information on fuels/blends, together with the standard Cetane Number. Experimental campaigns involving different renewable fuels were made on the influence of biodiesel content in tested blends on brake thermal efficiency, NOX and soot. The comparison of trends with literature results proved that the facility is a suitable tool for investigation on renewable fuels.

An extended investigation on the application of blends between diesel oil and used cooking oil methyl esters (UCOME) was developed on the automotive turbocharged diesel engine. Average engine parameters and indicated pressure diagrams were measured to calculate the most important operating, energy and environmental engine quantities, rate of heat release and related combustion parameters. Two commercial diesel oils were considered as reference fuels, the first with the conventional content of biodiesel (7%), the second with a larger amount (15%). Then, increased levels of UCOME were added, on a volumetric basis (20%, 40%, 55 or 60%), to analyze the influence of biodiesel content on engine behavior. The availability of an open electronic control unit allowed for a proper management of the exhaust gas recirculation circuit, variable nozzle turbine and injection parameters.

An optimal UCOME content (40%) was identified, corresponding to the highest values of brake thermal efficiency and lowest levels of specific NOX emissions, while soot emissions were always reduced when increasing biodiesel content. 

The investigation suggested that compensation strategies have to be considered for adapting engine control according to the renewable fuels.

Researchers

• Giorgio Zamboni
• Massimo Capobianco

Laboratories 

• Laboratorio di Motori a Combustione Interna

Publications

• Zamboni G., Capobianco M. Experimental Analysis of the Influence of Diesel-Used Cooking Oil Methyl Ester Blends on Efficiency, Emissions and Combustion Process in a Diesel Engine. EUBCE 2020, 28th European Biomass Conference and Exhibition, 2020.
• Zamboni G., Marelli S., Marmorato G., Capobianco M. An experimental apparatus for testing biodiesels based on a CFR engine – Setup and validation with different methyl ester blends. International Journal of Green Energy, vol.13-5, pp.481-488, 2016, doi:10.1080/15435075.2014.977439.
• Zamboni G., Marelli S., Marmorato G., Capobianco M. Experimental comparison of different diesel-biodiesel blends in a CFR engine. In: Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition (IMECE2012), Volume 6, Parts A & B-Energy, paper IMECE2012-86298, November 9-15, 2012, Houston, Texas, USA.