Bahattin Topaloglu

Combustion performance and emissions of diesel/biodiesel blended fuels in a residential reverse flame boiler

This paper presents an experimental study on the performance of diesel and biodiesel blended fuels in a water-cooled flame tube boiler. The combustion performance and gas emissions of B10, B20 and B30 were studied and these were compared with the diesel fuel. To investigate the combustion characteristics of biodiesel blends, including pure diesel, the temperature distributions in the combustion chamber and smoke tube, exhaust temperature, and exhaust gas emissions were determined. The results showed that the size of the peak temperature zones in the combustion chamber decreased gradually from B0 to B30. As a consequence of reduced temperatures in combustion chamber, NOx emissions decreased from 53 to 47 ppm and CO emissions increased slightly from 9.6 to 12.8 ppm. Also, CO2 emissions decreased from 13.2 to 12.8 with increasing biodiesel ratio in the diesel fuel. Results also showed that the thermal efficiencies of diesel/biodiesel blended fuels remained almost the same.

Second law analysis of a spark ignition engine under high values of ignition retard

The availability analysis of an Spark-Ignition (SI) engine under High Values Ignition Retard (HVIR) was investigated. Liquefied Petroleum Gas (LPG) was used as fuel. The results obtained in this paper may provide guidance to determine the proper ignition retard timing for cold-start emissions control. Results showed that cylinder pressure, availability transfer by heat and availability transfer by work significantly decreased as the spark timing was changed from normal to most retarded timing. Finally, as the spark timing was changed from normal timing to the most retarded timing, the availability transfer due to net exhaust flow and availability destruction due to combustion were significantly increased.