Erdal TUNÇER
This study delineates experimental investigations and thermodynamic analyses conducted on a two-cylinder, two-stroke, air-cooled engine-standard for uncrewed aerial vehicles (UAVs)-operated with various gasoline–methanol fuel blends. Performance and emission metrics were obtained at five thrust levels (5, 10, 15, 20, and 26 kg) utilising five distinct fuel blends (M0, M10, M20, M30, and M40). The acquired data facilitated comprehensive evaluations of energy, exergy, and sustainability. At lower thrust levels, the minimal fuel consumption was observed with M0; at higher thrust levels, the minimum was recorded with M40. An increase in the methanol content within the fuel blends resulted in a notable reduction in CO 2 emissions; for instance, at a thrust of 26 kg, CO 2 emissions were 5.65% for M0 and 3.91% for M40. The highest efficiencies in terms of energy and exergy were achieved at a thrust of 15 kg across all fuel blends. Correspondingly, the maximum sustainability index was determined to be 1.39 for M40 at a thrust of 15 kg.