This study experimentally investigates the performance characteristics of a light-duty gas turbine engine operating on Kapok Flabellifer Methyl Ester (KFME) biodiesel blends as potential alternative aviation fuels. Five fuel blends such as KFME20, KFME40, KFME60, KFME80, and neat KFME (KFME100)—were evaluated over a range of engine load conditions to examine their effects on thermal efficiency, thrust-specific fuel consumption (TSFC), and emissions behavior. The experimental results indicate that lower biodiesel blending ratios deliver superior overall performance. In particular, KFME20 and KFME40 exhibit an optimal balance between combustion efficiency and fuel economy. Among all tested fuels, KFME20 achieved the highest thermal efficiency, with an improvement of up to 27.8% compared to neat KFME, primarily due to improved oxygen–fuel mixing, enhanced atomization, and increased combustion stability. Additionally, KFME20 demonstrated a reduction in TSFC of approximately 20%, reflecting more effective energy conversion and improved fuel utilization. Conversely, higher biodiesel concentrations were associated with increased NOₓ emissions, attributed to elevated combustion temperatures and intensified oxidation reactions inherent to oxygenated fuels. Based on the combined assessment of performance and emissions, KFME20 is identified as the most promising blend for light-duty gas turbine applications. For operational scenarios subject to stringent NOₓ emission limits, KFME20 or KFME40 are recommended, offering acceptable trade-offs between engine efficiency and environmental compliance.
Fernandez et al. (Mon,) studied this question.