A Comprehensive Assessment of Pinecone Oil–Based Biodiesel Blends in a Diesel Engine: Modeling and Optimization via Response Surface Methodology

The environmental impacts of fossil fuels and their impending depletion in the near future are bringing renewable energy sources to the forefront. Biodiesel is a renewable fuel obtained from vegetable and animal fats and can be used alone or blended with diesel fuel. In this study, the effect of biodiesel obtained from pinecones on engine performance and emissions was examined, and tests were conducted on a diesel engine with loads ranging from 500 to 2500 W by blending it with diesel fuel at ratios of 10%, 20%, and 30%. To determine the optimal conditions while reducing the number of experiments and saving time and money, optimization was performed using the response surface methodology (RSM), selecting engine load and biodiesel ratio as input parameters. A biodiesel ratio of 18.50% and an engine load of 1315 W provided the optimal conditions, and under these conditions, the response parameters of brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) engine performance values and carbon monoxide (CO), hydrocarbon (HC), carbon dioxide (CO2), and nitrogen oxides (NOx) emissions were obtained as 19.91%, 401.31 g/kWh, 0.0548%, 16.90 ppm, 4.87%, and 463.86 ppm, respectively. Pinecone biodiesel can be effectively used as an alternative fuel in diesel engines, especially at mixture ratios around 20%, reducing HC and CO emissions while maintaining acceptable performance levels.