Study on the Combustion Characteristics of Diesel/Furan Blended Fuel Based on Visualization

With the energy crisis, intensifying environmental problems and increasingly stringent emission regulations posing further challenges to the development of internal combustion engine, exploring renewable green energy sources has become an effective solution. In this paper, three test fuels were blended with diesel fuel at 0%, 10% and 20% by volume, respectively, and were recorded as D100, D90F10 and D80F20. Images of the combustion of each fuel at each injection pressure were taken by direct photography at a background pressure of 4 MPa and a background temperature of 800 K. The blending of furan in diesel fuel resulted in a longer stall period, shorter burn duration and a significant increase in combustion temperature. Relative to D100, the of the fuel blend increases, with D80F20 having the largest flame lift-off length. Compared to D100, the KL of the fuel mixture is significantly lower, that is the soot emissions are reduced, with the maximum reduction of 75.4% and 91.5% after the accumulation of D90F10 and D80F20. As D80F20 has the best atomisation, sufficient premixing time and longest flame lift-off length, all of which promote full flame combustion, D80F20 has the lowest soot emissions, even close to 0 at 140 MPa injection pressure. Relative to D100, the mixed fuel flame luminous intensity is significantly reduced, with the maximum reduction in total luminous intensity for D90F10 and D80F20 being 49.3% and 76.9%.