Controlling PCCI Combustion with Mixed Fuel - Application of Flashing Spray to Early Injection

Suitability analysis of advanced diesel combustion concepts for emissions and noise control

“…Furthermore, in this concept the mixture formation process, and hence the rate of heat release, can be controlled by the injection settings [21]. Proper control of the combustion process increases the torque range of application of the PCCI concept and also the overall engine efficiency obtained, whereas pollution emissions and noise levels are both reduced.…”

Flash boiling spray of diesel fuel mixed with ethane and its effects on premixed diesel combustion

“…[ Table 3] [ In Fig.7, the relationships between the ∆P sat and the spray angle are plotted against the various ambient densities, ρ a . The open symbols are the data from the previous study using a heated mixed fuel of n-tridecane and i-pentane (Wada et al, 2007) and the solid symbols are the data obtained in this study. It is difficult to compare the data from the present and the previous study directly due to the differences in the definition of the spray angle, while it is possible to compare the gradient against the ∆P sat .…”

“…In addition to the above benefits, they suggested that the high volatility fuel induces flash boiling when the fuel is discharged into a combustion chamber with lower pressure than its saturation pressure [12]. Following Senda, Wada et al [13][14] applied mixed fuels consisting of i-pentane (C 5 H 12 ) and n-tridecane (C 13 H 28 ) to a premixed charge compression ignition engine with very early injection. Anitescu et al visualized the flash boiling sprays of the blends of gasoline and diesel fuel, injected into ambient air [15].…”

“…Relation between ∆P sat and the spray angle at various ambient densities, ρ a Open symbols: previous study(Wada et al, 2007) Solid symbol: present studyρ a = 1.5 kg/m 3 ρ a = 2.0 kg/m Plot of spray tip penetrations for different ethane fractions, V et V et = 0 vol.% V et = 30 vol.% V et = 50 vol.% V et = 60 vol.% Figure Profiles of in-cylinder pressures, p and apparent heat release rates, dQ/dθ at the injection timing, θ inj of -4 deg.CA ATDC V et = 0 % V et = 30 % V et = 50 % in indicated thermal efficiency, η i and maximum pressure rise rate, dp/dθ max with the injection signal incident timing, θ inj and the ethane fraction, V et V et = 0 vol.% 50 vol.% 60 vol.% Profiles of the apparent heat release rate, dQ/dθ at the optimum injection timings 50 vol.% 30 vol.% Plots of the ignition delays, τ ign and differences between the in-cylinder pressure and pressure on the bubble point curve, ∆P sat versus ethane fraction, V et at the optimun injection timings Figure Changes in maximum pressure rise rate, dp/dθ max and exhaust gas emissions with ethane fraction, V et at the optimum injection timing Changes in indicated thermal efficiency, η i and its related factors, cooling loss, φ cool ; combustion efficiency, η comb ; and degree of constant volume burning, η glh with ethane fraction, V et at the optimum injection timing Figure Plot of in-cylinder pressure, p and apparent heat release rate, dQ/dθ for the mixed fuels of Diesel fuel -ethane and Shellsol -i-octane (θ inj = -27 deg.CA ATDC) dp/dθ max = 1.3 MPa/deg.CA Diesel fuel + ethane dp/dθ max = 1.0 MPa/deg.CA Details of the indicated thermal efficiency, η i , combustion efficiency, η comb , cooling loss, φ cool , and NO x emissions of the fuel mixtures of Diesel fuel -ethane and Shellsol -i-octane (θ inj = -27 deg.CA ATDC) Diesel fuel -Ethane Shellsol + i-octane…”