Cesar Carapia, Georgia Southern University, Statesboro, GA
Title: RCCI with N-butanol for the Reduction of NOX and Soot Emissions
Biography: Since my childhood I aspired to become an Engineer in the automotive industry to make a lasting impact on society and the environment. This motivated me to become the first within my family to attend and graduate from a university. As I continue my education in the Master’s program at Georgia Southern University under Professor Soloiu's supervision, I strive to expand my engineering knowledge and one day influence others to do the same.
Abstract: The focus of this study is to reduce harmful NOX and soot emissions EPA emission standards from tier 0 to tier 4, of a direct-injected engine utilizing reactivity-controlled compression ignition (RCCI) combustion strategy without EGR, boost, or after treatment. RCCI was achieved using port fuel injection of the low reactivity bio-alcohol, n-butanol, and a direct injection of the high reactivity ULSD #2. A Constant Volume Combustion Chamber was utilized to determine the ID for n-butanol and was determined to be 15 times longer than that of ULSD. The emissions and combustion analysis was conducted in a single-cylinder experimental engine at 1500 RPM at a load of 4 bar IMEP; the baseline for emissions comparison was conducted using CDC with an injection timing of 16° BTDC at a rail pressure of 800 bar. Experimental analysis was conducted with an injection timing of SOI-1 60° BTDC and SOI-2 25° BTDC at a rail pressure of 400 Bar. RCCI was achieved utilizing 75% by mass PFI of n- butanol with 25% ULSD DI, showed a simultaneous reduction of both NOX and soot emissions at a rate of 96.2% and 98.7% respectively with an increase in UHC emissions by a factor of 5. Ringing Intensity was also significantly reduced for Bu75ULSD25 with a reduction of 62.1% from CDC. Overall soot emissions did achieve tier 4 standards with further research needed for the reduction of UHC emissions.
Patrick C. O'Donnell, Clemson University International Center for Automotive Research
Title: Varying the Injection Timing of Wet Ethanol in LTC: A CFD Simulation Study
Biography: Patrick C. O’Donnell attended Stony Brook University for his undergraduate studies as a double major in Mechanical Engineering and Applied Math and Statistics. He is currently pursuing graduate studies at Clemson University International Center for Automotive Research. His work focuses on advanced internal combustion concepts such as HCCI and TSCI.
Abstract: Computational Fluid Dynamics (CFD) modeling was used to investigate the effects of the injection of wet ethanol at various timings during the intake stroke in a diesel engine with a shallow bowl piston. Thermally Stratified Compression Ignition (TSCI), a modification to Homogenous Charge Compression Ignition (HCCI), has been proposed to expand the operating range of HCCI by broadening the temperature distribution in the cylinder prior to ignition. TSCI can be enabled by using either direct water injection or a split injection strategy of water-fuel mixture that injects once in both the intake and compression strokes. This current study focuses on isolating the effects that the injection during the intake stroke has on the temperature and equivalence ratio distribution before the onset of the combustion process. A CONVERGE 3-D CFD model of a single cylinder diesel research engine using Reynolds Averaged Naiver Stokes (RANS) turbulence modeling was developed and validated against experimental data. Then, five cases of injection timing with an included angle of 60 degrees were simulated from -330 CAD to -210 CAD BTDC in increments of 30 degrees and four cases with an included angle 150 degrees were simulated from -330 CAD to -240 CAD BTDC also increments of 30 degrees. The results show that different injection timings create varying and inconsistent effects on the thermal stratification and fuel-air mixing.