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This paper investigates the performance of an indirect injection (IDI) diesel engine fueled with Bu25, 75% ultra-low sulfur diesel (ULSD#2) blended with 25% n-butanol by mass. N-butanol, derivable from biomass feedstock, was used given its availability as an alternative fuel that can supplement the existing limited fossil fuel supply. Combustion and emissions were investigated at 2000 rpm across loads of 4.3-7.2 bar indicated mean effective pressure (IMEP). Cylinder pressure was collected using Kistler piezoelectric transducers in the precombustion (PC) and main combustion (MC) chambers. Ignition delays ranged from 0.74 - 1.02 ms for both operated fuels. Even though n-butanol has a lower cetane number, the high swirl in the separate combustion chamber would help advance its premixed combustion. The heat release rate of Bu25 became initially 3 J/crank-angle-degree (CAD) higher than that of ULSD#2 as load increased to 7.2 bar IMEP.

This study investigates the use of a natural gas derived fuel, synthetic Fischer-Tropsch (F-T) paraffinic kerosene, in both it’s neat form and blended with ultra-low sulfur diesel (ULSD#2), in a naturally aspirated indirect injected engine. A blend of a mass ratio with 20% of the F-T fuel and 80% ULSD#2 was studied for its combustion characteristics, emissions, and efficiency compared to conventional ULSD#2 at a constant speed of 2400 RPM and operating at IMEP range from 4.5 to 6.5 bar. The F-T blend produced ignition delays 17% shorter than ULSD#2 resulting in slightly lower peak apparent heat release rates (AHRR) along with decreased peak combustion temperatures, by up to 50°C. Nitrogen Oxide (NOx) emissions of the F-T blend decreased by 4.0% at 4.5 bar IMEP and at negligible amounts at 6.5 bar IMEP. The F-T blend decreased soot significantly at 5.4 bar IMEP by 40%. Efficiencies of the F-T blend were similar to ULSD#2.

In order to advance the current research engine to operate in advanced combustion modes such as reactivity controlled compression ignition RCCI a diesel common rail fuel injection system for the experimental research engine has been designed and developed through testing the hydraulic, electrical and electronics, mechanical subcomponents, and the controls strategies. This study presents the process taken based on the verification and validation model of design and development for the fuel injection system incorporating hardware-in-the-loop (HIL) testing prior to engine operation and subsequent engine validation. Software verification was completed through signal converting circuits to confirm precise injection timing and to test the system in a mean effective model to incorporate a PI speed controller along with consistent rail pressure.

In this study, the combustion and emissions characteristics of n-butanol/GTL and n-butanol/ultra-low sulfur diesel (ULSD) blends are compared in a single-cylinder experimental diesel engine. The n-butanol was blended with a Fischer-Tropsch (FT) gas-to-liquid (GTL) fuel, at 25% and 50% mass. N-butanol was also blended with ULSD at the same mass ratios. FT fuels are an attractive alternative to petroleum based fuels because they can be used as a drop-in fuel with existing infrastructure. N-butanol is renewable fuel capable of being produced from waste biomass sources. The investigations were conducted at 1500 rpm and three loads of 2.75, 4.75, and 6.75 IMEP, representative for the research engine. 15% exhaust gas recirculation was utilized along with a supercharger to increase the intake pressure to 1.2 bar absolute. Neat ULSD and GTL, respectively, were investigated as a baseline.

This study investigates combustion and emissions of Jet-A in an indirect injection (IDI) compression ignition engine and a direct injection (DI) compression ignition engine at 4.5 bar IMEP and 2000 RPM. The Jet-A was blended with ULSD that resulted in 75%Jet-A and 25% ULSD#2 by mass. Both engines were instrumented with Kistler pressure sensors in the main chamber and the IDI engine had a second pressure sensor in the pre-chamber. Combustion properties and emissions from both engines using the 75% jet-A blend (75Jet-A) were compared to a baseline test of Ultra Low Sulfur Diesel #2 (ULSD). The ignition delay was shorter when running on 75Jet-A compared to ULSD in the DI engine. For ULSD, the ignition delay was 1.8 ms and it reduced to 1.7 ms when operating on 75Jet-A (difference of 6%). In the IDI engine the ignition delay for both fuels was 2.3 ms based off the gross heat release in the Pre-Chamber.

In this study, Premixed Charge Compression Ignition (PCCI) was investigated with alternative fuels, S8 and n-butanol. The S8 fuel is a Fischer Tropsch (FT) synthetic paraffinic kerosene (SPK) produced from natural gas. PCCI was achieved with a dual-fuel combustion incorporating 65% (by mass) port fuel injection (PFI) of n-butanol and 35% (by mass) direct injection (DI) of S8 with 35% exhaust gas recirculation. The experiments were conducted at 1500 rpm and varied loads of 1-5 bar brake mean effective pressure (BMEP). The PCCI tests were compared to an ultra-low sulfur diesel no. 2 (ULSD#2) baseline in order to determine how the alternative fuels effects combustion, emissions, and efficiencies. At 3 and 5 bar BMEP, the heat release in the PCCI mode exhibited two regions of high temperature heat release, one occurring near top dead center (TDC) and corresponds to the ignition of S8 (CN 62), and a second stage occurring ATDC from n-butanol combustion (CN 28).