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Surrogates for JP-8 have been developed in the high temperature gas phase environment of gas turbines. In diesel engines, the fuel is introduced in the liquid phase where volatility plays a major role in the formation of the combustible mixture and autoignition reactions that occur at relatively lower temperatures. In this paper, the role of volatility on the combustion of JP-8 and five different surrogate fuels was investigated in the constant volume combustion chamber of the Ignition Quality Tester (IQT). IQT is used to determine the derived cetane number (DCN) of diesel engine fuels according to ASTM D6890. The surrogate fuels were formulated such that their DCNs matched that of JP-8, but with different volatilities. Tests were conducted to investigate the effect of volatility on the autoignition and combustion characteristics of the surrogates using a detailed analysis of the rate of heat release immediately after the start of injection.

This paper presents the results of an experimental investigation on a single cylinder engine to validate a two-component JP-8 surrogate. The two-component surrogate was chosen based on a previous investigation where the key properties, such as DCN, volatility, density, and lower heating value, of the surrogate were matched with those of the target JP-8. The matching of the auto-ignition, combustion, and emission characteristics of the surrogate with JP-8 was investigated in an actual diesel engine environment. The engine tests for the validation of the surrogate were conducted at an engine speed of 1500 rpm, a load of 3 bar, and different injection timings. The results for the cylinder gas pressure, ignition delay period, rate of heat release, and the CO, HC, and NOx emissions showed a good match between the surrogate and the target JP-8. However, the engine-out particulate matter for the surrogate was lower than that for the JP-8 at all tested conditions.

This paper investigates the effect of boost pressure and intake temperature on the auto-ignition of fuels with a wide range of properties. The fuels used in this investigation are ULSD (CN 45), FT-SPK (CN 61) and two blends of JP-8 (with CN 25 and 49). Detailed analysis of in-cylinder pressure and rate of heat release traces are made to correlate the effect of intake pressure and injection strategy on the events immediately following start of injection leading to combustion. A CFD model is applied to track the effect of intake pressure and injection strategy on the formation of different chemical species and study their role and contribution in the auto-ignition reactions. Results from a previous investigation on the effect of intake temperature on auto-ignition of these fuels are compared with the results of this investigation.

The feasibility of using ultra low sulfur diesel (ULSD), synthetic paraffinic kerosene (S-8), military grade jet fuel (JP-8) and commercial B20 blend (20% v biodiesel in ULSD) in a power generator equipped with a compression ignition (CI) engine was investigated according to the MIL-STD-705C military specifications for engine-driven generator sets. Several properties of these fuels such as cetane number, lubricity, viscosity, cold flow properties, heat of combustion, distillation temperatures, and flash point, were evaluated. All fuels were tested for 240 hours at a stationary load of 30 kW (60% of full load) with no alteration to the engine calibrations. The brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), frequency, and power of the generator using S-8, JP-8 and B20 were compared with the baseline fuel ULSD.

The Office of the Secretary of the Defense (OSD), Advanced Systems and Concepts, established the OSD Assured Fuels Initiative, which aims to spark commercial production of clean fuels made from U.S. energy sources for use by the U.S. Military. The Department of Defense (DoD) will provide the “spark” by developing the fuel specifications needed, demonstrating and qualifying the use of these fuels in tactical ground vehicles, aircraft, and ships, and transitioning to the full-time use of these fuels in their fleets operating in the U.S. One such clean fuel, Fischer-Tropsch (FT) synthetic fuel, made using low-temperature FT technology, contains no aromatic compounds.

Clean, very low sulfur fuels produced from domestic resources are of interest to the U.S. Military to enhance supply security and reliability versus continuing to rely on the supply of fuels that are either manufactured from an increasing percentage of imported oil or imported in increasing amounts as finished products. [1]* Synthetic Fischer-Tropsch (FT) fuel is one type of fuel that can be produced from domestic resources. FT fuels can be produced from a variety of non-petroleum feed stocks, such as natural gas, coal, petroleum coke, or even biomass and various wastes. Starting with reforming or gasification processes, the FT technology first produces synthesis gas (syngas) which is subsequently processed to high-boiling hydrocarbons. These hydrocarbons are then hydrocracked, hydroisomerized, and/or hydroprocessed to produce the desired liquid fuels. The military has a Single Battlefield Fuel Policy which mandates use of the JP-8/JP-5/Jet A-1 aviation turbine fuels.