Turbine fuel testing

Specifications for gas turbine fuels prescribe test limits that must be met by the refiner who manufactures fuel however, it is customary for fuel users to define quality control limits for fuel at the point of delivery or of custody transfer. These limits must be met by third parties who distribute and handle fuels on or near the airport. Tests on receipt at airport depots include appearance, distfllation, flash point (or vapor pressure), density, freezing point, smoke point, corrosion, existing gum, water reaction, and water separation. Tests on delivery to the aircraft include appearance, particulates, membrane color, free water, and electrical conductivity. 

In drawing contracts and making acceptance tests, refer to the pertinent ASTM standards. ASTM Standards contain specifications (classifications) and test methods for burner fuels (D 396), motor and aviation gasolines (D 4814-03 and D 910-03), diesel fuels (d 975-03), and aviation and gas-turbine fuels (D 1655-03 and D 2880-03). 

ASTM. 1994a. Standard specification for aviation turbine fuel. American Society for Testing and Materials. Philadelphia, PA. 

Determining Water Separation Characteristics of Aviation Turbine Fuels by Portable Separometer (Microseparameter (MSEP) Test)... 

Testing of turbine fuels is handled in an analogous manner. Three sizes of test rigs have been utilized in the EPRI combustion test program-mini, sub-scale,and single combustor cans. 

Pillsbury, P.W. Cohn, A Mulik, P.R. Sihgh, P.P Stein, T.R. "Fuel Effects in Recent Combustion Turbine Burner Tests of Six Coal Liquids". (Submitted for presentation to the ASME Gas Turbine Conference, March 11-15, 1979.)... 

The feasibility of the dispersion fuels concept for applica--tion to gas turbine power plants is evaluated from disper-sion fuels formulation studies, from the results of single droplet tests directed toward demonstration of the droplet shattering process, and from the results of initial burner tests of dispersion fuels. Results demonstrate the existence of the microexplosion phenomenon in single-droplet combustion experiments. Gas turbine combustor tests indicate that fuel emulsification may alter favorably the efficiency of a practical gas turbine combustor without adversely affecting the turbine inlet temperature profile or CO, and smoke emissions. 

Landis, W.G., R.A. Matthews, A.J. Markiewicz, N.A. Shough, and G.B. Matthews. 1993a. Multivariate analyses of the impacts of the turbine fuel jet-A using a microcosm toxicity test.. Environ. Sci. 2 113-130. 

Community conditioning has been tested in a series of standardized aquatic microcosms using the turbine fuel JP-8 in a series of two back-to-back replicated experiments (Landis et al. 2000). The first experiment was for the typical 63-d duration of the protocol, but the second was extended to 126 d. As far as possible, the experiments were replicated with organisms taken from the same cultures, conducted in the same rooms, with the same lot of toxicant and with the same basic staff. As in previous microcosm experiments, the organisms were counted, the toxicant quantified, and the oxygen content and pH measured. Graphical methods and three multivariate clustering methods were used to follow the patterns within both experiments. 

In the test method for the determination of the acidity in an aviation turbine fuel (ASTM D-3242, IP 354), a sample is dissolved in a solvent mixture (toluene plus isopropyl alcohol and a small amount of water) and under a stream of nitrogen is titrated with standard alcoholic potassium hydroxide to the color change from orange in acid to green in base via added indicator p-naphtholbenzein solution. 

The aromatics content of aviation turbine fuel is included in the aviation turbine fuel specification (ASTM D-1655). Another test method for aromatics content (ASTM D-5186) involves the injection of a small aliquot of the fuel sample onto a packed silica adsorption column and elution with supercritical carbon dioxide as the mobile phase. Mono- and polynuclear aromatics in the sample are separated from nonaromatics and detected with a flame ionization detector. The chromatographic areas corresponding to the mono- and polynuclear and nonaromatic components are determined, and the mass percent content of each of these groups is calculated by area normalization. The results obtained by this method are at least statistically more precise than those obtained by other test methods (ASTM D-1319, ASTM D-2425). 

The determination of peroxide number of aviation turbine fuel is important because of the adverse effects of peroxides on certain elastomers in the fuel system. In the test, the sample is dissolved (unlike ASTM D-6447) in l,l,2-trichloro-l,2,2-trifluoroethane and is contacted within an aqueous potassium iodide solution. The peroxides present are reduced by the potassium iodide, whereupon an equivalent amount of iodine is released that is titrated with standard sodium thiosulfate solution and a starch indicator. 

Acids can be present in kerosene aviation turbine fuels because of acid treatment during rehning. These trace acid quantities are undesirable because of the possibility of metal corrosion and impairment of the burning characteristics and other properties of the kerosene. The potential for metals in kerosene is less than it is for aviations fuels, but several of the same tests can be applied (Chapter 6). 

D 4816 (1994) Test method for specific heat of aircraft turbine fuels by thermal analysis... 

D5001 Test Method for Measurement of Lubricity of Aviation Turbine Fuels by the Ball-on-Cylinder Lubricity Evaluator (BOCLE) Wear scar diameter... 

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