The Quantification and Improvement of the Thermal Stability of Aviation Turbine Fuel

Studies of the propensity of aviation turbine fuels to lacquer engine oil-coolers that were described in an earlier paper have been extended to cover a wider range of fuels. Fuel performance was found to vary widely; some fuels were liable to lacquer oil-coolers to the extent of producing significant losses in efficiency at the most severe operating conditions currently encountered. Oxidation studies conducted in parallel with the rig investigations indicate that a fuel’s performance is strongly dependent on its tendency to initiate radical oxidation reactions. The relatively high initiation rate of less stable fuels is believed to be due in part to their trace content of metals that catalyze oxidation reactions. Accordingly, an approved metal deactivating additive has been examined as a means of improving the performance of such fuels.

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The Thermal Stability of Aviation Fuel

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/84-gt-69 ◽

1984 ◽

Author(s):

J. S. Mills ◽

F. R. Edwards

Keyword(s):

Thermal Stability ◽

Research Tool ◽

Aviation Fuel ◽

Engine Oil ◽

Thermally Stable ◽

Fuel System ◽

Flow Rates ◽

Aircraft Fuel ◽

Oil Cooler ◽

Thermal Stability Of

The propensity of aviation turbine fuels to produce deposits in the oil-cooler and filter sections of aircraft fuel systems has been examined using a rig that simulates the fuel system of an aircraft and which employs realistic flow rates. All the fuels examined were found to be thermally stable up to temperatures in excess of those currently attained in engine oil coolers. Comparison with results obtained with the JFTOT indicates that this is not suited for use as a research tool.

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KARBON LİF ÜRETİMİNDE POLİAKRİLONİTRİL ELYAFLARIN TERMAL OKSİDASYONU

Euroasia Journal of Mathematics, Engineering, Natural and Medical Sciences ◽

10.38065/euroasiaorg.674 ◽

2021 ◽

Vol 8 (17) ◽

pp. 160-170

Author(s):

Mahbubor Rahman ◽

Tuba DEMIREL ◽

Ismail KARACAN

Keyword(s):

Thermal Stability ◽

Aqueous Solution ◽

Thermal Oxidation ◽

Oxidation Process ◽

Ammonium Persulfate ◽

Oxidation Reactions ◽

Carbon Yield ◽

Thermal Stability Of ◽

Pan Fibers

Thermal oxidation of polyacrylonitrile (PAN) fibers was accomplished at temperatures up to 250°C for different oxidation times. Chemical integration of PAN fibers with an aqueous solution of ammonium persulfate was performed before starting thermal oxidation. The results recommend that ammonium persulfate integration enhanced the oxidation reactions of the PAN fibers and resulting in enhanced thermal stability. Ammonium persulfate impregnation followed by the oxidation process in the air environment leads to significant deviations in the characteristics of PAN fibers. To perform structural characterization of the raw and ammonium persulfate (APS) incorporated and stabilized samples, XRD, IR-spectroscopy, TGA was executed in this study. Investigation of the XRD and infrared spectroscopy outcomes recommended quick aromatization reactions with growing oxidation periods. The TGA traces indicated a comparative enhancement in the thermal stability of the PAN fibers by the increased carbon yield with the rise of the oxidation time. The overall findings recommend that ammonium persulfate incorporation was very influential in stimulating the oxidation process.

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Alternative Aircraft Fuels

Journal of Engineering for Power ◽

10.1115/1.3446437 ◽

1979 ◽

Vol 101 (1) ◽

pp. 155-161 ◽

Cited By ~ 8

Author(s):

J. P. Longwell ◽

J. Grobman

Keyword(s):

Thermal Stability ◽

Fossil Fuels ◽

Freezing Point ◽

Pollutant Emissions ◽

Efficient Utilization ◽

Ignition Characteristics ◽

Aviation Turbine Fuel ◽

Engine Components ◽

Combustor Liner ◽

Thermal Stability Of

The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. This paper discusses the effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications.

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Evaluation of the thermal stability of composite powder materials in a plasma jet

NOVYE OGNEUPORY (NEW REFRACTORIES) ◽

10.17073/1683-4518-2021-6-39-43 ◽

2021 ◽

pp. 39-43

Author(s):

I. N. Kravchenko ◽

Yu. A. Kuznetsov ◽

A. L. Galinovskii ◽

S. A. Velichko ◽

P. A. Ionov ◽

...

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Erosion Resistance ◽

Plasma Jet ◽

Operating Conditions ◽

Powder Materials ◽

Gas Flows ◽

Sharp Change ◽

Thermal Stability Of ◽

High Temperature Gas

The results of studies of the thermal stability of materials operating in a plasma jet at high temperatures and a sharp change in thermal loads are presented. It has been proven that the use of plasma generators with the introduction of various powder materials makes it possible to simulate the operating conditions of parts in high-temperature gas flows with heated particles. The effect of the introduced powder materials on the thermal stability of samples prepared by plasma spraying from molybdenum, as well as tungsten and tungsten-based compositions is investigated. An installation is proposed for assessing the thermal stability of composite materials and protective hardening coatings operating under high-temperature gas flows, which makes it possible to determine their erosion resistance.

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An Elastomeric Energy Storage Device for Automotive Engine Restart

Rubber Chemistry and Technology ◽

10.5254/1.3535046 ◽

1980 ◽

Vol 53 (2) ◽

pp. 335-345 ◽

Cited By ~ 1

Author(s):

P. C. Killgoar ◽

R. A. Pett ◽

R. J. Tabar ◽

L. R. Foote

Keyword(s):

Thermal Stability ◽

Mass Production ◽

Adhesive System ◽

Operating Conditions ◽

Storage Device ◽

Design Criteria ◽

Energy Storage Device ◽

Automotive Engine ◽

The Individual ◽

Thermal Stability Of

Abstract An elastomeric spring starter using rubber in shear has been designed. Design criteria have been established and used to develop potential compounds for use in the device. Natural rubber proved to be the elastomer of choice primarily because of its excellent fatigue resistance. To reconcile bonding requirements and requirements for low hysteresis, the individual rings were fabricated from two elastomer compounds. Limitations on the thermal stability of the adhesive system were identified which put constraints on the operating conditions for the starter. A prototype starter has been assembled and installed in a vehicle. This prototype starter provides quiet, rapid starting of the test car. Questions of cost effectiveness, reliability, durability or manufacturing feasibility of this device have not been addressed. The starter was built for experimental purposes only and development of such a concept for mass production has not been explored.

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Thermal stability of beta[sup ʺ]-alumina solid electrolyte under AMTEC operating conditions

10.1063/1.1290958 ◽

2000 ◽

Author(s):

Roger M. Williams

Keyword(s):

Thermal Stability ◽

Solid Electrolyte ◽

Operating Conditions ◽

Thermal Stability Of

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The Ordered Phase Formation in Ti-Al-Ga Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069193 ◽

1970 ◽

Vol 28 ◽

pp. 440-441

Author(s):

Shiro Fujishiro ◽

Harold L. Gegel

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Titanium Alloys ◽

Growth Kinetics ◽

Stoichiometric Composition ◽

Good Potential ◽

Alpha Titanium ◽

Cold Rolled ◽

Kinetics Of ◽

Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

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Microstructure studies of tungsten silicide schottky contacts on Gaas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126445 ◽

1987 ◽

Vol 45 ◽

pp. 328-329

Author(s):

Yih-Cheng Shih ◽

E. L. Wilkie

Keyword(s):

Thermal Stability ◽

Field Effect Transistors ◽

Schottky Contact ◽

Schottky Contacts ◽

Excellent Thermal Stability ◽

Barrier Heights ◽

Gaas Substrates ◽

Film Adhesion ◽

Threshold Voltages ◽

Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

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