Analysis of ignition temperature range and surrogate fuel requirements for GCI engine

Development of Detailed Chemical Kinetic Mechanisms for Ignition/Oxidation of JP-8/Jet-A/JP-7 Fuels

Volume 2: Turbo Expo 2003 ◽

10.1115/gt2003-38932 ◽

2003 ◽

Cited By ~ 10

Author(s):

M. A. Mawid ◽

T. W. Park ◽

B. Sekar ◽

C. A. Arana

Keyword(s):

Chemical Kinetic ◽

Current Status ◽

Fuel Blend ◽

Temperature Oxidation ◽

Temperature Range ◽

Delay Times ◽

Kinetic Mechanisms ◽

Surrogate Fuel ◽

Autoignition Delay ◽

Detailed Chemical

Progress on development and validation of detailed chemical kinetic mechanisms for the U.S. Air Force JP-8 and JP-7 fuels [1] is reported in this article. Two JP-8 surrogate fuel blends were considered. The first JP-8 surrogate blend contained 12 pure hydrocarbon components, which were 15% n-C10H22, 20% n-C12H26, 15% n-C14H30, 10% n-C16H34, 5% i-C8H18, 5% C7H14, 5% C8H16, 5% C8H10, 5% C10H14, 5% C9H12, 5% C10H12 and 5% C11H10 by weight. The second JP-8 surrogate blend contained 4 components, which were 45% n-C12H26, 20% n-C10H22, 25% C10H14, and 10% C7H14 by weight. A five-component surrogate blend for JP-7 was also considered. The JP-7 surrogate blend components were 30% n-C10H22, 30% n-C12H26, 30% C10H20, 5% i-C8H18, and 5% C7H8 by weight. The current status of the JP-8 and JP-7 mechanisms is that they consist of 221 species and 1483 reactions and 205 species and 1438 reactions respectively. Both JP-8 and JP-7 mechanisms were evaluated using a lean fuel-air mixture, over a temperature range of 900–1050 K and for atmospheric pressure conditions by predicting autoignition delay times and comparing them to the available experimental data for Jet-A fuel. The comparisons demonstrated the ability of the 12-component JP-8 surrogate fuel blend to predict the autoignition delay times over a wider range of temperatures than the 4-component JP-8 surrogate fuel blend. The 5-component JP-7 surrogate blend predicted autoignition delay times lower than those of JP-8 blends and Jet-A fuel. The JP-8 and JP-7 mechanisms predictions, however, showed less agreement with the measurements towards the lower end of the temperature range (i.e., less than 900 K). Therefore, low temperature oxidation reactions and the sensitivities of the autoignition delays to reaction rate constants are still needed.

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Defects in ion implanted silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109070 ◽

1978 ◽

Vol 36 (1) ◽

pp. 386-387

Author(s):

J.A. Lambert ◽

P.S. Dobson

Keyword(s):

Defect Structure ◽

Dislocation Loops ◽

Frank Loop ◽

Burgers Vector ◽

Temperature Range ◽

Perfect Dislocation ◽

Contrast Analysis ◽

Image Position ◽

Ion Implanted

The defect structure of ion-implanted silicon, which has been annealed in the temperature range 800°C-1100°C, consists of extrinsic Frank faulted loops and perfect dislocation loops, together with‘rod like’ defects elongated along <110> directions. Various structures have been suggested for the elongated defects and it was argued that an extrinsically faulted Frank loop could undergo partial shear to yield an intrinsically faulted defect having a Burgers vector of 1/6 <411>.This defect has been observed in boron implanted silicon (1015 B+ cm-2 40KeV) and a detailed contrast analysis has confirmed the proposed structure.

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Domain coarsening by grain boundary migration in ordered Ni4Mo

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144279 ◽

1986 ◽

Vol 44 ◽

pp. 560-561

Author(s):

K. Vasudevan ◽

H. P. Kao ◽

C. R. Brooks ◽

E. E. Stansbury

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Short Range ◽

Boundary Migration ◽

Grain Boundary Migration ◽

Rapid Cooling ◽

Temperature Range ◽

Fee Structure ◽

Domain Coarsening ◽

Boundary Reaction

The Ni4Mo alloy has a short-range ordered fee structure (α) above 868°C, but transforms below this temperature to an ordered bet structure (β) by rearrangement of atoms on the fee lattice. The disordered α, retained by rapid cooling, can be ordered by appropriate aging below 868°C. Initially, very fine β domains in six different but crystallographically related variants form and grow in size on further aging. However, in the temperature range 600-775°C, a coarsening reaction begins at the former α grain boundaries and the alloy also coarsens by this mechanism. The purpose of this paper is to report on TEM observations showing the characteristics of this grain boundary reaction.

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The reaction of amorphous Ni-Nb films with Si in the presence of a native SiO2 layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176459 ◽

1990 ◽

Vol 48 (4) ◽

pp. 664-665

Author(s):

N. Rozhanski ◽

A. Barg

Keyword(s):

High Temperature ◽

Crystallization Temperature ◽

Diffusion Barriers ◽

Sio2 Layer ◽

Si Substrate ◽

Cross Sectional ◽

Plan View ◽

Temperature Range ◽

Sputter Deposited

Amorphous Ni-Nb alloys are of potential interest as diffusion barriers for high temperature metallization for VLSI. In the present work amorphous Ni-Nb films were sputter deposited on Si(100) and their interaction with a substrate was studied in the temperature range (200-700)°C. The crystallization of films was observed on the plan-view specimens heated in-situ in Philips-400ST microscope. Cross-sectional objects were prepared to study the structure of interfaces.The crystallization temperature of Ni5 0 Ni5 0 and Ni8 0 Nb2 0 films was found to be equal to 675°C and 525°C correspondingly. The crystallization of Ni5 0 Ni5 0 films is followed by the formation of Ni6Nb7 and Ni3Nb nucleus. Ni8 0Nb2 0 films crystallise with the formation of Ni and Ni3Nb crystals. No interaction of both films with Si substrate was observed on plan-view specimens up to 700°C, that is due to the barrier action of the native SiO2 layer.

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A Transmission Electron Microscopical Investigation of Phase Transformations in TiNi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001446 ◽

1980 ◽

Vol 38 ◽

pp. 340-341

Author(s):

P. Moine ◽

G. M. Michal ◽

R. Sinclair

Keyword(s):

Electron Microscopy ◽

Phase Transformations ◽

Applied Stress ◽

Structural Changes ◽

Microscopical Investigation ◽

Temperature Range ◽

Transmission Electron ◽

Electron Microscopical ◽

Diffraction Effects ◽

Microscopy Images

Premartensitic effects in near equiatomic TiNi have been pointed out by several authors(1-5). These include anomalous contrast in electron microscopy images (mottling, striations, etc. ),diffraction effects(diffuse streaks, extra reflections, etc.), a resistivity peak above Ms (temperature at which a perceptible amount of martensite is formed without applied stress). However the structural changes occuring in this temperature range are not well understood. The purpose of this study is to clarify these phenomena.

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