Patterning of epitaxial VO2microstructures by a high-temperature lift-off process

2014 ◽  
Vol 1 (4) ◽  
pp. 046302 ◽  
Author(s):  
Tony Yamin ◽  
Tal Havdala ◽  
Amos Sharoni
Keyword(s):  
2004 ◽  
Author(s):  
Medhat A. Toukhy ◽  
PingHung Lu ◽  
Kate Kao ◽  
Robert Plass ◽  
Ching-Hui Chen ◽  
...  
Keyword(s):  

Author(s):  
Wengang Li ◽  
Yinli Xiao ◽  
Yipin Lu ◽  
Zhibo Cao ◽  
Juan Wu

For the purpose of providing the scientific insights to combustion characteristics of spray jet, numerical calculations of reacting and non-reacting spray cases are performed for ECN (engine combustion network) Spray A (n-dodecane spray combustion) which coupled finite chemistry combustion model PaSR and detailed chemical reaction kinetics based on OpenFOAM. The applicability and accuracy of the spray model is verified in the non-reacting spray case, and it is found that the predicted spray characteristics such as the penetration length of liquid and vapor and the mixture fraction are in good agreement with the test results. The two processes of low-temperature reaction and high-temperature ignition experienced by n-dodecane spray ignition are analyzed in reacting spray case, and it is found that the low-temperature reaction continues to exothermic before high-temperature ignition, and continues to proceed stably after high-temperature ignition, which promotes high-temperature ignition and flame stability. Finally, the effects of different fuel injection pressures on ignition delay time and flame lift-off length are studied.


2017 ◽  
Vol 111 (9) ◽  
pp. 091605 ◽  
Author(s):  
Wei Tong ◽  
Lu Qiu ◽  
Jian Jin ◽  
Lidong Sun ◽  
Fei Duan

Author(s):  
Ganesh Subbuswamy ◽  
Xianchang Li ◽  
Kunal Gharat

Film cooling has been successfully used in cooling gas turbine components that are exposed to very high temperature environments. One main disadvantage of using film cooling is the aerodynamic losses associated. To address to the needs of obtaining uniform cooling in the downstream regions, backward injection of coolant has proved to be effective. However, there is a need to understand the aerodynamic behaviors of jet and mainstream flows in order to design effective configurations with this scheme of injecting coolant. In this work, the underlying aerodynamic principles of backward injection are studied numerically. All simulations are conducted with Fluent, a commercial CFD software. Results show that the classical counter rotating vortex found in simple cylindrical holes are not seen in the case of backward injections. Backward injection results in reduced coolant requirements and elimination of complex hole designs to avoid jet lift-off.


Author(s):  
Nilaphai Ob ◽  
Ajrouche Hugo ◽  
Hespel Camille ◽  
Moreau Bruno ◽  
Chanchaona Somchai ◽  
...  

The intermediate fermentation mixture of butanol production, Acetone, Butanol and Ethanol (ABE), is increasinglyconsidered as a new alternative fuel in CI engines due to its physical and chemical properties, which are similar to those of butanol, and its advantages of no additional cost or energy consumption due to butanol separation. In a previous study, the High-Pressure and High-Temperature (HPHT) chamber, called ‘New One Shot Engine” (NOSE), was used to investigate macroscopic spray-combustion parameters by validating Spray-A conditions of the Engine Combustion Network. The present study concerns the spray-combustion characteristics of the ABE mixture (volume ratio 3:6:1), blended with n-dodecane at a volumetric ratio of 20% (ABE20), compared to n-dodecane as reference fuel. The macroscopic spray and combustion parameters were investigated, for non-reactive conditions, in pure Nitrogen and for reactive conditions, in 15% oxygen, at ambient pressure (60 bar), ambient density (22.8 kg/m3) and different ambient temperatures (800 K, 850 K and 900 K). The liquid and vapor spray penetrations were investigated by the Diffused Back Illumination (DBI) and Schlieren techniques in non-reactive conditions. In reactive conditions, the lift-off length was measured by OH* chemiluminescence images at 310 nm. The Schlieren technique was also used to verify the choice of detection criterion. The ignition delay results of the two fuels were compared. It was found that the behavior of the two fuels as a function of temperature was similar even if the liquid length of ABE20 was shorter than that of n-dodecane at all ambient temperatures. On the other hand, no real difference in vapor spray penetration between the two fuels was observed. The vaporization properties and the lower auto-ignition ability of ABE20 led to longer ignition delays and lift-off length.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4852


Author(s):  
Lu Zhang ◽  
Le Zhang ◽  
Ying Wang ◽  
Zhenchuan Yang ◽  
Guizhen Yan

Lift-off has been widely used in microfabrication process. In normal lift-off process, after photolithography and developing, a thin layer of residua will remain on the exposed substrate. To remove the residua, descum and back sputtering are required before metal sputtering. However, because of the high temperature of descum process and high energy induced by ion bombardment during back sputtering, the up inner angle of photoresist will increase in normal lift-off process. The metal films will deposit on the sidewall of the photoresist, and adhere to the substrate even after the photoresist removal. In order to overcome these problems, a lift-off process adopting dual layer photoresist is introduced in this paper, and high quality metallic pattern could be made.


1986 ◽  
Vol 5 (1-4) ◽  
pp. 395-401 ◽  
Author(s):  
P. Buchmann ◽  
V. Graf ◽  
Th.O. Mohr ◽  
P. Vettiger
Keyword(s):  

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