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1.
Densities of N, H, and NH active species have been detected by laser-induced fluorescence (LIF) in N2-xH2 dc flowing discharges. A peak value of N atom densities far x = 0.2–0.5% and a plateau value of H atom densities between x = 1% and 90% in post-discharge conditions (0.05 sec, p = 2 torr) has been found. Comparison between LIF measurements of N atoms and the trend of the N2(B, v = II) population shows that the emission from this state can be used for monitoring N atoms. The NH radical has only been detected inside the discharge region.On leave from Instituto Tecnológico de Aeronáutica, CNPq, Brazil. 相似文献
2.
Graham J Weir 《Transport in Porous Media》1991,6(5-6):501-517
The two phase flow equations frequently used in geothermal engineering ignore capillary pressure, which results in a singular system of equations. Analysis of these equations reveals three mechanisms for altering saturation: local boiling, the spatial dependence of flowing enthalpy due to the convective transport of fluid, and counterflow. A scalar function is associated with each of these three mechanims. At each point in space, flows are essentially two dimensional, with gravity establishing a vertical hierarchy, in that volumetric, energy and mass fluxes can never point below a lower member in this triple. With increasing liquid saturation, the characteristics associated with the saturation equation move up from below this grouping of directions, and eventually may even point above volumetric fluxes. Finally, weak shocks and the associated entropy condition are considered. The characteristics of the saturation equation coincide with the velocity of extremely weak shocks, and saturation increases with the passage of a weak shock, provided the magnitude of the characteristic speed increases with saturation.Notation Cl
liquid heat capacity
- Cm
rock heat capacity
- Cv
vapour heat capacity
- G
counterflow energy flux
- h
flowing enthalpy
- hl
liquid enthalpy
- hv
vapour enthalpy
-
k
permeability
- k
downward vector
- P
pressure
- S
liquid saturation
- T
temperature
- dT/dP
derivative at saturation
- z
vertical coordinate
- l
liquid viscosity
- v
vapour viscosity
- Pl
liquid density
- m
rock density
- v
vapour density
-
porosity 相似文献
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油井流入动态是油井举升优化设计的基础 ,目前国内外研究油井流入动态的方法有多种 ,但是各有其不足和局限性 .为此利用模拟退火方法进行油井流入动态方法研究 .与以往的近似算法相比 ,该方法不需要将单相流和多相流分开讨论 ,且无任何假设条件 ,适用范围广 ;通过实例 ,把模拟退火的预测的产量结果与利用 Vogel方程所预测的产量结果进行比较和误差分析 ,结果表明 ,该算法的误差是非常小的 .因此 ,利用该算法研究油井流入动态非常可行 . 相似文献
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Determination of N and O‐atoms and N2 (A) Metastable Molecule Densities in the Afterglows of N2‐H2, Ar‐N2‐H2 and Ar‐N2‐O2 Microwave Discharges
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Early afterglows of N2‐H2, Ar‐N2‐H2 and Ar‐N2‐O2 flowing microwave discharges are characterized by optical emission spectroscopy. The N and O atoms and the N2 (A) metastable molecule densities are determined by optical emission spectroscopy after calibration by NO titration for N and O‐atoms and measurements of NO and N2 band intensities. If an uncertainty of 30% is estimated on N‐atomic density, an inaccuracy of one order of magnitude is obtained on the O and N2 (A) densities. In N2‐(0.05‐2.5%)H2 and Ar‐(1‐50%)N2‐(0.05‐2.5%) H2 gas mixtures, the O‐atoms are coming from O2 impurities in the discharge. Concentrations of N and O‐atoms and of N2 (A) densities are compared to the ones obtained in Ar‐(5‐50%)N2‐(0.2‐2.5%) O2 gas mixtures in which a controlled amount of O2 is added. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
8.
本文介绍了一种大画幅纹影成像技本,应用该技术,显示了高超音速流场中锥体边界层转捩。将所得到的纹影图象在显微密度计图象处理系统中进行处理与测量,并结合纹影法原理进行了分析计算,得到了边界层诸截面相对密度变化曲线以及边界层转捩位置等实验结果,该结果与有关气动理论和实践结果进行了比较。 相似文献
9.
Affinity genetic algorithm 总被引:1,自引:0,他引:1
Based on some phenomena from human society and nature, we propose a binary affinity genetic algorithm (aGA) by adopting the
following strategies: the population is adaptively updated to avoid stagnation; the newly generated individuals will be ensured
to survive for some generations in order for them to have time to show their good genes; new individuals and the old ones
are balanced to have the advantages of both. In order to quantitatively analyze the selective pressure, the concept of selection degree and a simple linear control equation are introduced. We can maintain the diversity of the evolutionary population by controlling
the value of the selection degree. Performance of aGA is further enhanced by incorporating local search strategies.
Partially supported by a National Key Basic Research Project of China and by a USA NSF grant CCR-0201253. 相似文献
10.
战略导弹研制风险分析的仿真技术 总被引:2,自引:0,他引:2
本文以战略导弹研制风险分析为背景,对随机网络数据仿真技术原理进行了探讨,分析了曾广泛应用的仿真软件VERTSLAM等的不足,并提出了改进方法,文中给出一种含信息流多层次综合网络仿真的构模框架,并用该构模框架对战略导弹风险分析的仿真模型作了研究。 相似文献