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Design and optimization of a novel electrically controlled high pressure fuel injection system for heavy fuel aircraft piston engine

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Chinese Journal of Aeronautics 2018年第9期31卷 1920-1928页

作者： Ke ZHANG Xudong HUANG Zhifeng XIE Ming ZHOU School of Aerospace Engineering Tsinghua University

The heavy fuel compression ignition engines are widely equipped as aircraft piston engines. The fuel injection system is one of the key technologies that determines the performance of engine. One of the main challenges is to precisely control the injected fuel quantity and flow rate in the presence of pressure fluctuation. This challenge is even more serious for heavy fuel. An original design for electrically controlled high pressure fuel injection system called Multi-Pumppressure-reservoirs fuel injection System(MPS) was demonstrated to reduce the pressure fluctuation and help keep injection stable. MPS was compared with an ordinary high pressure Common Rail fuel injection System(CRS). This work established one-dimensional AMESim and mathematical models for both CRS and MPS to study the effect of different structures and geometric parameters on the pressure fluctuations. The calculations show that the average fuel pressure fluctuation of MPS can be reduced by 57% for the crankshaft speed of 1900 r/min, and the pressure fluctuation before injection reduced by 100%. It is concluded that the pressure performance of MPS is less sensitive to pressure reservoir volume than that of CRS, and there is an opportunity for further volume reduction.

关键词： Aircraft engines AMESim Common rail Fuel injection Mathematical models pressure effects Structural design

Density-functional theory study of the effect of pressure on the elastic properties of CaB_6

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Chinese Physics B 2013年第7期22卷 420-425页

作者：韩晗 Surface Physics Laboratory (National Key Laboratory) Key Laboratory of Computational Physical Sciencesand Department of PhysicsFudan University

Under high pressure, the long believed single-phase material CaB6 was latterly discovered to have a new phase tI56. Based on the density-functional theory, the pressure effects on the structural and elastic properties of CaB6 are obtained. The calculated bulk, shear, and Young’s moduli of the recently synthesized high pressure phase tI56-CaB6 are larger than those of the low pressure phase. Moreover, the high pressure phase of CaB6 has ductile behaviors, and its ductility increases with the increase of pressure. On the contrary, the calculated results indicate that the low pressure phase of CaB6 is brittle. The calculated Debye temperature indicates that the thermal conductivity of CaB6 is not very good. Furthermore, based on the Christoffel equation, the slowness surface of the acoustic waves is obtained.

关键词： density-functional theory elastic properties pressure effects acoustic properties

EXPERIMENTAL STUDY ON THE effects OF AIR ENTRAINMENT ON A PLANE JET DIFFUSION IN A PLUNGE POOL

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Journal of Hydrodynamics 1999年第2期11卷 32-37页

作者： Guo, Yakun Luo, Ming Sichuan univ Chengdu China

Laboratory experimental results about the effects of air entrainment on the jet diffusion in a plunge pool were presented. The results indicate that the air entrainment has little effect on the maximum mean impinging pressure generated by the jet at pool bottom. The maximum fluctuating pressure is increased with the increase of the air entrainment. Air entrainment also reduces jet spreading.

关键词： Air ejectors Energy dissipators Jet engines Jets pressure effects pressure measurement Velocity measurement

Homogeneous catalytic wet air oxidation for the treatment of textile wastewaters

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Journal of Environmental Sciences 2000年第4期12卷 410-415页

作者： Lei, L. Sun, Y. Dept. of Envtl. Science and Engrg. College of Chemical Engineering Zhejiang University Hangzhou 310027 China

An extensive series of experiments was carried out in order to identify suitable catalysts to boost the reaction rate of wet air oxidation of real textile wastewaters at relatively mild temperature and pressure. Experimental results indicated that all catalysts tested in this investigation had shown an impressive increase in the initial COD and TOC removal rate as well as the COD and TOC removal levels in two hours reaction. Among all the catalysts tested, copper salts were more effective than the rest. Anions of the salt solutions also played a role in the catalytic process with nitrate ions having better effect than sulfate ions. Hence copper nitrates were more effective than copper sulfates. It was also found that a mixture of salts with different metals performed better than either of the component single salt alone.

关键词： Catalysis Chemical oxygen demand Copper compounds Low temperature effects Negative ions Nitrates Oxidation pressure effects Rate constants Salts

EXPERIMENTAL STUDY ON THE SECOND-ORDER DIFFRACTION WAVE pressure AND FORCE ON A CIRCULAR CYLINDER UNDER STOKES WAVE ACTION

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Journal of Hydrodynamics 1993年第2期5卷 94-103页

作者： Zhou, Zhi-li Tian, Yong-an Dai, Yi-shan Huang, Wei-li Harbin Shipbuilding Engineering Inst Harbin China

This paper presents the model test to measure the second-order wave pressure and forces on a circular cylinder fixed in Stokes wave with a given draught. The distributions of second-order oscillating and steady wave pressure on the wet surface of the cylinder and second order oscillating wave forces were obtained in this test, but the second-order steady wave force was not able to be measured due to its very small magnitude. The test results also show that third-order wave force may be greater than the second-order force when wave frequencies are high. The experimental results were compared with the corresponding calculation results of Reference [3].

关键词： Cylinders (shapes) Diffraction Fluid structure interaction Force measurement Hydrodynamics Loads (forces) Mathematical models pressure effects

Deuterium cluster jet produced at moderate backing pressures

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Chinese Optics Letters 2006年第5期4卷 249-251页

作者：王红斌葛芳芳刘红杰倪国权杨向东谷渝秋温贤伦周维民王光昶温天舒何颖玲焦春晔张双根王向贤 Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610064 Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900 Department of Science Chongqing UniversityChongqing 400044 Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900 Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900 State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610064

A deuterium cluster jet produced in the supersonic expansion into vacuum of deuterium gas at liquid nitrogen temperature and moderate backing pressures are studied by Rayleigh scattering techniques. The experimental results show that deuterium clusters can be created at moderate gas backing pressures ranging from 8 to 23 bar, and a maximum average cluster size of 350 atoms per cluster is estimated. The temporal evolution of the cluster jet generated at the backing pressure of 20 bar demonstrates a two-plateau structure. The possible mechanism responsible for this structure is discussed. The former plateau with higher average atom and cluster densities is more suitable for the general laser-cluster interaction experiments.

关键词： Deuterium Jets Laser beams pressure effects Rayleigh scattering

Critical Temperature Characteristics of Layered High-Temperature Superconductor Under pressure

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Communications in Theoretical Physics 2009年第4期51卷 761-764页

作者： LIANG Fang-Ying Institute of Science and Technology for OPTO-Electronic Information of Yantai University Yantai 264005 China

We consider a Ginzburg-Landau modified model of layered high-temperature superconductor under pressure. We have theoretically studied the relation between the pressure and the temperature of layered high-temperature superconductor. If the pressure is not a constant, we have a relation of quadratic equation between the pressure and the temperature of layered high-temperature superconductor. In a special case, we find the critical temperature decreases with further increasing pressure. In another special ease, the critical temperature increases with further increasing pressure.

关键词： pressure effects transition temperature variations layered superconductor

Measurements of pressure induced self-broadening and frequency shift coefficients of methane R9 manifold of 2v_3 band

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Chinese Optics Letters 2005年第6期3卷 367-369页

作者：马维光董磊尹王保李霖峰张雷贾锁堂 State key Laboratory of Quantum Optics and Quantum Optics Devices College of Physics and Electronics Engineering Shanxi UniversityTaiyuan 030006

An external-cavity diode laser (ECDL) has been used to investigate pressure-induced self-broadening as well as frequency shift of 2v3 band R9 manifold of methane. A phase sensitivity detection technology has been employed to determine the pressure induced frequency shift coefficient, however, which is obtained by line shape analyses of the recorded absorption spectrum. F1 and F2 unresolved double lines near 6105.626 cm-1 were measured as an object because they are often used to the high sensitivity detection of trace methane. The results show that the self-broadening and pressure induced frequency shift coefficients are 0.0232±0.003 and 0.0055±　0.0007 MHz/Pa, respectively.

关键词： Gas detectors Methane pressure effects Semiconductor lasers

Hydrogen Sensing Property of Lanthanum Complex Fluoride

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Journal of Rare Earths 1993年第2期11卷 115-119页

作者：吴明娒任玉芳 Changchun Institute of Applied Chemistry Academia SinicaChangchun 130022China

Four potentiometer sensor cells have been prepared by using La0.95Pb0.05F2.95 as solid electrolyte(SE) and various materials as electrodes. The sensor cell `Bi(BiF3)|SE|Pt' exhibits the best performance with its 90% response time as short as 75 s to 100 Pa H2 in air at room temperature and with its linear decrease of electromotive force (EMF) with an increase of the logarithm of hydrogen partial pressure in the experimental range. The sensor cell shows weaker response to CO.

关键词： Electric field effects Fluorine compounds Gas sensing electrodes Hydrogen pressure effects Solid electrolytes Thermal effects