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Science China(Technological Sciences) 2010年第10期53卷 2699-2707页

作者： HU HaiYang1 & WANG Qiang2 1 China Academy of Aerospace Aerodynamics, Beijing 100074, China 2 School of Jet Propulsion, Beihang University, Beijing 100191, China China Academy of Aerospace Aerodynamics Beijing China School of Jet Propulsion Beihang University Beijing China

A coupled model among flow field,solid temperature,species concentration and gas radiation,which was based on statistical narrow-band correlated-k model,was employed to predict the infrared radiations from hot exhausting nozzles. The parameters of narrow-band model were deduced from HITEMP line-by-line database. Several methods to increase computational efficiency and to save computational resources were employed,thus all the complicated computations could be operated on a personal computer. The predictions for three cases have been conducted to validate the accuracy of the methods mentioned above,including the temperature distribution of a water-cooling nozzle in rocket engines,the carbon dioxide absorptivity at the wavelength of 4.3 micron and the infrared radiation of a cylindrical furnace. Finally,the aerothermodynamic and infrared characteristics of two nozzles were predicted. It was shown that the infrared radiation intensity of chevron ejecting nozzle were obviously smaller than that of common axisymmetric convergent-divergent nozzle.

关键词： infrared radiation numerical simulation exhausting nozzles coupled model

Physical model of fluid flow characteristics in RH-TOP vacuum refining process

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 483-489页

作者： Lu Lin Yan-ping Bao Feng Yue Li-qiang Zhang Hong-lin Ou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

To understand the characteristic of circulation flow rate in 250-t RH-TOP vacuum refining process, the 1：4 water model test was established through the bubble behavior and gas holdup in the up-leg to investigate the effects of different processes and equipment parame- ters on the RH circulation flow rate. With the increases of lifting gas flow rate, liffing bubble travel, and the internal diameter of the up-leg, and the decrease of nozzle diameter, the work done by bubble floatage and the circulation flow rate increase. The expression of circulation flow rate was derived fi＂om the regression analysis of experiment data. Meanwhile, the influences of vacuum chamber pressure and nozzle blockage situation on the circulation flow rate were discussed in detail by the bubble behavior and gas holdup in the up-leg. It is necessary to maintain a certain vacuum chamber liquid level in the molten steel circulation flow. Compared with a nozzle with symmetrical blockage in the up-leg, when a nozzle with non-symmetrical blockage is applied, the lifting gas distribution is non-uniform, causing a great effect on the molten steel circulation flow and making the circulation flow drop largely.

关键词： steelmaking refining molten steel flow characteristic bubbles nozzles

NUMERICAL SIMULATION AND MEASUREMENT OF TURBULENT JET WITH FREE SURFACE

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Journal of Hydrodynamics 1999年第1期11卷 73-78页

作者： Zhan, Dexin Wang, Xianfu Xiong, Aokui Wuhan Transportation Univ Wuhan China

Numerical simulation of submerged turbulent jet was presented by a pseudo-compressibility method. Reynolds averaged Navier-Stokes equations were confined by a k-Ε model. Based on the experimental data of Reynolds stress, a modified form of the k-Ε model was proposed. The boundary location of free surface was approximated by the linearized free surface conditions and free surface location was obtained by solving the free surface equation. The third-order upwind difference scheme was adopted in the derivative term of wave elevation. The experiments were conducted in water channel and maneuvering pool. The jet flow velocity distribution for different depths of jet nozzle were measured. A mean velocity distribution formula was presented.

关键词： Approximation theory Finite difference method Flow of water nozzles Numerical analysis Turbulent flow Wave effects

Transient heat transfer characteristics of air-array-jet impingement with different nozzle arrangements on high-tempera-ture flat plate in small jet-to-plate distance

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排灌机械工程学报 2020年第3期38卷 277-284页

作者： LI Meixiang ZHU Keqian XIE Yu CAI Tingting YUAN Ningyi DING Jianning School of Mechanical Engineering Changzhou UniversityChangzhouJiangsu 213164China Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering ChangzhouJiangsu 213164China Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology ChangzhouJiangsu 213164China School of Mechanical Engineering Jiangsu UniversityZhenjiangJiangsu 212013China

Numerical studies on transient heat transfer characteristics of air-array-jet impingement with a small jet-to-plate distance and a large temperature difference between nozzles and plate were presented.The dimensionless jet-to-plate distance(H/D)was 0.2,and non-dimensional nozzle-to-nozzle spacing(S/D)was 3,4,5 and 6,respectively.It is found that the quenching time is shortened at a constant total mass flow at air jet inlet m·(m·=218.21 kg/h),and the heat transfer uniformity is deterio-rated as S/D increases.However,the adding reversed-flow nozzles can shorten the quenching time of the glass plate considerably with a modest change in the heat transfer uniformity.The results at variable m·are the same as those at a fixed m·.Furthermore,the parity and arrangement of nozzles are also discussed,It is found that an odd number of nozzles is more beneficial for transient heat transfer.Based on these results,an appropriate proposal for ultra-thin glass tempering process is presented.

关键词： glass tempering low jet-to-plate distances array jet impingement nozzles arrangement transient heat transfer

Aircraft Engine Design, Second Edition 2nd ed.

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Experiments with Forming Coated Sheets with Plasma-Chemical Pretreatment of the Surface

丛书名： AIAA Education Series

2002年

作者： Jack D. Mattingly William H. Heiser David T. Pratt

ISBN: (数字)9781600861444

ISBN: (纸本)9781563475382

Winner of the Summerfield Book Award! The text presents a complete and realistic aircraft engine design experience. From the request for proposal for a new aircraft to the final engine layout, the book provides the concepts and procedures required for the entire process. It is a significantly expanded and modernized version of the best-selling first edition that emphasizes recent developments impacting engine design such as theta break-throttle ratio, life management, controls, and stealth. The key steps of the process are detailed in 10 chapters that encompass aircraft constraint analysis, aircraft mission analysis, engine parametric (design point) analysis, engine performance (off-design) analysis, engine installation drag and sizing, and the design of inlets, fans, compressors, main combustors, turbines, afterburners, and exhaust nozzles.The AEDsys software that accompanies the text provides comprehensive computational support for every design step. The software has been carefully integrated with the text to enhance both the learning process and productivity, and allows effortless transfer between British engineering and SI units. The AEDsys software is furnished on CD-ROM and runs on the Windows operating system. A user’s manual is provided with the software, along with the complete data files used for the Air-to-Air Fighter and Global Range Airlifter design examples of the book.

关键词： Aircraft Engines Combustion Chambers Combustors nozzles Propulsion and Power Rocket Engine Rocketry

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畅想之星图书光盘版（南通市图书馆镜像）

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Journal of Surface Engineered Materials and Advanced Technology 2016年第3期6卷 118-124页

作者： Emil Schwarzer Milan Dvořák BUT Faculty of Mechanical Engineering IMT Brno Czech Republic

The article used new experimental equipment for effective testing of adhesion coatings on the sheets. Testing was performed in jig by bending roller with selected radius. In the context of experiments a multi-jet system was used. The aim of my previous publications and even this article is to achieve that by using of multi-jet plasma system, samples were achieved that will not be damaged coating after the bending. Specific coats on the sheets have been optimized composition of the plasma so that its result was the maximum adhesion of the coating to the steel base of samples. Results of experiments are presented in article. The article focuses on the tensile test and the result of the tensile test. All important values of tensile tests are published in this article. For example: elongation A50, Ag, tensile strength Rm, and yield strength Rp0.2. Results with values of tensile tests are also presented in this article. Selected coated steel samples were photographed in the clamped in jig on the tension device. Group selected samples were divided by the applied coating. First, the basecoat, the final coat and coat were treated with a multi-jet plasma system. From a previous publication graphs show the dependence of the strength on elongation of a sample. Further research will be focused on selected coated samples, where samples are etched onto the surface of a network and are bent in a special jig in range bending radius R11 to R35. After bending, the samples are examined at a special optical device and are evaluated deformation circles in straight and bent part of the samples.

关键词： nozzles Bending Multi-Jet Plasma System Flow Tensile Tests Coating

Numerical Simulation of Thermal Contact Resistance between Divergence Cone Interface on Composite Nozzle

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Numerical Simulation of Thermal Contact Resistance between D...

Thermodynamics of Efflux Process of Liquids and Gases

2010亚太航空航天技术研讨会

作者： Zheng Xiaoya~*,Zhang Duo School of Astronautics,Northwestern Polytechnic University,Xi’an,710072,China

Because the mechanism of thermal contact resistance is complex,it is entirely neglected in thermal structure analysis of composite nozzle.The research object is a typical composite nozzle which has two layered divergence cone.The adhesive is carbonized when the temperature exceeds 200℃and the interface on two layered divergence cone is full of macromolecule gas.Therefore,thermal contact resistance should be considered.Based on Galerkin theory,the thermodynamic finite formulations of axisymmetrical thermal contact resistance element are built.Numerical value of thermal contact resistance is estimated through experimental data by home code for transient heat transfer.Simulation results show that thermal contact resistance has strong influence on heat transfer of two layered divergence cone.Considering from the heat transfer,two layered divergence cone structure have an adiabatic effect on outer case.In thermal structure analysis,the calculated temperature on nozzle wall compares favorably with experimental data when the numerical value of thermal contact resistance is approximate 0.025m·℃/W.The reverse method of thermal contact resistance provides reference for precise heat transfer on composite nozzle.

关键词： nozzles thermal contact resistance heal transfer convective heat transfer thermodynamic finite formulation

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Journal of Power and Energy Engineering 2015年第5期3卷 71-74页

作者： E. А. Mikaelian Saif A. Mouhammad Gubkin Russian State University of Oil and Gas Moscow Russia Physics Department Faculty of Science Taif University Taif Kingdom of Saudi Arabia

The main objective of this work is to obtain the calculated ratio of efflux processes for liquids, vapors, gases on the basis of the developed mathematical model, which allows to determine the characteristics of the channel profiles nozzles and diffusers, to solve a number of subsequent applications for analysis modes. On the basis of the calculated ratios are equations of the first law of thermodynamics for the flow of liquids and gases. The obtained calculated ratios are extended for the case of the efflux of compressible liquids, vapors and gases and as a special case, for incompressible liquids. The characteristics of the critical efflux regime liquids, which allows to determine the linear and the mass efflux rate of the critical regime and the calculated characteristics of the channel profiles nozzles and diffusers, Laval nozzles for different modes of operation are obtained.

关键词： Thermodynamics Efflux Compressible Incompressible Liquids Diffusers nozzles

STUDY ON THE EFFECT OF NOZZLE MATERIALS AND SHAPE TO PRESSURE RISE DURING INTERRUPTING DUTY OF THE SELF-BLAST HIGH-VOLTAGE CIRCUIT BREAKER

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STUDY ON THE EFFECT OF NOZZLE MATERIALS AND SHAPE TO PRESSUR...

The ⅪⅩ International Conference on Gas Discharges and Their Applications

作者： H.S.SOHN M.J.HA J.J.CHAE H.S.JUNG C.H.YEO J.H.KIM Power & Industrial Systems R&D Center Hyosung CorporationAnyang-siGyeonggi-doKorea Power & Industrial Systems R&D Center Hyosung CorporationChangwon-siGyeongsangnamdoKorea

ISBN: (纸本)9771003651221

＜正＞Self-blast circuit breakers utilize the energy dissipated by the arc itself to create the required conditions for arc quenching during the current zero.During the high current phase,the arc energy induces ablation from the PTFE nozzle. In this phenomenon,the ablated nozzle vapor contributes an essential role to build-up the pressure in the thermal chamber.To investigate an effect of nozzle materials and shape,we measured a pressure with a sensor equipped in the thermal chamber while varying a nozzle materials and shape.In this paper,the measured pressure values are compared with the results obtained from computational fluid dynamics （CFD）.The actual high-voltage circuit breakers were used in the experiments.

关键词： nozzles RISE Pressure circuit breakers Tea high voltage circuit breakers arc energy current zero Materials

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开普勒问题的另几种推导

河南广播电视大学学报 1996年第1期11卷 28-,38页

作者：白学义山西广播电视大学

开普勒问题的另几种推导白学义研究一质点在场力和质点到某一白定点的距离ｈｉＶ＄ｈｙ．Ｆｉ’。ｔｇｕｈｆｋ“ｇｈｉ４ｇｈ，ｉｆ＃，－４～ｌ‘ＩＥｉｔ‘ｇ开普勒问题。在有心力作用下。通常求解开普勒问题是根据角动量守恒并作变... 详细信息

开普勒问题的另几种推导白学义研究一质点在场力和质点到某一白定点的距离ｈｉＶ＄ｈｙ．Ｆｉ’。ｔｇｕｈｆｋ“ｇｈｉ４ｇｈ，ｉｆ＃，－４～ｌ‘ＩＥｉｔ‘ｇ开普勒问题。在有心力作用下。通常求解开普勒问题是根据角动量守恒并作变换。Ｉ一上ｕ而得出个易于求解的微分...

关键词： Jet nozzles Vector fields Numerical computation