Abstract:Based on dimethyl ether(DME) engine experiments, a turbulent combustion model was developed to study the combustion characteristics of DME engine. It consisted of two sections. First, the correlation of DME thermal properties to temperature are required for numerical simulation of DME spray and combustion process, but cannot be obtained instantly through measurement. So molecule theory was applied here to estimate the correlation of the DME thermal properties to temperature, including latent enthalpy, surface tension, thermal conductivity and diffusion coefficient. And other DME thermal properties measured by experiments, including vapor pressure and viscosity coefficient, are also collected here. Then the combustion model was developed. The model took into account the influence of turbulence on combustion by coherent flamelet model(CFM) in addition to the original chemical kinetic model, so closer to the experiments and can be applied to the qualitative analysis of DME engine combustion. Numerical simulation indicated that, in engine condition DME spray has short tip penetration than diesel oil, with almost no wall impingement occurring. The upper edge of spray near the nozzle ignite first for the appropriate fuel concentration and higher temperature. In diffusion combustion the combustion is slow and lasts long for the slow air-fuel mixture formation. The results of numerical simulation are in good agreement with experiments.

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	1. Thermal Properties and Combustion Modeling of Dimethyl Ether
	Longbao Zhou
	Dynamic and Electronic Engineering 21 December 2005
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	Abstract:Based on dimethyl ether(DME) engine experiments, a turbulent combustion model was developed to study the combustion characteristics of DME engine. It consisted of two sections. First, the correlation of DME thermal properties to temperature are required for numerical simulation of DME spray and combustion process, but cannot be obtained instantly through measurement. So molecule theory was applied here to estimate the correlation of the DME thermal properties to temperature, including latent enthalpy, surface tension, thermal conductivity and diffusion coefficient. And other DME thermal properties measured by experiments, including vapor pressure and viscosity coefficient, are also collected here. Then the combustion model was developed. The model took into account the influence of turbulence on combustion by coherent flamelet model(CFM) in addition to the original chemical kinetic model, so closer to the experiments and can be applied to the qualitative analysis of DME engine combustion. Numerical simulation indicated that, in engine condition DME spray has short tip penetration than diesel oil, with almost no wall impingement occurring. The upper edge of spray near the nozzle ignite first for the appropriate fuel concentration and higher temperature. In diffusion combustion the combustion is slow and lasts long for the slow air-fuel mixture formation. The results of numerical simulation are in good agreement with experiments.
	TO cite this article:Longbao Zhou. Thermal Properties and Combustion Modeling of Dimethyl Ether[OL].[21 December 2005] http://en.paper.edu.cn/en_releasepaper/content/4519


	2. Developments in Reverse Brayton Cycle Cryocooler
	Hou Y ,Zhao H L,Chen C Z,Xiong L Y
	Dynamic and Electronic Engineering 20 December 2005
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	Abstract:As one of the primary methods of cryogenic refrigeration, reverse Brayton cycle cryocooler, which includes high-speed turbine using gas bearing and compact heat exchanger, has many advantages such as long-life, high reliability and efficiency. In this paper general aspects of reverse Brayton cycle cryocooler in China are introduced, such as its application in the space simulation program, mechanical cryocooler for lower temperature space applications. The main design parameters and operating performance of cryocoolers are presented in this paper.
	TO cite this article:Hou Y ,Zhao H L,Chen C Z, et al. Developments in Reverse Brayton Cycle Cryocooler[OL].[20 December 2005] http://en.paper.edu.cn/en_releasepaper/content/4499

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	3. Fused method of fault diagnosis for analog circuits
	Tan Yanghong,He Yigang,Ye Jiazhuo,Chen Wuli
	Dynamic and Electronic Engineering 29 November 2005
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	Abstract:A fused fault diagnosis method based on wavelet packet decomposition of voltages of test nodes and current signals of terminals stimulated is proposed in the paper. For the faults difficult to detect merely from voltages of test nodes, the current signals of the terminals which contain sufficient information with various faults are fused with the sampled node voltages of the circuit stimulated by the sources selected according to the principles proposed to make up for the insufficiency of the node voltages resulting in maximization feature vectors and correctly identifying the fuzzy sets of faults. So higher correct classification to the faults of circuits is obtained.
	TO cite this article:Tan Yanghong,He Yigang,Ye Jiazhuo, et al. Fused method of fault diagnosis for analog circuits[OL].[29 November 2005] http://en.paper.edu.cn/en_releasepaper/content/3839


	4. Calculation of the Shielding Effectiveness of Metallic Wire Structure Using NEC
	Gao Changzheng,Li Lin ,Cui Xiang,Zhao Zhibin
	Dynamic and Electronic Engineering 28 November 2005
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	Abstract:After comparing the NEC software’s results with other references’, the software’s validity in calculating the shielding effectiveness (SE) of complex metallic wire structure is verified. So the SE for an incident electromagnetic wave of the structure built with reinforcing wire mesh can be discussed at the base of the results computed by NEC. Several modes built with reinforcing wire mesh were computed by NEC in the paper and the results show that reinforcing wire mesh has good SE for electromagnetic wave while its SE is determined by many factors such as the frequency of the incident wave, wire grid size, wire radius etc. Some conclusions are useful for the EMP shielding, relay-cell design in substation and so on.
	TO cite this article:Gao Changzheng,Li Lin ,Cui Xiang, et al. Calculation of the Shielding Effectiveness of Metallic Wire Structure Using NEC[OL].[28 November 2005] http://en.paper.edu.cn/en_releasepaper/content/3797


	5. Experimental studies of heat transfer enhancement
	Ye Xiang,Huang Suyi,Li Zhongzhou
	Dynamic and Electronic Engineering 13 October 2005
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	Abstract:With the rapid development of nanometer technology, researchers have gradually applied the new and advanced technology to the traditional area of Energy & Power. A new method of enhancing heat transfer of the heating section of a two—phase closed thermosiphon has been proposed .And, theoretical and experimental studies have been carried out of the performance of the heat transfer enhancement by adding a proper amount of nanoparticles to the thermosiphon with water as the working fluid. Compared with the ordinary thermosiphon, results indicate that this heat pipes posses such advantages as good startup, lower tube wall temperature, and its heat transfer coefficient is increased by 47～96%, heat flux is increased by 7.6～15% in the range of the experiment. The performance of the heat transfer relates to the diameter and the volume fraction of nanoparticle. This new enhancing method is simple and easy to apply in industry.
	TO cite this article:Ye Xiang,Huang Suyi,Li Zhongzhou. Experimental studies of heat transfer enhancement[OL].[13 October 2005] http://en.paper.edu.cn/en_releasepaper/content/3237


	6. Experimental and Numerical Study on the Characteristics of Liquid Phase LPG and Diesel Fuel Sprays
	Xiao Helin ,Zhang Yusheng
	Dynamic and Electronic Engineering 04 August 2005
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	Abstract:his paper presents a comparison study on the spray characteristics with different fuels and different fuel injection parameters. Both experimental and numerical studies were employed in investigating the macroscopic spray structure and the spray characteristics of liquid-phase LPG or diesel/LPG blended fuel injection from high-pressure injectors. The experimental work was conducted on a high-pressure constant volume vessel with high-speed photography. Experimental results show that the spray tip penetration of LPG is shorter than that of the diesel fuel, and the spray cone angle of the LPG is also smaller than that of the diesel fuel at the same injection conditions because LPG has better evaporation and atomization. Based on the computation of characteristics of LPG and diesel fuel spray using KIVA-3V2 and KH-RT breakup model, it is found that the spray tip penetrations at the initial injection stage agree well between numerical and experimental results. There is a difference between
	TO cite this article:Xiao Helin ,Zhang Yusheng . Experimental and Numerical Study on the Characteristics of Liquid Phase LPG and Diesel Fuel Sprays[OL].[ 4 August 2005] http://en.paper.edu.cn/en_releasepaper/content/2602


	7. Determination and Study on Thermo-physical Properties of Graphitized Cathode Carbon Material for Aluminum Reduction Cell
	Chang-hong WANG,Jie-min ZHOU
	Dynamic and Electronic Engineering 20 June 2005
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	Abstract:In this research, a transient experimental system was designed to determine the thermo-physical properties of the graphitized cathode material for aluminum reduction cell by employing modern electrical facilities and data acquisition apparatus, according to the experimental modeling and the characteristic of graphitized cathode carbon. The periodic heat flow was recognized by the two thermocouples as a sinus temperature variation with decreasing amplitude and increasing phase lag when the heat wave propagated through the specimen. The thermal diffusivity can be calculated directly by processing experimental data, and then the thermal conductivity can be obtained with relation to thermal diffusivity if the specific heat and the density are known. The method and the instrument are applicable in the temperature 20~300℃. The research on the method and the measuring system will pave the way to obtain the feasible thermo-physical properties data.
	TO cite this article:Chang-hong WANG,Jie-min ZHOU. Determination and Study on Thermo-physical Properties of Graphitized Cathode Carbon Material for Aluminum Reduction Cell[OL].[20 June 2005] http://en.paper.edu.cn/en_releasepaper/content/2229


	8. Automatic Classification and Analysis of the Characteristic Parameters for Power Quality Disturbances
	Yonghai Xu,Xiangning Xiao
	Dynamic and Electronic Engineering 21 March 2005
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	Abstract:his paper develops an approach to detect and classify power quality disturbance waveforms as well the analysis of the corresponding characteristic parameters using a novel combination of d-q conversion, artificial neural networks, the point to point comparison of ideal voltage with disturbed voltage and wavelet transform. From the results of the d-q conversion through the fictitious three-phase voltages, the classification of voltage sags, swell and interruption is realized. For other disturbances, feature extraction is carried out through the analysis of the results of the d-q conversion, and then artificial neural networks are used for the automatic classification. For the classified disturbances, the corresponding characteristic parameters can be obtained through the analysis of the results of the d-q conversion, the point to point comparison of ideal voltage with disturbed voltage and wavelet transform. Simulation results show that the proposed approach has good performance in val
	TO cite this article:Yonghai Xu,Xiangning Xiao. Automatic Classification and Analysis of the Characteristic Parameters for Power Quality Disturbances[OL].[21 March 2005] http://en.paper.edu.cn/en_releasepaper/content/1734


	9. Simulation on the Arc Plasma Behavior in Low Voltage Circuit Breaker
	Wang Qian
	Dynamic and Electronic Engineering 03 March 2005
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	Abstract:Taking into account the properties of the arc plasma and the electromagnetic, heat and radiative phenomena, commercial computational fluid dynamics software PHOENICS has been adapted and modified to develop the three-dimensional magneto-hydrodynamic (MHD) model of arc in a low voltage circuit breaker. The effects of the arc ignition location, venting size and gassing material on arc behavior are investigated. The analysis of the results show that the arc velocity accelerates with the increase of the distance between arc ignition location and of the venting size, and the existence of the gassing material benefits to improve the arc voltage and reduce the arc temperature.
	TO cite this article:Wang Qian. Simulation on the Arc Plasma Behavior in Low Voltage Circuit Breaker[OL].[ 3 March 2005] http://en.paper.edu.cn/en_releasepaper/content/1632


	10. A Study on Combustion and Emission Characteristics of Small DI Diesel Engine Fuelled with Dimethyl Ether
	Zhang Yusheng ,Mo Chunlan,Zhang Huiya,Lu Yihong,LU Yihong
	Dynamic and Electronic Engineering 05 February 2005
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	Abstract:n investigation has been carried out to evaluate the application feasibility of dimethyl ether(DME) as an alternative fuel using a small direct-injection diesel engine. The fraction of the fuel leakage from the fuel pump plunger pinion to the supplied fuel is determined by the fuel injection experiment under engine motored conditions. The effects of parameters such as engine load, advanced angle of fuel injection, nozzle opening pressure, exhaust valve open angle and DME fuelling rate on engine performance and exhaust emissions are investigated. The test results show that the performance and exhaust emission characteristics of DME are superior when compared to the original diesel engine. The experimental results demonstrate that the DME fueled engine should have an appropriate nozzle opening pressure and advanced angle of fuel injection. Retarded opening of the exhaust valve is found to result in a decrease in oxides of nitrogen emission. In this paper simulation of the auto-ignition
	TO cite this article:Zhang Yusheng ,Mo Chunlan,Zhang Huiya,Lu Yihong, et al. A Study on Combustion and Emission Characteristics of Small DI Diesel Engine Fuelled with Dimethyl Ether[OL].[ 5 February 2005] http://en.paper.edu.cn/en_releasepaper/content/1543

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