Design of Balanced Reactor Welded with Water-Cooled Aluminum Busbars

A new process of welding aluminum water-cooled busbars is proposed, It can not only reduce the weight and cost, but also improve the dynamic and thermal stability. Furthermore~ both finite element method analysis and a prototype test testify the advantages of the design which is not limited by load current and provides a new approach for water-cooled reactors.

Analysis and optimization of heat loss for water-cooled furnace roller

A heat transfer model of furnace roller cooling process was established based on analysis of furnace roller＇s structure. The complicated model was solved with iteration planning algorithm based on Newton search. The model is proved logical and credible by comparing calculated results and measured data. Then, the relationship between water flow velocity, inlet water temperature, furnace temperature and roller cross section temperature, outlet water temperature, water temperature rise, cooling water heat absorption was studied. The conclusions and recommendations are mainly as follows： l） Cooling water temperature rise decreases with the increase of water flow velocity, but it has small relationship with inlet water temperature; 2） In order to get little water scale, inlet water temperature should be controlled below 30 ℃. 3） The cooling water flow velocity should be greater than critical velocity. The critical velocity is 0.07 m/s and water flow velocity should be controlled within 0.4-0.8 m/s. Within this velocity range, water cooling efficiency is high and water temperature rise is little. If cooling water velocity increases again, heat loss will increase, leading to energy wasting.

Numerical Simulation on Subcooled Boiling Heat Transfer Characteristics of Water-Cooled W/Cu Divertors

In order to realize safe and stable operation of a water-cooled W/Cu divertor under high heating condition,the exact knowledge of its subcooled boiling heat transfer characteristics under different design parameters is crucial.In this paper,subcooled boiling heat transfer in a water-cooled W/Cu divertor was numerically investigated based on computational fluid dynamic（CFD）.The boiling heat transfer was simulated based on the Euler homogeneous phase model,and local differences of liquid physical properties were considered under one-sided high heating conditions.The calculated wall temperature was in good agreement with experimental results,with the maximum error of 5%only.On this basis,the void fraction distribution,flow field and heat transfer coefficient（HTC）distribution were obtained.The effects of heat flux,inlet velocity and inlet temperature on temperature distribution and pressure drop of a water-cooled W/Cu divertor were also investigated.These results provide a valuable reference for the thermal-hydraulic design of a water-cooled W/Cu divertor.

Preparation of Al-Zn-Mg-Cu alloy semisolid slurry through a water-cooled serpentine pouring channel

The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water flow rate on the microstructure of the semisolid Al-Zn-Mg-Cu alloy slurry were investigated. The results show that the semisolid Al-Zn-Mg-Cu alloy slurry with satisfactory quality can be generated by the WSPC when the pouring temperature is in the range between 680 ℃ and 700 ℃. At a given pouring temperature, the average grain size of primary α-Al decreases and the shape factor increases with the increase of the number of turns. When the cooling water flow rate is 450 L·h^(-1), the obtained semisolid slurry is optimal. During the preparation of the semisolid Al-Zn-Mg-Cu alloy slurry with low superheat pouring, the alloy melt has mixed inhibition and convection flow characteristics by "self-stirring". When the alloy melt flows through the serpentine channel, the chilling effect of the inner wall of the channel, the convection and mixed inhibition of the alloy melt greatly promote the heterogeneous nucleation and grain segregation. This effect destroys the dendrite growth mode under traditional solidification conditions, and the primary nuclei gradually evolve into spherical or nearspherical grains.

Optimization of the Water-Cooled Structure for the Divertor Plates in EAST Based on an Orthogonal Theory

An orthogoual experimental scheme was designed for optimizing a water-cooled structure of the divertor plate. There were three influencing factors： the radius R of the water- cooled pipe, and the pipe spacing L1 and L3. The influence rule of different factors on the cooling effect and thermal stress of the plate were studied, for which the influence rank was respectively R 〉 L1 〉 L3 and L3 〉 R 〉 L1. The highest temperature value decreased when R and L1 increased~ and the maximum thermal stress value dropped when R, L1 and L3 increased. The final optimized results can be summarized as： R equals 6 mm or 7 mm, L1 equals 19 mm, and L3 equals 20 mm. Compared with the initial design, the highest temperature value had a small decline~ and the maximum thermal stress value dropped by 19~ to 24~. So it was not ideal to improve the cooling effect by optimizing the geometry sizes of the water-cooled structure, even worse than increasing the flow speed, but it was very effective for dropping the maximum thermal stress value. The orthogoaal experimental method reduces the number of experiments by 80%, and thus it is feasible and effective to optimize the water-cooled structure of the divertor plate with the orthogonal theory.

Analysis of surface cracking in water-cooled rolls and heat transfer between furnace chamber and rolls in a direct flame furnace

In the direct fired furnace of a continuous annealing line, seal rolls are susceptible to deformation that leads to surface defects of steel strips. According to failure analysis, the reasons include improper structural design and heat imbalance. An improved design has been proposed to reduce stress concentration and thermal radiation. A heat transfer model has been employed to determine the proper water flow rate for roll cooling. Industrial application proves that seal rolls with the new design has less deformation and longer service life.

Fully Immersing Water-Cooled Radial Slab Laser and its Incoherent Beam Combination

A novel scheme of fully immersing water cooling is proposed for a Nd：glass radial slab laser. The slab medium is entirely immersed in the circulating water Ailing the pumping cavity, which enables much lower temperature and reasonably smaller thermal gradient in the slab medium. The radial slab is symmetrically and synchronously pumped by eight flash lamps, and produces multi-output beams with a total energy of 469md. Incoherent beam combination property of the multi-output beams is also investigated. The approach suggested here provides a way of scaling the slab lasers to much higher output levels and also a convenience for beam combinations.

The Corrected Simulation Method of Critical Heat Flux Prediction for Water-Cooled Divertor Based on Euler Homogeneous Model

An accurate critical heat flux（CHF） prediction method is the key factor for realizing the steady-state operation of a water-cooled divertor that works under one-sided high heating flux conditions.An improved CHF prediction method based on Euler＇s homogeneous model for flow boiling combined with realizable k-ε model for single-phase flow is adopted in this paper in which time relaxation coefficients are corrected by the Hertz-Knudsen formula in order to improve the calculation accuracy of vapor-liquid conversion efficiency under high heating flux conditions.Moreover,local large differences of liquid physical properties due to the extreme nonuniform heating flux on cooling wall along the circumference direction are revised by formula IAPWSIF97.Therefore,this method can improve the calculation accuracy of heat and mass transfer between liquid phase and vapor phase in a CHF prediction simulation of water-cooled divertors under the one-sided high heating condition.An experimental example is simulated based on the improved and the uncorrected methods.The simulation results,such as temperature,void fraction and heat transfer coefficient,are analyzed to achieve the CHF prediction.The results show that the maximum error of CHF based on the improved method is 23.7%,while that of CHF based on uncorrected method is up to 188%,as compared with the experiment results of Ref.[12].Finally,this method is verified by comparison with the experimental data obtained by International Thermonuclear Experimental Reactor（ITER）,with a maximum error of 6% only.This method provides an efficient tool for the CHF prediction of water-cooled divertors.

Creation and Development of Turbo-generators with Water-Cooled Stator and Rotor Windings in Shanghai Electrical Machinery Mfg Works

1. An Overview of Manufacture and Operation A turbine generator utilizing a new technology of electrical machinery industry, i.e. the windings of its stator and rotor all being inner water-cooled, was first successfully created in China and was known afterwards as a turbine generator with watercooled stator and rotor windings (Abbrev, TGWSR). The teachers from Zhejiang University came to Shanghai between

炉外热风冲天炉的热风单元与除尘风量设计

介绍了炉外热风冲天炉除尘系统处理风量的计算方法,分析了炉外热风冲天炉的除尘系统处理风量对热风单元工作的影响,并通过列举的国内外有关冲天炉的除尘风量参考数据,得出以下结论:(1)炉外热风冲天炉除尘系统的处理风量与热风单元的工作存在着密切的关系,且该类炉首先需要准确计算冲天炉除尘系统的处理风量;(2)需要选用风量和风压合适的风机,且风机风量不能过大;(3)除尘系统的风量调节必须以风机进口阀调节为主,不能用变频器对除尘风量进行大幅度调节。

冲天炉和电熔炉熔制岩棉之比较

冲天炉和电熔炉是制备岩棉熔体的两种生产方式与装备。通过阐述冲天炉和电熔炉两种熔制工艺,围绕原料及要求、能源及熔制方式、烟尘排放处理,对比两种工艺差别及效果,电熔炉在节省能源、减少排放、提高生产效率、利用固体废弃物和液态废渣等方面,具有明显的优势。

冲天炉尾气的消烟除尘和脱硫脱硝工艺

介绍了冲天炉尾气消烟除尘、脱硫、脱硝等技术问题,结合美国冲天炉的袋式除尘系统,重点说明了袋式除尘器的前级除尘器、袋式除尘器消烟除尘系统的设计要点和袋式除尘器的运行维护问题,同时阐述了冲天炉尾气脱硫和脱硝系统的工作原理。最后指出:冲天炉是一种经过人们长期使用并具有节能特点的铸铁熔化设备,按我国工业炉窑尾气污染物处理技术,其污染物排放量可以达到限定值以内,不会出现问题。

EC&S长炉龄热风水冷冲天炉简介及其应用

2007年潍柴引进了美国EC&S公司35t/h长炉龄热风水冷富氧冲天炉,配置2台80t保温电炉实现双联熔炼用于大批量生产发动机灰铸铁气缸体和气缸盖铸件。本文介绍了该35t/h长炉龄热风水冷富氧冲天炉主要系统及其应用情况。近几年的应用实践证明,在两班制生产条件下,35t/h冲天炉熔炼的铁水化学成分稳定,完全满足HT250、HT300和HT350材质柴油机气缸体、气缸盖的生产要求,适合于大批量连续生产,且具有自动化程度高、高效和环保的特点。

大型冲天炉-电炉双联熔炼生产高强度灰铸铁过程控制

介绍了铸造二期冲天炉-电炉双联熔炼工艺,要获得优质铁液,首先需控制原辅材料质量,质量稳定可控的炉料是获得优质铁液的先决条件;其次是熔炼工艺,标准化、严格的过程控制才能保证持续提供合格铁液。得益于从炉料到熔炼过程完善且不断优化的全流程管控,自投产以来累计熔化优质铁液100万t。通过严格的原铁液质量控制,配合适当的孕育与合金化处理,可生产高强度灰铸铁。

Flow Field and Temperature Field of Water-Cooling-Type Magnetic Coupling

At present, the water-cooling simulation of the water-cooled magnetic coupler is based on the water-cooled motor and the hydraulic coupler, which cannot accurately characterize the temperature distribution of the rotating watercooled coupling of the coupler. Focusing on rotating water cooling radiating, the present paper proposes simulating the water cooling temperature field as well as the flow field through the method of combining fluid-solid coupled heat transfer and MRF(Multiphase Reference Frame). In addition, taking an 800 kW magnetic coupling as an example, the paper optimizes the shape, number, cooling water inlet speed? and so on? of the cooling channel. Considering factors such as the complete machine’s temperature, and drag torque, it is proved that the cooling e ect is best when there are 36 involute curved channels and when the inlet speed is 3 m/s. Further, through experiments, the actual temperature values at six di erent positions when 50 kW and 70 kW thermal losses di er are measured. The measured values agree with the simulation results, proving the correctness of the proposed method. Further, data have been collected during the entire experimental procedure? and the variation in the coupling’s temperature is analyzed in depth, with the objective of laying a foundation for the estimation of the inner temperature rise as well as for the optimization of the structural design.

DEVELOPMENT OF SINGLE-PHASED WATER-COOLING RADIATOR FOR COMPUTER CHIP

In order to cool computer chip efficiently with the least noise, a single phase water-cooling radiator for computer chip driven by piezoelectric pump with two parallel-connection chambers is developed. The structure and work principle of this radiator is described. Material, processing method and design principles of whole radiator are also explained. Finite element analysis （FEA） software, ANSYS, is used to simulate the heat distribution in the radiator. Testing equipments for water-cooling radiator are also listed. By experimental tests, influences of flowrate inside the cooling system and fan on chip cooling are explicated. This water-cooling radiator is proved more efficient than current air-cooling radiator with comparison experiments. During cooling the heater which simulates the working of computer chip with different power, the water-cooling radiator needs shorter time to reach lower steady temperatures than current air-cooling radiator.

Mathematical model on heat transfer of water-cooling steel-stick bottom electrode of DC electric arc furnace

For predicting and controlling the melted depth of bottomelectrode during the process of steelmaking, the water-cooling steel-stick electrode is taken as an example, to analyze the process ofheat transfer, then 3D mathematical model by control capacity methodis built. At the same time, the measurement on the melted depth ofbottom electrode is conducted which verified the correctness of thebuilt mathematical model. On the base of verification, all kinds ofkey parameters are calculated through the application and a series ofresults are simulated. Finally, the optimum parameters are found andthe service life of bottom electrode is prolonged.

Research on the Flow and Heat Transfer Characteristics of a Water-Cooling Plate in a Heat Dissipation System

The water-cooling heat dissipation technology can solve the heat dissipation and noise problems of the calculation plate.Therefore,the structural design of the water-cooling plate directly affects its flow and heat transfer characteristics,which restricts the promotion and application of the technology.To this end,the water-cooling plate of a heat dissipation system was taken as the research object,and its flow and heat transfer characteristics were numerical simulated and experimental studied.Through comparative analysis,the rationality of the numerical simulation method was verified.Based on this,three improved schemes of water-cooling plate structure were proposed and numerical simulation was carried out,and the optimal model was verified by experiments.The results of the study show that compared with the original water-cooling plate,the optimized water-cooling plate has increased internal flow velocity and distributes uniformly,increased heat transfer amount by 4.2%,and the average temperature of the calculation plate decreased by 5.3%.

Giorgio Vasari’s Saint Michael the Archangel in the Cupola of Santa Maria del Fiore: A Neoplatonic Sphere

This essay discusses the manifold depictions of Saint Michael The Archangel in Italian Renaissance art,in particular in Giorgio Vasari’s imagery.It starts with a brief explanation of who Michael The Archangel is,explores his visual iconography in pagan,Judeo-Christian,and Byzantine imagery,and examines the impact of Renaissance Neoplatonism on the interpretation of Saint Michael and his symbolic roles.The Renaissance Neoplatonic philosopher Marsilio Ficino explained the significance of the Platonic celestial ladder as a spiritual vehicle for the human soul to achieve divine love.One step of this ladder is the Angelic Mind.It is here that the sparkling light of the realm of the Angelic Mind reveals the splendor and beauty of God’s grace.This is the realm where Michael,a Seraphim and a messenger of God,resides,delivering God’s messages of grace and love to humanity throughout the world.Giorgio Vasari(1511-1574)visualized these divine messages metaphorically in frescos on two major vaults.The first is in the small cupola of the Pope Pius V Chapel in the Vatican,once called Saint Michael’s Chapel,where between 1560 and 1566 Vasari and his assistants painted al fresco the Saint Michael and the Devils,a depiction of Michael the Archangel combatting vices personified as demons who want to prevent human beings from obtaining the divine grace that will allow their souls to ascend toward heaven(Figure 1).Between 1570 and 1574,Vasari continued his metaphorical visualization of God’s divine message in a large vault,the octagonal cupola of Santa Maria del Fiore,the Dome of the Cathedral of Florence,the major focus in this essay(Figure 2).He and his assistants painted al fresco the Last Judgment,portraying Saint Michael The Archangel residing in a heavenly realm-the divine reign of God,where he mediates and witnesses God’s divine judgment on humankind(Figure 13).Here,celestial trumpeters loudly announce the separation of good and bad souls of the terrestrial realm,Earth.The bad souls rapidly descend into a Dantesque infernal realm where demons capture them and transform them into hybrid forms.In contrast,the good souls quickly emerge from Earth to ascend into Heaven.Their skeletal figures transform into angelic beings,ready to receive divine grace and eternal love.

DYNAMIC MATHEMATICAL MODEL OF CHEMICAL COMPOSITION FOR MELTED IRON IN CUPOLA AND MICROCOMPUTER SIMULATION

Sequential melting theory is applied to reteal that fluctuation of chemical composition ofmelted iron in cupola is caused by the process of sequential melting. Fluctuation is incvitable andcyclc. Usting microcornputer dynamic simulation has confirmed that the fluctuation situation ofchemical composition cf melted iron is contistent with actuaa production on the whole.