Prediction of Losses in Flow Through the Last Stage of LP Steam Turbine

The aim of presented work was the prediction of the losses in the wet steam flow through the last stage of 200MW steam turbine LP part.To this end,three numerical tools were used.The first method was the streamline curvature method (SCM) used on the meridional plane with losses correlations.The next two methods,TASCflow commercial CFD code and an in-house CFD code,based on the solution of the Reynolds- averaged Navier-Stokes equations (RANS).Ap- plication of three independent numerical tools al- lowed to make the more reliable losses analysis and made possible to compare applied numerical methods with each other. For the flow modeling in the last stage of LP steam turbine the various two-phase flow models were used and compared.The equilibrium model and non-equi- librium models with homogeneous and/or heterogeneous condensation were considered.The boundary conditions at the inlet and outlet from the stage were selected in such way to get the beginning of the homogeneous condensation process in the sta- tot.It corresponded to the part load of the turbine, i.e.140MW power and pressure in condenser 2.7kPa.     

BHP公司掌握联接酸洗冷轧机技术

ＢＨＰ公司掌握联接酸洗冷轧机技术据ＳｔｅｅｌＴｉｍｅｓｌｎｔｅｒｎａｔｉｏｎ１９９１年３月报道，联接酸洗冷轧机（ＣＰＣＭ）在ＢＨＰ钢镀层产品分公司Ｓｐｒｉｎｇｈｉｌｌ厂投产运行已两年。此生产线采用世界上第一流湍流酸洗设备（系统）。串列式冷轧机与酸洗线...     

Anion buffering in the internal electrolyte resulting in extended durability of phosphate-selective electrodes

The decomposition of the ionophore uranyl salophene in a polymeric membrane is the main source of the deterioration of phosphate-selective electrodes in time. Due to the efficient buffering of both phosphate and uranyl ions in the internal electrolyte solution, a significant decrease of the rate of decomposition of uranyl salophene in the membrane was observed, improving the lifetime of phosphate-selective electrodes. The most efficient buffering of such ions, resulting in the best sensor durability, was obtained using the internal electrolyte solution containing barium-uranyl phosphate mineral, meta-uranocircite II.     

速射加热系统比感应加热带来高速度高质量

据June Iron and Steel Engineer1994年P55报道:气化产品及化学产品公司已经引进了一种先进的快速加热技术。这种加热技术能使金属厂家认识到.以天然气为主的燃烧系统与感应加热相比,在成本大致相同的情况下能带来高速度和高质量。利用氧气/天然气火焰直接接触的速射加热系统的专利,对直径为111～222mm的产品达到76～101℃/min的加热速率。它可与电感应加热相比,并比传统的空气/燃料加热炉快得多。由于这种快速加热技术与其它加热系统相比能提高生产率,减少氧化铁皮     

Evolution of phase stresses in Al/SiC_p composite during thermal cycling and compression test studied using diffraction and self-consistent models

In this work,the evolutions of stresses in both phases of the Al/SiCp composite subjected to thermal cycling during in situ compression test were measured using Time of Flight neutron diffraction.It was confirmed that inter-phase stresses in the studied composite can be caused by differences in the coefficient of thermal expansion for the reinforcement and matrix,leading to a different variation of phase volumes during sample heating or cooling.The results of the diffraction experiment during thermal cycling were well predicted by the Thermo-Mechanical Self-Consistent model.The experimental study of elastic-plastic deformation was carried out in situ on a unique diffractometer EPSILON-MDS(JINR in Dubna,Russia)with nine detector banks measuring interplanar spacings simultaneously in 9 orientations of scattering vector.For the first time,the performed analysis of experimental data allowed to study the evolution of full stress tensor in both phases of the composite and to consider the decomposition of this tensor into deviatoric and hydrostatic components.It was found that the novel Developed Thermo-Mechanical SelfConsistent model correctly predicted stress evolution during compressive loading,taking into account the relaxation of thermal origin hydrostatic stresses.The comparison of this model with experimental data at the macroscopic level and the level of phases showed that strengthening of the Al/SiCp composite is caused by stress transfer from the plastically deformed A12124 matrix to the elastic SiCp reinforcement,while thermal stresses relaxation does not significantly affect the overall composite properties.     

LTV钢铁公司克利夫兰厂新的直接热装联合机组

ＬＴＶ钢铁公司克利夫兰厂新的直接热装联合机组［美］ＮｏｒｍａｎＬ．Ｓａｍｗａｙｓ１前言在过去的７年中，美国林－坦科－沃特钢铁公司（ＬＴＶ）改造设备总花费为２３亿美元，从而不仅使质量达到具有世界竞争力的水平，而且还大幅度地降低设备运行费用。克利夫兰厂重...     

Adsorption dynamics of chlorinated hydrocarbons from multi-component aqueous solution onto activated carbon

The results and a numerical simulation of studies on dynamics of the adsorption from seven-component aqueous solution of light chlorinated hydrocarbons on activated carbon have been presented. Aqueous solution of 1,2-dichloroethane (12DCE), 1,1,2,2-tetrachloroethane (S-TET), chloroform (CHCl(3)), carbon tetrachloride (CCl(4)), 1,1-dichloroethene (VDC), perchloroethene (PER) and 1,1,2-trichloroethene (TRI) was used. Concentrations of chlorohydrocarbons were similar as in wastewater from vinyl chloride plant. A cell model that incorporates the diffusion through a laminar layer of liquid around a particle was used to describe the experimental results. The applied calculation methods, which take kinetics into account, allows to well describe a phenomenon of dynamic adsorption. Mean relative deviations between the experimental and calculated values amounted 17%. The breakthrough curves become steeper along with an increase of the bed height. A consistency of the experimental results with those calculated indicates for a negligible contribution of the axial diffusion on the dynamic adsorption process of light chlorinated hydrocarbons from aqueous solution under the hydrodynamic conditions corresponding to the Reynolds number equal to 1.3. Determined optimal bed height for waste linear flow rate-15 cm/min is in the range 80-120 cm.     

加拿大钢铁公司开发的冷轧镀锡原板和轧制净化薄板用的单一轧制…

镀锡原板和净化薄板用的单一轧制油具有许多优点，包括合并贮油槽，改善带钢清洁度，减少退火循环时间并最终可提高生产率达１０％。     

Transport of traffic-related aerosols in urban areas

This study was undertaken to assess the influence of traffic on particulate air pollution in an urban area, and to characterise the short-range transport of the aerosols generated by traffic. The study was conducted in Kraków, a city located in southern Poland with a population of approximately 800,000. Aerosol samples were collected using automatic sampling equipment at five sites located at different distances from the main road in Kraków, ranging from 5 to 1500 m. The sampling set-up allowed standardisation of the results due to continuous determination of the meteorological parameters (temperature, atmospheric pressure, wind speed and direction, rainfall and humidity). Aerosol particles were separated according to aerodynamic diameter into two size fractions: > 1.9 microm (coarse fraction); and 1.9-72 microm (fine fraction). The concentrations of 27 elements were measured in both size fractions (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Zr, Ba, Pb). The multielement analyses were performed by Particle-Induced X-ray Emission (PIXE) spectrometry. Traffic contribution to particulate air pollution was determined on the basis of 13 elements which were present above the detection limit in all samples (Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Cu, Zn, Pb). It was found that the traffic contribution in the coarse size fraction was approximately 80% up to 150 m from the road; it dropped abruptly by a factor of 2 over a distance of 150-200 m and declined further to 20% at 1500 m from the road. Traffic contribution for the fine particle concentrations of individual elements was 50-70% in the close vicinity of the road (5 m); then there was a decrease, followed by an increase at a greater distance from the road. Possible explanations for this behaviour of the fine particles are given.     

In situ neutron diffraction unravels deformation mechanisms of a strong and ductile Fe Cr Ni medium entropy alloy

We investigated the mechanical and microstructural responses of a high-strength equal-molar medium entropy Fe Cr Ni alloy at 293 and 15 K by in situ neutron diffraction testing. At 293 K, the alloy had a very high yield strength of 651 ± 12 MPa, with a total elongation of 48% ± 5%. At 15 K, the yield strength increased to 1092 ± 22 MPa, but the total elongation dropped to 18% ± 1%. Via analyzing the neutron diffraction data, we determined the lattice strain evolution, single-crystal elastic cons...