The analysis of thermal cycle of steam power stations on ultrasupercritical parameters.

W artykule przedstawiono wyniki analizy termodynamicznej trzech obiegów cieplnych elektrowni parowych na parametry ultranadkrytyczne: 35 MPa i 700oC. Analizę przeprowadzono dla obiegów o różnych sposobach napędu pompy wody zasilającej. Obliczenia optymalizacyjne wykonano z wykorzystaniem algorytmu genetycznego.In the paper the results of the thermodynamic analysis of three thermal cycle of steam power stations on ultrasupercritical parameters: 35 MPa and 700oC were presented. The analysis for cycles about different manners of the drive pump feedwater was made. Optimization calculations with use of a genetic algorithm were performed

Environmental interaction assessment of VOC’s emission from printing plant hot rotary heat-set

The paper presents an analysis of gaseous emissions arising from the operations of printing using a printing process hot offset rotary. The first part presents the general characteristics of the process and the paint used. The following part shows the results of modelling the emission of pollutants according to the efficiency of the cleaning system, as well as depending on other parameters influencing the dispersion process impurities

Evolution of microstructure and residual stress during annealing of austenitic and ferritic steels

International audienceIn this work the recovery and recrystallization processes occurring in ferritic and austenitic steels were studied. To determine the evolution of residual stresses during material annealing the nonlinear sin 2 ψ diffraction method was used and an important relaxation of the macrostresses as well as the microstresses was found in the cold rolled samples subjected to heat treatment. Such relaxation occurs at the beginning of recovery, when any changes of microstructure cannot be detected using other experimental techniques. Stress evolution in the annealed steel samples was correlated with the progress of recovery process, which significantly depends on the value of stacking fault energy

Stress evolution in plastically deformed austenitic and ferritic steels determined using angle- and energy-dispersive diffraction

In the presented research, the intergranular elastic interaction and the second-order plastic incompatibility stress in textured ferritic and austenitic steels were investigated by means of diffraction. The lattice strains were measured inside the samples by the multiple reflection method using high energy X-rays diffraction during uniaxial in situ tensile tests. Comparing experiment with various models of intergranular interaction, it was found that the Eshelby-Kr¨oner model correctly approximates the X-ray stress factors (XSFs) for different reflections hkl and scattering vector orientations. The verified XSFs were used to investigate the evolution of the first and second-order stresses in both austenitic and ferritic steels. It was shown that considering only the elastic anisotropy, the non-linearity of sin2ψ plots cannot be explained by crystallographic texture. Therefore, a more advanced method based on elastic-plastic self-consistent modeling (EPSC) is required for the analysis. Using such methodology the non-linearities of cos2φ plots were explained, and the evolutions of the first and second-order stresses were determined. It was found that plastic deformation of about 1–2% can completely exchange the state of second-order plastic incompatibility stresses

Multireflection grazing-incidence X-ray diffraction: A new approach to experimental data analysis

The multireflection grazing-incidence X-ray diffraction method is used to test surface stresses at depths of several micrometres in the case of metal samples. This work presents new ways of analysing experimental data obtained by this method for Ni samples exhibiting significant elastic anisotropy of crystals. Three different methods of determining biaxial stresses and lattice parameter were compared. In the first approach, the calculations were performed using the linear least-squares method, and then two simplified procedures based on simple linear regression (weighted and non-weighted) were applied. It was found that all the tested methods give similar results, i.e. almost equal values of the determined stresses and lattice parameters and the uncertainties of their determination. The advantage of analyses based on simple linear regression is their simplicity and straightforward interpretation, enabling easy verification of the influence of the crystallographic texture and the presence of shear stresses, as well as graphical determination of the stress-free lattice parameter

A multireflection and multiwavelength residual stress determination method using energy dispersive diffraction

The main focus of the presented work was the investigation of structure and residual stress gradients in the near-surface region of materials studied by X-ray diffraction. The multireflection method was used to measure depth-dependent stress variation in near-surface layers of a Ti sample (grade 2) subjected to different mechanical treatments. First, the multireflection grazing incidence diffraction method was applied on a classical diffractometer with Cu Kα radiation. The applicability of the method was then extended by using a white synchrotron beam during an energy dispersive (ED) diffraction experiment. An advantage of this method was the possibility of using not only more than one reflection but also different wavelengths of radiation. This approach was successfully applied to analysis of data obtained in the ED experiment. There was good agreement between the measurements performed using synchrotron radiation and those with Cu Kα radiation on the classical diffractometer. A great advantage of high-energy synchrotron radiation was the possibility to measure stresses as well as the a0 parameter and c0/α0 ratio for much larger depths in comparison with laboratory X-rays. © 2018 International Union of Crystallography

Residual stress field in steel samples during plastic deformation and recovery processes

International audienceX-ray diffraction method was applied to measure residual stresses and stored elastic energy in deformed and annealed polycrystalline ferritic and austenitic steel samples. Orientation distribution of incompatibility stresses created during elastoplastic deformation was determined and presented in Euler space. Using deformation models, the second order stresses were correlated with different types of intergranular interactions occurring in the studied materials. An important decrease of the first and the second order residual stresses was observed during recovery and recrystallization processes. Diffraction peaks related to dislocations density were studied and correlated with stress variation during annealing process. Differences in stress relaxation between ferritic and austenitic samples were explained by different values of the stacking fault energy, which influences climb of dislocations

Intramuscular triacylglycerol in energy metabolism during exercise in humans

Multireflection grazing-incidence X-ray diffraction (MGIXD) was used to determine the stress- and strain-free lattice parameter in the surface layer of mechanically treated (polished and ground) tungsten and austenitic steel. It was shown that reliable diffraction stress analysis is possible only when an appropriate grain interaction model is applied to an anisotropic sample. Therefore, verification of the X-ray stress factors (XSFs) was accomplished by measuring relative lattice strains during an in situ tensile test. The results obtained using the MGIXD and standard methods ( and geometries) show that the Reuss and free-surface grain interaction models agree with the experimental data. Moreover, a new interpretation of the MGIXD results was proposed and applied for the first time to measure the probability of stacking faults as a function of penetration depth for a polished and ground austenitic sample. The XSF models verified in the tensile test were used in the analysis of residual stress components

Multireflection grazing-incidence X-ray diffraction: A new approach to experimental data analysis

International audienceThe multireflection grazing-incidence X-ray diffraction method is used to test surface stresses at depths of several micrometres in the case of metal samples. This work presents new ways of analysing experimental data obtained by this method for Ni samples exhibiting significant elastic anisotropy of crystals. Three different methods of determining biaxial stresses and lattice parameter were compared. In the first approach, the calculations were performed using the linear least-squares method, and then two simplified procedures based on simple linear regression (weighted and non-weighted) were applied. It was found that all the tested methods give similar results, i.e. almost equal values of the determined stresses and lattice parameters and the uncertainties of their determination. The advantage of analyses based on simple linear regression is their simplicity and straightforward interpretation, enabling easy verification of the influence of the crystallographic texture and the presence of shear stresses, as well as graphical determination of the stress-free lattice parameter

The GOSPOSTRATEG-HTR project results

Ochrona klimatu wymaga wdrożenia bezemisyjnych źródeł energii, takich jak reaktory jądrowe. Reaktory wysokotemperaturowe mogą stanowić doskonałe uzupełnienie wielkoskalowej energetyki jądrowej, poprzez zaopatrzenie rynku energetycznego w wysokotemperaturowe ciepło, do różnych procesów technologicznych. Pierwszym krokiem na drodze do wdrożenia technologii reaktorów wysokotemperaturowych w Polsce była realizacja projektu GOSPOSTRATEG-HTR. Niniejszy artykuł stanowi podsumowanie najważniejszych celów i osiągnięć projektu.Climate protection requires the deployment of zero-emission energy sources, such as nuclear reactors. Hightemperature reactors can be a perfect complement to large-scale nuclear energy by supplying the energy market with hightemperature heat for various technological processes. The first step towards the implementation of high-temperature reactor technology in Poland was the implementation of the GOSPOSTRATEG-HTR project. This article is a summary of the most important goals and achievements of the project