Animation model of Krško nuclear power plant for RELAP5 calculations

Today most software applications, also in the nuclear field, come with a graphical user interface. The first graphical user interface for the RELAP5 thermal-hydraulic computer code was called the Nuclear Plant Analyzer (NPA). Later, Symbolic Nuclear Analysis Package (SNAP) was developed. The purpose of the present study was to develop SNAP animation model of Krško nuclear power plant (NPP) for RELAP5 calculations with the aim to help analyze the results. In addition, the reference calculations for Krško full scope simulator validation were performed with the latest RELAP5/MOD3.3 Patch 03 code and compared to previous RELAP5 versions to provide verified source data, needed to demonstrate animation model. In total six scenarios were analyzed: two scenarios of the small-break loss-of-coolant accident, two scenarios of the loss of main feedwater, a scenario of the anticipated transient without scram, and a scenario of the steam generator tube rupture. The use of SNAP for animation of Krško nuclear power plant analyses showed several benefits, especially better understanding of the calculated physical phenomena and processes. It can be concluded that an animation tool was created, which enables to analyze very complex accident scenarios. The graphical surface helps keeping the overview and focusing on the main influences. Also, the use of such support tools to system codes may significantly contribute to better quality of safety analysis.     

Nuclear data evaluation of Mn by the EMPIRE code with emphasis on the capture cross-section

Manganese is one of the constituents of alloys for structural components of fission and fusion devices and a well-known neutron dosimeter; however, existing ENDF-B/VII.0 ⁵⁵Mn evaluation was produced by Shibata (1989). This work is an attempt to re-evaluate neutron-induced cross-sections of ⁵⁵Mn using the latest release of the EMPIRE code. Sensitivity studies on the physical and fitting parameters are presented, with special emphasis on the capture and neutron inelastic cross-sections. A calculated nuclear data file in ENDF-6 format of the neutron interaction cross-sections is produced. It extends up to 150 MeV, which is of interest for fusion and accelerator driven system applications. This evaluation is compared with the ENDF/B-VII.0 evaluation and with a selection of experimental microscopic cross-sections. The evaluation is tested using integral data: the OKTAVIAN integral experiment on a manganese shell and an FNG experiment with manganese activation foils. Benchmark results provide needed feedback for the refinement of the physics parameters.     

Mechatronische Modellierung und Simulation der Dynamik von Walzanlagen

Rolling mills represent mechatronic systems with high complexity. As the dynamic behavior of a mill is crucial for its performance, dynamic simulation models are indispensable today for evaluating concepts for revamp and new design. Through modularization of the simulation model the high complexity can be mastered and flexibility of the total simulation model is achieved.     

Artificial Dim Light at Night during Pregnancy Can Affect Hormonal and Metabolic Rhythms in Rat Offspring

Artificial light at night (ALAN) is considered an environmental risk factor that can interfere with the circadian control of the endocrine system and metabolism. We studied the impact of ALAN during pregnancy on the hormonal and biochemical parameters in rat pups at postnatal (P) days P3, P10, and P20. Control dams (CTRL) were kept in a standard light-dark regime, and ALAN dams were exposed to dim ALAN (<2 lx) during the whole pregnancy. A plasma melatonin rhythm was found in all CTRL groups, whereas in ALAN pups, melatonin was not rhythmic at P3, and its amplitude was lowered at P10; no differences were found between groups at P20. Plasma corticosterone was rhythmic at P20 in both groups, with decreased mesor in ALAN pups. Plasma thyroid hormones exhibited an inconsistent developmental pattern, and vasopressin levels were suppressed at the beginning of the dark phase at P20 in ALAN compared to CTRL. Glucose and cholesterol showed significant daily rhythms in CTRL but not in ALAN offspring at P3. Exposure to ALAN during pregnancy disturbed the development of daily rhythms in measured hormones and metabolites, suggesting that ALAN during pregnancy can act as an endocrine disruptor that can interfere with the normal development of the progeny.     

Low-order parametric force model for a salient-pole synchronous machine with eccentric rotor

In this paper, a low-order parametric force model to represent the electromagnetic force on an eccentric rotor of a salient-pole synchronous machine was developed and verified. The force model with parameters estimated from the results of impulse method showed excellent performance. The proposed model allowed quick and accurate calculation of the electromagnetic force at the desired whirling frequency values and provided an opportunity to effectively combine the electromagnetic and mechanical analyses of electrical machines. Besides, results presented in this paper also verified the suitability of computationally efficient impulse method for the analysis of a synchronous machine.     

Kinetik und Mechanismus der Oxydation und Reduktion von Wüstit in Wasserdampf-Wasserstoff-Gemischen

Deuterium-Austausch zwischen Wasserdampf und Wasserstoff an der Wüstitoberfläche. Widerstandsmessungen zur Untersuchung der Sauerstoffübertragung. Nachweis der Teilschritte H₂O = OH(ad) + H(ad) und OH(ad) = O(ad) + H(ad) bei der Sauerstoffübertragung. Geschwindigkeitsgleichungen der Teilschritte. Abhängigkeit von Druck, Sauerstoffaktivität und Temperatur. Kontrolle der Reaktionsgeschwindigkeit durch die Teilreaktionen.     

Probleme der Querkraftbiegung des geraden Stabs

Zusammenfassung Aus den Verformungsbedingungen für einen dünnwandigen Stabquerschnitt lassen sich beim zweidimensionalen Spannungszustand die Verw?lbung des Querschnitts durch die Querkraft und daraus dann die von der Querkraft hervorgerufenen Normalspannungen ermitteln. Man kann auch die Verschiebung der Stabachse durch die Querkraft auf diese Weise berechnen und die jetzt übliche, von A. Ritter stammende N?herungsformel durch einen genauen Ausdruck ersetzen. Das Verfahren wird an zwei Beispielen, dem Rechteckquerschnitt und dem Kreisringquerschnitt, n?her erl?utert.