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In the framework of joint effort between the Nuclear Energy Agency (NEA) of OECD, the United States Department of Energy (US DOE), and the Commissariat a l'Energie Atomique (CEA), France a coupled three-dimensional (3D) thermal-hydraulics/neutron kinetics benchmark for VVER-1000 was defined. The benchmark consists of calculation of a pump start-up experiment labelled V1000CT-1 (Phase 1), as well as a vessel mixing experiment and main steam line break (MSLB) transient labelled V1000CT-2 (Phase 2), respectively. The reference nuclear plant is Kozloduy-6 in Bulgaria. The overall objective is to assess computer codes used in the analysis of VVER-1000 reactivity transients. A specific objective is to assess the vessel mixing models used in system codes. Plant data are available for code validation consisting of one experiment of pump start-up (V1000CT-1) and one experiment of steam generator isolation (V1000CT-2). The validated codes can be used to calculate asymmetric MSLB transients involving similar mixing patterns. This paper summarizes a comparison of CATHARE and TRAC-PF1 system code results for V1000CT-1, Exercise 1, which is a full plant point kinetics simulation of a reactor coolant system (RCS) pump start-up experiment. The reference plant data include integral and sector average parameters. The comparison is made from the point of view of vessel mixing and full system simulation. CATHARE used a six-sector multiple 1D vessel thermal-hydraulic model with cross flows and TRAC used a six-sector, 18-channel coarse-mesh 3D vessel model. Good agreement in terms of integral parameters and inter-loop mixing is observed. 相似文献
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氧气生产单位保用户用气一旦出现较为紧张的局面时,如何正确处理保安全生产运行、保用户生产、安排抢修时间三者之间的关系,值得关注与研究。 相似文献
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简述了上海汽轮机有限公司(STC)与西门子公司首次合作制造的目前国内最大容量的外高桥900MW超临界机组的一些基本情况,介绍了在合作制造中为保证生产进度和质量而采取的工艺改进、技术攻关等措施,以及通过合作制造提升了我公司的制造能力和管理水平。 相似文献
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Fourteen commercial polyadipates and a polysebacate were analysed for their components of a molecular mass below 1000 Da, primarily with the aim of generating the background data for measuring the migration of this type of polymeric additives from plasticized PVC (e.g. cling films and gaskets of lids) into foods or food simulants. Since the composition of the material <1000 Da varies between the polyadipates, the main components must be identified to enable a correct quantification. Polyadipates differ in the diol used as linker, their termination (acid or alcohol) and in the end‐capping (free alcohols, acetylation, acylation with fatty acids, esterification with octanol/decanol). Gas chromatography (GC) provides good separation, but the material remaining in the column up to high temperatures decomposes and forms a hump in the rear part of the chromatogram. Examples of mass spectra are shown, the most indicative fragments pointed out and spectra of 159 components listed. The polyadipates and the sebacate are characterized by their structure, the main components <1000 Da and the fraction of material <1000 Da. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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M. A. Pikin Yu. V. Nesterov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):159-165
A mathematical model for analysis of process parameters of equipment in the second circuit of nuclear power plants is presented,
and the structure of the program and principles used for analysis of the equipment are described. A mathematical model for
analysis of the deaerator and steam generator is described in detail. A computational analysis of several transitional modes,
which is made possible on the basis of the mathematical model in question, is also presented in this paper, and a comparison
is made with test data.
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Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 16–22. 相似文献
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S. Langenbuch J. Hadek K.-D. Schmidt K. Velkov 《Progress in Nuclear Energy》2006,48(8):912-1Benchmark
The VVER-1000 Coolant Transient Benchmark consists of two phases and refers to experimental data from the Kozloduy Unit 6 Nuclear Power Plant in Bulgaria. The paper describes the modelling features and their impact on the results of the Exercise 1, Phase 1 of the Benchmark obtained by two ATHLET user groups, namely GRS and NRI. The simulated transient is a main coolant pump (MCP) switching on in one loop at reduced power while three other MCPs are in operation. Particular attention is paid to the influence of the reactor vessel modelling and especially of the nodalization in the upper plenum. The comparison and discussion of the two simulation results confirm that the two solutions with the ATHLET system code achieve quite good system response of the plant transient. 相似文献