涟钢中和场预配料系统的自动化改造

叙述了一种采用电子皮带称 +称量控制仪表 +PLC+变频调速器 +工控计算机及数据通信网络等组成的预配料自动控制系统。介绍了该系统的构成、过程监视、实时监控设计及其实现。改造后运行结果表明 ,单机配料精度由原来的± 3 %提高到± 1 % ,系统配料控制误差由原来的 5%减少到 2 %以内 ,为涟钢的烧结矿产量和质量提高发挥了较大作用 ,年增经济效益 1 2 0万元     

YNRQ型液体粘性软起动装置常见故障及处理

介绍了YNRQ型液体粘性软起动装置在使用过程中出现的一些常见故障,分析了故障原因及排除方法.     

NECP-X中基于改进泄漏项分割技术的二维/一维耦合输运方法

二维/一维耦合输运方法较好地平衡了效率与精度,因此被广泛应用于一步法全堆芯输运计算。二维/一维耦合输运方法中,由于泄漏项在方程右端,导致二维特征线法(MOC)计算时方程右端总源项在迭代过程中可能成为负值,造成迭代发散。本文针对二维/一维耦合输运计算中的负源项问题,提出了一种改进的泄漏项分割方法。新的泄漏项分割方法可在不造成计算精度损失和仅增加有限内存的条件下,显著提高二维/一维耦合输运方法的稳定性。通过强泄漏算例、C5G7基准题、VERA-3A基准题等进行测试,表明该方法对提高二维/一维耦合输运方法稳定性具有显著的效果。     

Conceptual core design study of an innovative small transportable lead‐bismuth cooled fast reactor (SPARK) for remote power supply

An innovative small transportable lead‐bismuth cooled fast reactor, named SPARK, with rated power of 20 MWth is proposed to operate for 20 years without refueling as a remote power supply. The SPARK core neutronics and thermal‐hydraulics design and preliminary safety analysis were performed in the current study. In order to achieve a compact and light‐weight core design with enhanced transportability and passive safety, the selection of reflector materials, the optimization of fuel assembly design and radial core zoning loading, and the reactivity control system design were accomplished. MgO was selected as the optimal reflector material due to its good neutron reflecting characteristics and low density. The fuel assembly design was optimized to obtain a long lifetime of core and low peak cladding surface temperature. To flatten radial power distribution, 3 radial zones were designed with different fuel pin diameters. A liquid absorber control system was implemented using ⁶Li‐enriched liquid lithium as the neutron absorber, which significantly reduces the core height. To reduce the initial excess reactivity, fixed absorbers were installed in the scram assemblies for the first half life and then replaced by fixed reflectors for the second half life. Based on the parametric study, the optimized core design was determined, and the core neutronics and thermal‐hydraulics performances were evaluated. The objective core lifetime of 18 effective full power years was fulfilled with the compact and light‐weight core design, and the thermal design constraints were satisfied during the whole life. Both the control and scram systems proved to independently provide sufficient shutdown margins. Using the quasi‐static reactivity balance method, the passive safety characteristics of the optimized core design were analyzed based on 5 anticipated transients without scram. Passive shutdown was achieved due to the negative reactivity feedback. The critical design constraint of the peak cladding surface temperature was satisfied for all transients.     

国内外主要射孔技术发展评述

文章在调研国内外相关资料的基础上,对国内外射孔技术的现状进行了分析。对目前我国各油气田所采用的主要射孔技术作了一个较为详细的介绍,涉及到各种射孔技术的原理、特点、适用范围,也提到了国外一些比较先进的射孔技术。文中对各种射孔技术作了一个概括性的总结,指出应该推广最有潜力的射孔技术,提出我国应在射孔机理研究、射孔工艺技术等方面多做研究工作,加强国际合作,提高我国的射孔技术水平。     

水文行业的传统文化及其战略思考

一、水文行业传统文化的精神特质 水文行业传统文化是伴随着社会文明的传播、交流和融合而逐步形成的．它以国民经济为基础,以水利建设为支柱。以水文化为核心,具有追求严谨．强调实行,重传统、反功利的特点。与其他自然学科一样,水文行业在精心培育专业体系的同时,也孕育了顽强的精神动力、思想观念和行为模式。这种根深蒂固的影响,在推动水文事业发展的同时．也设置了障碍;     

南水北调西四环暗涵工程回填灌浆施工

回填灌浆作为南水北调北京段西四环暗涵工程浅埋暗挖法施工的一道主要工序,也是有效控制地面沉降的一种重要手段,其施工质量的优劣直接影响建筑物的稳定与安全。南水北调西四环暗涵工程的浅埋暗挖法施工中的回填灌浆,采取孔外循环、孔内填压的方式,并在孔口设止浆塞和回浆装置,以保证围岩的灌浆压力;此外,对灌浆中断、串浆、漏浆、吸浆量较大孔等特殊情况采取了一系列处理措施,以保证施工质量。     

Transmission probability method based on triangle meshes for solving the unstructured geometry neutron transport problem

The fuel assembly or core with unstructured geometry is frequently used in the advanced reactor. To calculate the fuel assembly, the transmission probability method (TPM) is widely used. However, the rectangular or hexagonal meshes are mainly used in the TPM codes for the normal core structure. The triangle meshes are most useful for expressing the complicated unstructured geometry. Even though the finite element method and Monte-Carlo method are well suited for solving the unstructured geometry problem, they are very time-consuming. Therefore, a TPM code based on the triangle meshes is developed here. This code was applied to the hybrid fuel geometry, and compared with the results of the MCNP code and other codes. The results of the comparison were consistent with each other. The TPM with triangle meshes can thus be applied to the two-dimensional arbitrary fuel assembly.     

Wavelet-based angular dependence analysis of the heterogeneous calculation on MOX fuel lattice

A wavelet-based transport method is developed to satisfy the high order angular approximation, which has been proved to be necessary in the heterogeneous calculation of MOX fuel lattice. Based on the new angular discretization scheme, the angular dependence of flux is analysed to find out the origin of complicated angular anisotropy and its effects on the heterogeneous calculation. Both of the geometric and neutronic effects are investigated quantitatively to find out the angular dependence in heterogeneous calculations. Comparisons between the traditional S_N angular discretization scheme and wavelet-based scheme are analysed to indicate the challenges brought from the MOX fuel lattice heterogeneous calculation. An effective solution is given by using wavelets in the angular discretization of neutron transport equation. Improvements of high order angular approximation are suggested.     

用于乏燃料组件上下端部活化源项分析的截面库研究北大核心CSCD

基于乏燃料组件上下端部活化源项精细化分析的需求,自制精细化问题相关截面库,并通过对比分析,研究不同截面库应用特点:活性区截面库和热中子截面库应用于活化源项计算时均存在较大的计算误差;组合截面库对共振群和快群截面的处理偏保守,当程序应用于上下端头活化源项计算时,分析结果偏保守;基于问题相关中子能谱自制的反应截面更加接近真实情况,基于此的计算结果也最接近真实情况。