船用核动力装置稳态运行方式探讨

根据船用核动力装置运行的特点，在分析研究冷却剂平均温度和蒸汽压力恒定的所谓“双恒定”运行方式的基础上，提出了在装置运行的低负荷区域保持冷却剂平均温度和蒸汽压力恒定的“准恒定”运行方式，分析了其稳态运行特性。     

船用核动力装置专家系统技术研究

以船用核动力装置为研究对象 ,建立了运行在仿真机上的全工况核动力装置运行仿真系统。利用智能专家控制理论 ,建立了能够管理整个装置运行的 ,能对典型运行故障进行检测与诊断的管理运行专家系统。此系统在出现故障时能及时调用知识库专家知识进行专家推理 ,分析核动力装置控制实际运行中典型故障产生的原因及解决方法、故障诊断处理具有实时性 ;利用神经网络理论 ,建立了神经网络故障检测与诊断专家系统 ,此系统将不断检测核动力装置各系统 ,并根据检测数据给出故障诊断结果。结果表明 ,在核动力装置三层智能控制结构下 ,利用神经网络故障检测与诊断专家系统对船舶核动力装置可能的运行故障进行险测与诊断 ,利用运行管理专家系统对核动力装置进行运行管理 ,提高了船用核动力装置的运行性能。所进行的专家系统研究对船用核动力装置的安全运行具有一定的指导意义     

微机型船用核动力工程仿真器系统初步设计

基于船用核动力装置安全管理、开发研究的需求及核电站仿真技术的发展，分析了研制微机型船用核动力工程仿真器系统的重要意义。按软件工程的思想，从仿真器系统的功能设计、总体设计、模块设计三方面论述了该系统的设计思路及实现方法，并对日本核动力舰船“陆奥”号的回路系统进行了初步的模拟设计。该系统的实现将进一步提高船用核动力装置的优化设计、安全运行和科学管理水平。     

船用核动力装置净化系统运行安全分析研究

基于船用核动力装置运行安全的需要,阐述运行安全分析研究的特点和重要性。开发了核动力装置全范围运行分析软件,并对一回路净化系统典型事故进行了运行分析,给出了事故判别和处置的措施。所用运行分析软件和方法可满足船用核动力装置动态特性分析、事故处理规程制定和验证等工作的需要。     

套管式直流蒸汽发生器负荷跟动态特性分析

新型核动力装置采用紧凑型的套管式直流蒸汽发生器,根据传热特点,对其热工特性进行了分析。采用主冷却剂平均温度不变和二回路侧蒸汽压力不变的双恒定运行方案及经典PID控制器和负荷跟随运行模式,结合SCDAP/RELAP5/MOD3.4程序,研究了套管式直流蒸汽发生器的动态特性,分析了降负荷时套管式直流蒸汽发生器的动态响应过程。结果表明,通过优化PID控制器参数,对给水流量进行精确控制,可满足蒸汽压力恒定的控制策略,实现双恒定运行方案,使一、二回路的运行达到较好的协调;套管式直流蒸汽发生器升降功率速度快,蒸汽压力稳定,且动态响应时间短。     

套管式直流蒸汽发生器负荷跟随动态特性分析

新型核动力装置采用紧凑型的套管式直流蒸汽发生器,根据传热特点,对其热工特性进行了分析。采用主冷却剂平均温度不变和二回路侧蒸汽压力不变的双恒定运行方案及经典PID控制器和负荷跟随运行模式,结合SCDAP/RELAP5/MOD3.4程序,研究了套管式直流蒸汽发生器的动态特性,分析了降负荷时套管式直流蒸汽发生器的动态响应过程。结果表明,通过优化PID控制器参数,对给水流量进行精确控制,可满足蒸汽压力恒定的控制策略,实现双恒定运行方案,使一、二回路的运行达到较好的协调;套管式直流蒸汽发生器升降功率速度快,蒸汽压力稳定,且动态响应时间短。     

基于ESD的船用核动力装置一回路系统失水事故的事件序列

针对船用核动力装置事故分析的特点,从核动力装置运行安全的角度出发,采用基于事件序列图(ESD)和运行安全分析的联合分析方法,建立船用堆一回路系统失水事故的ESD模型。分析研究事故的演变过程和后果,获得完整的事件序列。     

核动力船机动航行对一回路自然循环驱动力的影响

针对船用核动力装置技术性能要求和运行特点,分析了舰船常见的机动动作对于一回路自然循环驱动力的影响,分别就一体化堆型和分布式堆型给出了计算结果,得出了相应的结论.这些结论对于核动力装置一回路系统特别是有自然循环能力要求的核动力装置一回路系统的运行管理有重要意义.     

采用OTSG的一体化核动力装置运行协调性分析与仿真

以采用直流蒸汽发生器(OTSG)的小型核动力装置(MRX)为研究对象,基于堆芯和蒸汽发生器等主要部件的数学模型,按照MRX控制方案设计双恒定运行的控制方法,以实现装置在功率变化时的快速跟踪响应。Matlab/Simulink软件仿真结果显示MRX系统的控制方案是有效的,二回路系统的动作时间相对较长,给水流量变化的速度低于一回路负荷的变化,在实际应用中应考虑采用快速响应的电动泵。     

船用核动力二回路热力系统动态仿真

基于船用核动力装置运行安全分析,建立了二回路系统两相流通用仿真软件模型,实现了人工干预条件下复杂两相流流体网络系统的动态特性实时仿真,拓展了目前核动力装置通用安全分析程序的研究范围.以二回路快速降负荷为例,对仿真模型的性能进行了验证.结果表明:该软件模型能准确反映船用二回路系统的动态特性,可用于事故处置规程和控制系统功能的验证.该模型也可用于核电站饱和蒸汽系统仿真软件的开发.     

The feasibility of cooling heavy-water reactors with supercritical fluids

It appears technically feasible to use supercritical carbon dioxide as a coolant for a CANDU-type reactor. A new supercritical loop is proposed in which the reactor is cooled by a single-phase fluid pumped in a high density liquid-like state. The supercritical fluid-cooled reactor has the advantage of gas-cooled reactors of avoiding dryout, and of liquid-cooled reactors of low coolant-circulation power. By eliminating dryout, the maximum operating temperature of the fuel sheath can be increased to 1021°F (550°C) for existing Canadian fuel bundles, with a coolant exit temperature of 855°F (458°C) producing steam comparable to that of conventional fossil-fuel plants. Since the reactor coolant exit temperature from the steam generator may be as high as 280°F (138°C) low-pressure steam may also be produced. A new dual-reheat cycle is proposed with an ideal overall plant efficiency of 33%, comparable to the Pickering generating station.     

AC600非能动安全壳冷却系统冷凝传热系数评价

用ＡＣ６００非能动安全壳冷却系统三维热工水力分析程序ＰＣＣＳＡＣ－ＭＤ,对几种常用的冷凝传热系数结构关系式进行了比较。这些结构关系式包括Ｕｃｈｉｄａ关系式,Ｇｉｄｏ－Ｋｏｅｓｔｌ关系式,Ｔａｇａｍｉ关系式和基于传热传质相似原理的关系式。     

非能动余热排出系统数学模型研究与运行特性分析

利用某型核动力装置非能动余热排出系统1:10原理性试验的8个稳态工况、6个启动工况的试验数据,验证RELAP5/MOD3.2程序对本类型非能动余热排出系统的适用性。结果表明:垂直管内蒸汽凝结换热系数对两相流自然循环的流动与传热影响大;RELAP5/MOD3.2程序过低估算了垂直管内蒸汽流速对蒸汽凝结换热系数的影响,计算结果与试验结果偏差大。对RELAP5/MOD3.2程序垂直管内的蒸汽凝结换热模型进行修正,修正后的计算结果与试验值基本吻合;采用RELAP5程序对垂直管内两相流自然循环传热进行计算,须选择热前沿跟踪模型。对非能动余热排出系统的稳态与瞬态运行特性进行分析,理论计算与试验结果均表明:稳态工况下,系统可以实现稳定的两相流自然循环,系统排热能力受蒸汽发生器水位的影响大,冷却水入口温度与系统压力的影响相对较小;系统的启动特性良好,可快速地建立环路的自然循环,带走反应堆的衰变热。     

套管式双面加热蒸汽发生器的热工水力分析

为研究套管式双面加热蒸汽发生器在稳态和瞬态过程中的热工水力特性，建立了描述蒸汽发生器物理现象的一维均匀流数学模型。应用该模型，开发了可计算稳态和瞬态工况下一回路和二回路冷却剂温度场、焓场的直流蒸汽发生器热工水力程序。计算结果对直流蒸汽发生器结构设计、运行具有指导意义。      

The Fort St. Vrain high temperature gas-cooled reactor: V. Steam system performance tests

The Fort St. Vrain primary and secondary coolant systems have given satisfactory performance during the rise to power test program with the tests being terminated at the current maximum allowable thermal reactor power of 70% of rated. Because of a regenerative heat problem in the steam generators, rated conditions of 1000°F main and hot reheat steam temperatures, predicted to occur at 25% power, were not reached until 68%. The regenerative heat problem also forced “overblowing” of the core with primary coolant helum which resulted in higher fuel temperatures than predicted, lower core primary coolant outlet temperatures and higher core primary coolant inlet temperatures. Data suggest that all parameters will be at rated conditions at 80–100% power. A small steam generator tubing leak was detected by the primary coolant moisture monitors of the plant protective system. It was located by covergas techniques and repaired by plugging the leaking feedwater and steam subheaders external to the reactor.     

Steady State and Transient Analysis of Novel Design Helium Cooled Ceramic Blanket (HCCB) System of China Fusion Engineering Test Reactor (CFETR)

An upgraded form of China fusion engineering test reactor (CFETR) was investigated for the safety performance. In the current study, modification of the designs were presented with relative tolerance. The steady state were calculated for the new design using Relap5 code. Two accidents were simulated i.e., in-vessel and In-box loss of coolant accident. These accidents were simulated in helium cooled ceramic blanket (HCCB) system for the purpose to investigate the safety measures of the CFETR. It is utmost important to ensure the safety performance of the reactor. In this research, sudden break at blanket system was assumed and calculated different parameters including temperature, pressure and coolant fluxes to observe the differences in pattern during the accident under limited time domain. The research is very important because the design of HCCB is new and there is a need to conduct steady state and transient state of the reactor in order to make sure and authenticate the design and to safer the reactor.     

The Fort St. Vrain high temperature gas-cooled reactor: X. Core temperature fluctuations

In October 1977, during the rise to power test program, the Fort St. Vrain high temperature gas-cooled reactor experienced the first of 37 fluctuation events involving primary coolant outlet temperature, nuclear detector signals, steam generator module gas inlet temperature and steam generator module main and reheat steam temperatures. In a 3 year investigation it was determined that the apparent cause of the fluctuations was movements of core components accompanied by periodic changes in bypass flows and crossflows of primary coolant helium. Installation of region constraint devices has eliminated fluctuations, but a single small primary coolant helium core outlet temperature redistribution is experienced routinely during rise to power.     

Diagnosis of steam generator by estimating an unobserved important state variable

In this study, a technique has been developed for diagnosing in on-line the state of the steam generator of the fast-breeder reactor (FBR) “Monju” by estimating an unobserved important state variable from observed data. The secondary coolant of liquid sodium faces to water/steam across a thin metal tube wall in the steam generator. Therefore, it is very important to detect a small anomaly of the wall of heat transfer tubes at an early stage. The aim of this study is to develop a technique for diagnosing in on-line a state of the steam generator by estimating an overall heat transfer coefficient, which is an unobserved important state variable, from observed data. This study shows simplified mathematical models of superheater and evaporator to estimate the overall heat transfer coefficient. The applicability of the technique is confirmed by configuring state observer with the mathematical model and noise filter and estimating using simulated data. As the results of the estimations, relative errors of the overall heat transfer coefficient of the superheater and the evaporator are less than ±0.5%.     

船用反应堆冷却剂泵连续调速研究

采用船用核动力装置模拟程序,对反应堆冷却剂泵转速连续调节研究进行仿真试验研究。在相同的40%满功率工况下,进行冷却剂泵转速阶跃变化与连续变化两种试验。对比了反应堆进出口温度、反应堆功率、反应堆反应性、冷却剂流量、蒸发器蒸汽压力等参数的变化情况,对开展船用反应堆冷却剂泵连续调速设计具有重要的指导意义。