聚变中子源驱动的次临界清洁核能系统──聚变能技术的早期应用途径

提出作为聚变能技术早期应用途径的聚变中子源驱动的清洁核能系统概念,并从国家的能源需求、国内外核电发展状况论述开发这种系统的必要性和意义,根据国内外聚变驱动器技术及次临界包层技术进展和国内多年的可行性研究结果,说明开发这种系统的现实性和基础。文中也给出了建议的发展进程。     

核聚变研究50年

分析了国内外核聚变研究成果现状和发展的趋势 ,对国民经济发展过程中的能源需求作了预测 ,对中国的聚变能源战略和历史机遇 (经济、技术体系、地位 )作了讨论 ,介绍了聚变 裂变混合堆并提出了发展聚变 裂变混合堆的总体设想、研究内容和预期目标。     

聚变堆氚分析程序TAS1.0的设计与开发

氚是聚变堆的重要燃料之一,对聚变堆氚系统进行分析从而实行有效的氚控制是聚变研究的重要内容之一.在中国系列液态金属锂铅包层聚变堆概念设计研究基础上,利用现代软件工程方法及面向对象技术设计思想,发展了聚变堆氚分析程序TAS1.0,可用于聚变堆氚自持分析、氚燃料管理及氚安全性分析与研究,并可为聚变堆包层及燃料循环系统设计与分析提供技术支持.通过一系列的测试校验,表明了该程序的正确性与有效性.本文主要介绍该程序的系统设计、技术特点与程序测试.     

聚变-裂变燃料工厂概念设计

报道了正在进行的一项聚变-裂变燃料工厂的概念设计计划,它的主要内容是进行参量系统的分析和进行一些关键性的实验与技术研究,并通过这些研究来探讨在中国建立聚变-裂变燃料工厂来支持PWR核电站的必要性和技术可行性,为下世纪初在中国建立一座实验性的聚变-裂变混合堆作可行性和方案性研究。已有的研究表明,在现有物理与技术基础之上,已有可能建成有意义的,以生产裂变燃料为主的聚变-裂变混合堆。     

评价聚变研究的新方向

在过去40年中，预测的聚变主要应用是总电站和电厂。但那时预测的扩大未来电力需求的规模至今还未实现。只用煤做燃料的火力发电厂的发电能力增加了。每年增加3%（年度能源形势，1998）^[1]。同样，利用聚变传送节能电的能力还没有可靠的条件，论证极少。这两个因素阻碍了聚变能的商业化。现在是重新评价聚变能会给全世界带来什么最好的东西的时候了。聚变，一种取之不尽，用之不竭的能源，具有许多独特性，能用于各种有益的产品。ARIES工作小组正在进行一项研究，考察聚变可能有哪些用途，评价那些有潜力提供有用的、有价值的最新产品的用途。他们研制出一种聚变可能性用途的工作图，用以评价如何利用聚变过程的独有特性。潜力产品划分为能量生产（燃料、电力、热力）、空间推进器、被改变或改性的材料特性（嬗变、废物处理、氚生产、化合物的分解（废物的处理、矿石还原、提炼）、聚变核产物的直接利用（X射线照射、刻印、放射疗法、活化分析）。根据以前各种大型的国内、国际技术开发项目的成功与失败经验，改进了评估方法以便评价和建议令人鼓舞的聚变产品的应用。制定了一份可以描述和形成有特色的项目的重要属性清单，这些项目在全球市场中有可能成功、也有可能失败。这此属性是根据它们在国内或全球企业中被发掘的价值来确定其份量的。利用附加的应用理论方法定量评价了聚变在市场潜力、环境问题、经济影响、风险和公众感受等方面提出的作用。确认了每一种聚变潜在的用途和市场需求达标的数据，为今后能源的分配作出更加明智的决策。在1997年12月召开的东京气候变化会议中提出了合并一些长期市场发展趋势，发现其中最被看好的聚变应用是氢燃料的生产、核废物的嬗变和化合物的分解。所有这些都略领先于电力生产。从该决策分析过程得到的结论将有助于平衡成功与失败之间的利益冲突，从而有助于为今后的研究选择有开发前景的产品。     

聚变—裂变混合堆及其在我国核能发展中的作用

本文概要介绍聚变和聚变-裂变混合堆基本原理及其作用。聚变-裂变混合堆可以为压水堆或快堆提供充足的核燃料。它和压水堆或快堆组成的系统具有经济可行性。在解决我国核能发展中燃料短缺问题和促进纯聚变能源的发展方面可望发挥重要的作用。     

关于聚变能源历史的回顾及其对未来的意义

历史证明，所有推进聚变研究的重要机遇都是重要的外部事件－－通常是全球性事件的结果。项目经历的下降也是如此。科学成就本身还不足以支持对聚变能主要和持续发展需求的支持。项目的科技进步产生了一时追加的支持，当遇到资金削减的时候，也许能够帮助项目的预算有一个下限。当一个机会到来时，项目准备状态的平衡和程度对决定它好转或下降的程度起关键作用。从历史中吸收的主要经验是，作为一项政策，聚变研究界应当组织其项目对重要的意想不到的外部事件作出有效反应。这意味着聚变界必须致力于那些经常有竞争性的愿望之间达到一种所罗门式的平衡，这些愿望包括：获得对聚变级等离子体基础的进一步理解；证明最优的磁约束和惯性约束位形；证明在燃烧等离子体条件下的性能；发展和证明一个有吸引力和实用的聚变能源系统所需的技术和设计。获得对使用“平衡”和“时刻准备”两项原则的支持是今后决策的关键。1997年，惯性约束聚变项目显示，它已经准备好利用一个重要的机会，即停止地下核武器试验的决定和全面禁止试验条约的考虑所提价匠机会。聚变能源科学界同样应当为它在过去五年里，将自己改造成为有发展前景和稳定的企业而感到无比的自豪，尽管有时伴随着相当的痛苦，持续做下去是每个人的任务。     

苏联激光聚变研究

【美国《聚变技术》1988年9月号第253页报道】本文回顾了苏联激光聚变研究25年的历史,对聚变研究采取的重大步骤、建造大型激光装置和以实验结果为依据的理论预言进行了讨论。60年代初,人们提出了利用激光把等离子体加热到热核反应温度的想法,并在1961年苏联科学院年会上作了介绍,1963年又在法国巴黎举行的第五届量子电子学国际会议     

通向惯性聚变能的战略

对惯性聚变的向心聚爆物理过程的认识及技术的进展已把我们带向惯性聚变研究的崭新阶段：着手建造有点火能力的激光装置「美国国家点火装置（ＮＩＦ）和法国兆焦耳计划（ＦＭＰ）」。一旦在这批点火级装置上成功演示了点火和增益，这也会导致我们考虑惯性聚变能（ＩＦＥ）研究的新阶段，即着手于在高脉冲率下运行的ＩＦＥ实验装置。为了弄清获得技术和经济可行性的关键问题，已研究了许多ＩＦＥ电厂设计概念。对于直接和间接驱动方案     

磁约束聚变“点火”装置中聚变中子测量

概述了大、中型托卡马克在D-D和D-T运行条件下聚变中子能谱和强度的测量的最新方法;推介了几种最新的聚变中子探测器和能谱仪及活化分析方法;评估了各种聚变中子探测器和能谱仪的优势,适用的范围和技术方面的局限性。对即将建成的HL-2A(中环流器二号A型)托卡马克的聚变中子的泄漏能谱和辐射强度的时、空分辨测量以及研究聚变中子在通过中子倍增剂过程中的能谱变化,在探测器方面提供了几种可供选择的技术方案。     

A Fusion Neutron Source Driven Sub-Critical Nuclear Energy System: A Way for Early Application of Fusion Technology

1. IntroductionAlthough the recent experiments and associatedtheoretical studies of fusion energy development havedemonstrated the feasibility of fusion power, it iscommonly realized that it needs hard work beforepure fusion energy could be commercially and eco-nomically utilized. On the other hand, the fissionnuclear industry has been falling on hard tithes re-cently since so far there has been no conclusion abouthow to deal with the long-lived wastes produced fromthe nuclear spent fuel and a…     

The fusion breeder concept

Some practical aspects and broader consequences of strategies that have been proposed for the association of fusion and fission processes are reviewed.It is concluded more particularly that the build-up of the technology necessary for the ultimately desired substitution of fusion for the present fission source of nuclear power could be much advanced by an interim period of the application of fusion entirely to the breeding of U-233 for the large number of fission reactors that will be coexisting during this period.Principal reasons for this view are the considerable technical easements of this approach, and the very large gain in effective energy release per fusion event, which offers economic advantage long before achievement of the classic definition of the fusion “break even” point.     

Transmutation missions for fusion neutron sources

There are a number of potential neutron transmutation missions (destruction of long-lived radioisotopes in spent nuclear fuel, ‘disposal’ of surplus weapons-grade plutonium, ‘breeding’ of fissile nuclear fuel) that perhaps best can be performed in sub-critical nuclear reactors driven by a neutron source. The requirements on a tokamak fusion neutron source for such transmutation missions are significantly less demanding than for commercial electrical power production. A tokamak fusion neutron source based on the current physics and technology database (ITER design base) would meet the needs of the spent nuclear fuel transmutation mission; the technical issue would be achieving ≥50% availability, which would require advances in component reliability and in steady-state physics operation.     

A fusion–fission hybrid reactor with water-cooled pressure tube blanket for energy production

A fusion–fission hybrid reactor is proposed to achieve the energy gain of 3000 MW thermal power with self-sustaining tritium. The hybrid reactor is designed based on the plasma conditions and configurations of ITER, as well as the well-developed pressurized light water cooling technologies. For the sake of safety, the pressure tube bundles are employed to protect the first wall from the high pressure of coolant. The spent nuclear fuel discharged from 33GWD/tU Light Water Reactors (LWRs) and natural uranium oxide are taken as driver fuel for energy multiplication. According to thermo-mechanics calculation results, the first wall of 20 mm is safe. The radiation damage analysis indicates that the first wall has a lifetime of more than five years. Neutronics calculations show that the proposed hybrid reactor has high energy multiplication factor, tritium breeding ratio and power density; the fuel cannot reach the level of plutonium required for a nuclear weapon. Thermal-hydraulic analysis indicates that the temperatures of the fuel zone are well below the limited values and a large safety margin is provided.     

Coherent fusion theory

We propose that energy from nuclear fusion reactions can be coupled to a macroscopic system coherently (in the laser sense) through electromagnetic interaction of low energy photons. We report progress on the formulation of a theory for two-step reactions in which virtual fusion is followed by exothermic incoherent decay. A new type of reaction in which incoherent electron capture is followed by coherent fusion is described.     

Neutron Excess Generation by Fusion Neutron Source for Self-Consistency of Nuclear Energy System

The present day fission energy technology faces with the problem of transmutation of dangerous radionuclides that requires neutron excess generation. Nuclear energy system based on fission reactors needs fuel breeding and, therefore, suffers from lack of neutron excess to apply large-scale transmutation option including elimination of fission products. Fusion neutron source (FNS) was proposed to improve neutron balance in the nuclear energy system. Energy associated with the performance of FNS should be small enough to keep the position of neutron excess generator, thus, leaving the role of dominant energy producers to fission reactors. The present paper deals with development of general methodology to estimate the effect of neutron excess generation by FNS on the performance of nuclear energy system as a whole. Multiplication of fusion neutrons in both non-fissionable and fissionable multipliers was considered. Based on the present methodology it was concluded that neutron self-consistency with respect to fuel breeding and transmutation of fission products can be attained with small fraction of energy associated with innovated fusion facilities.     

Preliminary design of hybrid energy reactor and integral neutron experiments

We propose a preliminary design for a fusion–fission hybrid energy reactor (FFHER), based on current fusion science and technology (with some extrapolations forward from ITER) and well-developed fission technology. We list design rules and put forward a primary concept blanket, with uranium alloy as fuel and water as coolant. The uranium fuel can be natural uranium, LWR spent fuel, or depleted uranium. The FFHER design can increase the utilization rate of uranium in a comparatively simple way to sustain the development of nuclear energy. We study the interaction between the fusion neutron and the uranium fuel with the aim of to achieving greater energy multiplication and tritium sustainability. We also review other concept hybrid reactor designs. We design integral neutron experiments in order to verify the credibility of our proposed physical design. The combination of this program of research with the related thermal hydraulic design, alloy fuel manufacture, and nuclear fuel cycle programs provides the science and technology foundation for the future development of the FFHER concept in China.     

A strategic framework for the magnetic fusion energy program

Fusion is recognized as a sufficiently abundant and environmentally attractive energy source to sustain industrial society in the 21st century and beyond. This paper outlines a strategic framework for the U.S. magnetic fusion program that builds substantially on the high-quality research and the strong scientific and technological basis that has been established during the past two decades.     

The fusion-supported decentralized nuclear energy system

A decentralized nuclear energy system is proposed comprising mass-produced pressurized water reactors in the size range 10 to 300 MW (thermal), to be used for the production of process heat, space heat, and electricity in applications where petroleum and natural gas are presently used. Special attention is given to maximizing the refueling interval with no interim batch shuffling in order to minimize fuel transport, reactor downtime, and opportunity for fissile diversion. The smallest reactors could be deployed as nuclear batteries, kept in the equivalent of spent-fuel shipping casks and returned to nuclear fuel centers for refueling. These objectives demand a substantial fissile enrichment (7 to 15%). The preferred fissile fuel is U-233, which offers an order of magnitude savings in ore requirements (compared with U-235 fuel), and whose higher conversion ratio in thermal reactors serves to extend the period of useful reactivity and relieve demand on the fissile breeding plants (compared with Pu-239 fuel). Application of the neutral-beam-driven tokamak fusion-neutron source to a U-233 breeding pilot plant is examined. This scheme can be extended in part to a decentralized fusion energy system, wherein remotely located large fusion reactors supply excess tritium to a distributed system of relatively smallnonbreeding D-T reactors.