Reactor Development focuses on improving the power, capability, reliability, and endurance of naval reactors.

Improvements are

effected through the design and development of advanced reactor concepts and components and through incorporation of new reactor fuels and materials. Experience with operating reactors and examination of spent cores are also used in developing and evaluating technology to improve reactor performance.

To support present and future reactor plant advances there must be a continuing reactor design effort coupled with analysis of operating reactors. The overall design objective is to improve plant performance by increasing the power capability and

endurance of naval reactor cores.

The Advanced Fleet Reactor will provide the improved plant performance necessary for the next generation of nuclear powered submarines. The Advanced Fleet Reactor will have a higher power core in addition to incorporating the latest advanced quieting techniques. Also, design efforts are underway to make this plant simpler and more reliable, giving it more operational flexibility.

Development of advanced materials and fuels is instrumental in improving the power and endurance of a naval reactor. Increasing core performance heightens the need for advanced materials and for advanced analytical models to optimize core designs and arrangements. New fuels, poisons, and materials are developed

and tested in operating reactor plant environments to confirm their suitability for naval application.

To test the most promising possibilities, two prototype cores are under development. The Submarine Test Core will be used to test

improved reactor fuels and various cladding techniques using different materials and manufacturing treatments. The Developmental Materials Core will test further advances in fuel concepts and, in addition, will provide the means for evaluation of new poisons and advanced design equipment for controlling reactor performance.

Proving out new concepts and designs involves fabrication of reactor plant cores and components for installation, operation and testing in prototype reactor plants to ensure conformance

about core performance and the effects of reactor operation on materials. Information gained from these examinations is vital

to improving the performance of new cores.

Combining this

information, sound analysis, and new developments in reactor technology ensures optimal performance and safety.

During FY 1985, Reactor Development work will include: the continuation of the design effort for the Advanced Fleet Reactor, preproduction of fuel elements, and fuel assemblies, analysis and fabrication of major components such as the core barrel, closure head and control drive mechanisms, and intensive thermal, mechanical, and noise testing and analysis; analysis and development work required for the installation of the Submarine Test Core and completion of physics acceptance and certification testing; and continued work on the Developmental Materials Core.

In addition, work will also include: examination of expended cores and irradiated test specimens; evaluation of material corrosion behavior; continued development of the Modified Fuel Process; and continued qualification of noise and vibration design procedures and noise and vibration testing of prototypic

components.

Capital Equipment

Capital equipment required for Fiscal Year 1985 provides for the upgrading and replacement of laboratory and prototype plant equipment, components, and systems, such as reactor control,

instrumentation and monitoring systems; quality assurance

equipment; laboratory analytical and test equipment; and safety equipment.

Construction

Construction funds are requested in FY 1985 to continue two projects: the Materials Facility, project number 82-N-111, which will provide a second source for manufacture of naval nuclear fuel and is in its fourth year of funding; and the Modifications and Additions to Prototype Facilities, project number 81-T-112, which will modify and add engineered safety features to several prototype propulsion plants and is in its fifth year of funding.

II. PLANT DEVELOPMENT

Plant Development provides for improving reactor plant capability exclusive of the reactor itself, with primary emphasis on improving plant reliability and performance, increasing ease of plant operation and maintenance, and improving plant shock resistance. The work is important because propulsion plant characteristics cannot be improved solely through work on the reactor. To realize any significant increase in overall propulsion plant capability, plant development work must progress hand in hand with advances in reactor technology.

Principal efforts include the development of improved plant components and systems, alternate plant structural materials, improved material processing treatment methods to reduce corrosion, and new methods for chemistry treatment and water purification. The component and system development effort encompasses primary plant fluid, mechanical, and electrical systems and instrumentation, reactor plant control systems and components; and primary and secondary plant components.

A sound understanding of the properties and characteristics of various materials and water chemistries is vital to determining the efficiency and reliability of a reactor plant. A comprehensive testing and evaluation effort selects candidate materials having improved corrosion, fatigue and wear characteristics. Water chemistry and purification work is done to determine methods having the least adverse effect while keeping the coolant as free from corrosion products as possible.

In FY 1985, Naval Reactors will continue Plant Development efforts including: development, testing, and evaluation of reactor plant components and component materials such as improved power supplies; plant analyses to develop and maintain operating and casualty procedures; testing of various steam generator servicing techniques; testing of improved water chemistry treatments; the design of microprocessor-based instrumentation and control equipment; and operating multi-purpose test facilities for use in evaluating problems and improving plant performance.

III. REACTOR OPERATION AND EVALUATION

Reactor Operation and Evaluation involves the operation, servicing, upgrading, and testing of the eight land-based

prototype nuclear propulsion plants. These prototypes are operated to test developmental concepts, components and cores for naval nuclear propulsion plants, and are fully instrumented to provide data needed for the evaluation of reactor plant equipment.

A great deal of testing of individual materials, components and systems is done, leading to the selection of the most promising for incorporation into a prototype plant. Only in the operating prototype plants can actual in-service conditions be duplicated