Engineering topics

Muhlheim, Michael David

Publications and source records attributed to Muhlheim, Michael David.

5 records

DOE OSTI2018

Licensing Challenges Associated with Autonomous Control

Very small special purpose reactors (SPRs), or microreactors at less than 50 MW electric, are under consideration by various entities for applications in remote installations and communities. These entities include remote municipalities, the US Department of Defense (DoD), and the US Department of Energy (DOE). SPRs or microreactors may be transportable from a factory with fresh fuel included to serve as a complete power battery. This type of plug-and-go resource requires inherently positive safety attributes and robust design. SPRs and microreactors are being designed to fulfill black-start or microgrid capabilities and to provide protection against severe natural phenomena or cyber security threats. These reactors would be available to operate for several years without a need to shut down for refueling.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2018

A survey of additive manufacturing capabilities

A previous ORNL report [1] focused on early AM material considerations for reactor technologies and provided some initial licensing considerations. The current report is a complement to the previous report, providing a survey of AM capabilities that could be used to manufacture SPR SSCs. Specific reactor use cases and overviews of various reactor types are not included in this report.

36 MATERIALS SCIENCE↗

DOE OSTI2018

A survey of materials for additive manufacturing

Very small special purpose reactors (SPRs) are under consideration by various entities for remote installations and communities. This type of plug-and-go resource requires inherently positive safety attributes and sound design. Such reactors may be transportable with fresh fuel to serve as a complete power “battery” and they may even be transportable on short notice after initial use. SPRs could eliminate costly and in some cases dangerous fossil fuel deliveries. Small passively safe reactors could be operated remotely by an offsite operations crew. While use cases for such reactors are currently under development, advanced manufacturing processes should be considered to support reactor economics.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

DOE OSTI2017

Assessment of Applicability of Standards Endorsed by Regulatory Guides to Sodium Fast Reactors

The benefits of the use of voluntary consensus standards and industry standards is evident in the design and licensing of the current generation of nuclear power plants. The use of voluntary consensus standards and industry standards would be helpful in the design and licensing of advanced reactors to improve the effectiveness and efficiency of the licensing and regulation of non-LWR technologies. Most of the regulations, guidance, and standards applicable to nuclear power plants were developed for water-cooled plants, so they may not adequately address the coolants, materials, temperatures, operations, testing, maintenance, etc., proposed for advanced reactors.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2017

Operational Performance Risk Assessment in Support of A Supervisory Control System

Supervisory control system (SCS) is developed for multi-unit advanced small modular reactors to minimize human interventions in both normal and abnormal operations. In SCS, control action decisions made based on probabilistic risk assessment approach via Event Trees/Fault Trees. Although traditional PRA tools are implemented, their scope is extended to normal operations and application is reversed; success of non-safety related system instead failure of safety systems this extended PRA approach called as operational performance risk assessment (OPRA). OPRA helps to identify success paths, combination of control actions for transients and to quantify these success paths to provide possible actions without activating plant protection system. In this paper, a case study of the OPRA in supervisory control system is demonstrated within the context of the ALMR PRISM design, specifically power conversion system. The scenario investigated involved a condition that the feed water control valve is observed to be drifting to the closed position. Alternative plant configurations were identified via OPRA that would allow the plant to continue to operate at full or reduced power. Dynamic analyses were performed with a thermal-hydraulic model of the ALMR PRISM system using Modelica to evaluate remained safety margins. Successful recovery paths for the selected scenario are identified and quantified via SCS.

Denning, Richard S.↗