Impact of accidents on organizational aspects of nuclear utilities

This paper applies the Beer Viable Systems Model (VSM) approach to the study of nuclear accidents. It relates how organizational structures and rules are affected by accidents in the attempt to improve safety and reduce risk. The paper illustrates this process with reference to a number of accidents. The dynamic cybernetic aspect of the VSM approach to organizations yields a better understanding of the need for good decision-making to minimize risk and how organizations really operate

Introduction to Nuclear Propulsion: Lecture 15 - Nuclear Test Operations

The test operation of nuclear power plants, specifically nuclear rockets, bears some interesting similarities to the operation of chemical rocket tests as well as, of course, many differences. A significant feature common to both nuclear and chemical rocket tests is that all the fuel for the entire operation is loaded at the start of the test. As a direct consequence of this fact, the operation of nuclear power plants must be surrounded with adequate safety precautions, as is indeed the case in the operation of chemical rockets, A second direct consequence is that in both types of testing a very thorough and complete checkout is made before starting the test

Restart time correlation for core annular flow in pipeline lubrication of high-viscous oil

One of the fundamental questions that must be addressed in the effective design and operation of pipeline lubrication of heavy oil is; “how much time will be needed to restart a blocked core annular flow (CAF) line after shutdown due to fouling or pump failures”, if the pipe is to be cleaned using water only. In this work, laboratory results of shutdown and restart experiments of high-viscous oil conducted in a 5.5-m-long PVC horizontal pipe with internal diameter of 26 mm are first presented. A new correlation for the prediction of the restart time of a shutdown core annular flow line is then formulated. The predictive capabilities of the correlation are checked against measured restart time and pressure drop evolution data. Somewhat high but still reasonable predictions are obtained. The restart time correlation, together with the associated correlations formulated as well, can be of practical importance during the engineering design of high-viscous oil pipeline transportation facility for predicting restart process

Applicability of 100kWe-class of space reactor power systems to NASA manned space station missions

An assessment is made of a manned space station operating with sufficiently high power demands to require a multihundred kilowatt range electrical power system. The nuclear reactor is a competitor for supplying this power level. Load levels were selected at 150kWe and 300kWe. Interactions among the reactor electrical power system, the manned space station, the space transportation system, and the mission were evaluated. The reactor shield and the conversion equipment were assumed to be in different positions with respect to the station; on board, tethered, and on a free flyer platform. Mission analyses showed that the free flyer concept resulted in unacceptable costs and technical problems. The tethered reactor providing power to an electrolyzer for regenerative fuel cells on the space station, results in a minimum weight shield and can be designed to release the reactor power section so that it moves to a high altitude orbit where the decay period is at least 300 years. Placing the reactor on the station, on a structural boom is an attractive design, but heavier than the long tethered reactor design because of the shield weight for manned activity near the reactor

The MOD-OA 200 kilowatt wind turbine generator design and analysis report

The project requirements, approach, system description, design requirements, design, analysis, system tests, installation safety considerations, failure modes and effects analysis, data acquisition, and initial performance for the MOD-OA 200 kw wind turbine generator are discussed. The components, the rotor, driven train, nacelle equipment, yaw drive mechanism and brake, tower, foundation, electrical system, and control systems are presented. The rotor includes the blades, hub and pitch change mechanism. The drive train includes the low speed shaft, speed increaser, high speed shaft, and rotor brake. The electrical system includes the generator, switchgear, transformer, and utility connection. The control systems are the blade pitch, yaw, and generator control, and the safety system. Manual, automatic, and remote control and Dynamic loads and fatigue are analyzed

Arctic Standards: Recommendations on Oil Spill Prevention, Response, and Safety in the U.S. Arctic Ocean

Oil spilled in Arctic waters would be particularly difficult to remove. Current technology has not been proved to effectively clean up oil when mixed with ice or when trapped under ice. An oil spill would have a profoundly adverse impact on the rich and complex ecosystem found nowhere else in the United States. The Arctic Ocean is home to bowhead, beluga, and gray whales; walruses; polar bears; and other magnificent marine mammals, as well as millions of migratory birds. A healthy ocean is important for these species and integral to the continuation of hunting and fishing traditions practiced by Alaska Native communities for thousands of years.To aid the United States in its efforts to modernize Arctic technology and equipment standards, this report examines the fierce Arctic conditions in which offshore oil and gas operations could take place and then offers a summary of key recommendations for the Interior Department to consider as it develops world-class, Arctic-specific regulatory standards for these activities. Pew's recommendations call for improved technology,equipment, and procedural requirements that match the challenging conditions in the Arctic and for full public participation and transparency throughout the decision-making process. Pew is not opposed to offshore drilling, but a balance must be achieved between responsible energy development and protection of the environment.It is essential that appropriate standards be in place for safety and for oil spill prevention and response in this extreme, remote, and vulnerable ecosystem. This report recommends updating regulations to include Arctic specific requirements and codifying temporary guidance into regulation. The appendixes to this report provide substantially more detail on the report's recommendations, including technical background documentation and additional referenced materials. Please refer to the full set of appendixes for a complete set of recommendations. This report and its appendixes offer guidelines for responsible hydrocarbon development in the U.S. Arctic Ocean

NUCLEAR POWER AND ELECTRIC GRID RESILIENCE: CURRENT REALITIES AND FUTURE PROSPECTS

Life as we know it in modern society relies on the smooth functioning of the electric Grid – the Critical Infrastructure system that generates and delivers electricity to our homes, businesses, and factories. Virtually all other Critical Infrastructure systems depend on the Grid for the electricity they require to execute other essential societal functions such as telecommunications, water supply and waste water services, fuel delivery, etc. This study examines the concepts of Critical Infrastructure and electric Grid resilience, and the role nuclear power plants do and might play in enhancing U.S. Grid resilience. Grid resilience is defined as the system’s ability to minimize interruptions of electricity flow to customers given a specific load prioritization hierarchy. The question of whether current U.S. nuclear power plants are significant Grid resilience assets is examined in light of this definition. Despite their many virtues and their “fuel security,” the conclusion is reached that current U.S. nuclear power plants are not significant Grid resilience assets for scenarios involving major Grid disruptions. The concept of a “resilient nuclear power plant” or “rNPP” – a nuclear power plant that is intentionally designed, sited, interfaced, and operated in a manner to enhance Grid resilience – is presented. Two rNPP Key Attributes and Six rNPP Functional Requirements are defined. Several rNPP design features (system architectures and technologies) that could enable a plant to achieve the Six rNPP Functional Requirements are described. Four specific applications of rNPPs are proposed: (1) rNPPs as flexible electricity generation assets, (2) rNPPs as anchors of hybrid nuclear energy systems, (3) rNPPs as Grid Black Start Resources, and (4) rNPPs as anchors of Resilient Critical Infrastructure Islands. The last two applications are new concepts for enhancing U.S. strategic resilience. Finally, a few key unresolved issues are discussed and recommendations for future research are offered. Study results support the overall conclusion that successful development and deployment of rNPPs could significantly enhance U.S. Grid, Critical Infrastructure, and societal resilience, while transforming the value proposition of nuclear energy in the 21st century

Dynamic Simulation and Testing To Assess Rundown Speed Of A Compressor

LecturesDynamic simulations are frequently conducted to verify the behavior of compressor stations during transient events. The most difficult situation to analyze is the event of an emergency shutdown, due to the very fast transients. Unfortunately, there is very little documented data that compares simulation results and the actual behavior of the station. We will evaluate available data sets for 3 different studies. The studies include a shutdown of a compressor against a closed recycle valve, a very well documented and published study on the emergency shutdown of a compressor in a test facility, and new data from a compressor station where a major station modification led to a dynamic simulation and subsequent verification. The latter will be described in some detail. The key finding is, that a difficulty, and a major source of inaccuracy lies in the correct prediction of the speed decay for the compressor