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Latest News
DOE announces NEPA exclusion for advanced reactors
The Department of Energy has announced that it is establishing a categorical exclusion for the application of National Environmental Policy Act (NEPA) procedures to the authorization, siting, construction, operation, reauthorization, and decommissioning of advanced nuclear reactors.
According to the DOE, this significant change, which goes into effect today, “is based on the experience of DOE and other federal agencies, current technologies, regulatory requirements, and accepted industry practice.”
A.M. Hassanein
Fusion Science and Technology | Volume 15 | Number 2 | March 1989 | Pages 513-521
Plasma Engineering | doi.org/10.13182/FST89-A39751
Articles are hosted by Taylor and Francis Online.
Melting and vaporization of metallic reactor components such as the first wall and the limiter/divertor may be expected in fusion reactors due to the high energy deposition resulting from plasma instabilities occuring during both normal and off-normal operating conditions. Off-normal operating conditions result from plasma disruptions where the plasma loses confinement and dumps its energy on parts of reactor components. High heat flux may also result during normal operating conditions due to fluctuations in plasma edge conditions. The net erosion rates resulting from both melting and vaporization are very important in estimating the lifetime of such reactor components. Of particular significance is the stability and erosion of the resulting melt layer which directly impacts the total expected lifetime of the reactor. During the course of the disruption, the melt layer may be exposed to various forces such as electromagnetic, gravitational, plasma debris momentum, vapor recoil, surface tension and other forces. The loss of the melt layer during the disruption could have a serious impact on the required safe and economic operation of the reactor. A model is developed to describe the behavior of the melt layer during the time evolution of the disruption. The analysis is done parametrically for a range of disruption times, energy densities and various acting forces.