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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
Eduardo V. Depiante, John E. Meyer
Nuclear Science and Engineering | Volume 104 | Number 2 | February 1990 | Pages 169-182
Technical Paper | doi.org/10.13182/NSE90-A23713
Articles are hosted by Taylor and Francis Online.
The analysis of transients in nuclear power plants is a complex problem normally requiring use of simulation tools. One of these tools, known as parity simulation, exploits the concept of electrical analogs of a physical system. Electrical analogs of the components of a nuclear plant are constructed and interconnected in a highly user-oriented facility known as a parity simulator. Parity simulation originated in the study of electronic network transients and spread to neutronic and single-phase flow applications. This work focuses on the application of parity simulation to transient thermal-hydraulic two-phase flow. The development of a two-phase flow element is described. The governing mass, momentum, and energy equations along with other conditions are applied to a pipe section. The resulting model is then used to construct a circuit analog. The proposed circuit analog requires nonstandard components, the design and implementation of which is discussed. Subsequently, a formulation for a steam generator is given. Results obtained for different cases are presented. Comparison with reference numerical solutions shows general agreement in both cases.