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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Nicolay Ivanov Kolev
Nuclear Technology | Volume 78 | Number 2 | August 1987 | Pages 95-131
Technical Paper | Fission Reactor | doi.org/10.13182/NT87-A33990
Articles are hosted by Taylor and Francis Online.
IVA 2/001 is a computer code for simulating transient, three-dimensional, three-phase, three-component nonhomogeneous (three velocity fields), nonequilibrium flow in a cylindrical porous body (including nuclear reactor cores if desired). Each velocity field consists of an inert and a noninert component. A separated equation of field mass, inert mass concentration in each of the fields, and entropy of the fields together with mixture momentum equations for the flow are solved by a semi-implicit numerical method with an analytical reduction to the pressure or pressure velocity problem and backward substitution. The flexibility of the method in describing three velocity fields of arbitrary direction is demonstrated. The solution procedure of the hydrodynamic problem is described. Finally, a numerical example and a comparison with experimental data demonstrate that the IVA2 method is a powerful tool for numerical multiphase flow simulation.
