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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
Wolfgang Wulff
Nuclear Technology | Volume 159 | Number 3 | September 2007 | Pages 292-309
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3877
Articles are hosted by Taylor and Francis Online.
The paper presents integral methods for simulating two-phase flow transients in complex cooling systems, such as those in nuclear power plants. The methods are designed to simplify presently prevailing thermohydraulics simulation methods without a loss in simulation fidelity. The paper describes the inherent, but unnecessary, complexity of currently used simulation models, explains their inherent shortcomings, and foretells the impact of current code development trends on future capabilities to resolve safety issues in light of growing code complexities and inflexibility. The purpose of the paper is to present simpler alternatives.Integral methods described in the paper facilitate flexibility via computer-automated modularity and simplicity. They provide transparency through analytical methods. Integral methods replace partial by ordinary differential equations and thereby simplify the mathematical model formulation and achieve numerical integration with minimal numerical damping. The models connect important physical characteristic response times with the time step for numerical integration. The mixture model of nonhomogeneous, nonequilibrium two-phase flow, the integral of the volumetric flux divergence equation, and the integrals of the system of coupled loop momentum balances for interconnected loops in complex thermohydraulic systems play central modeling roles. A new and compact formulation of these equations facilitates a computerized system assembly of component models, each one being judiciously selected from a model library to impose the minimum necessary complexity. The method of assembly is based on linear algebra and accommodates any combination of phasic flow directions anywhere in the hydraulic system and at any time.