United States Nuclear Regulatory Commission - Protecting People and the Environment

Analysis of Ultimate-Heat-Sink Spray Ponds (NUREG-0733)

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Publication Information

Manuscript Completed: January 1981
Date Published:
August 1981

Division of Engineering
Office of Nuclear Reactor Regulation
U.S. Nuclear Regulatory Commission
Washington, DC 20555

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This report develops models which can be utilized in the design of certain types of spray ponds used in ultimate heat sinks at nuclear power plants, and ways in which the models may be employed to determine the design basis required by U.S. Nuclear Regulatory Commission Regulatory Guide 1.27.

The models of spray-pond performance are based on heat and mass transfer characteristics of drops in an environment whose humidity and velocity have been modified by the presence of the sprays. Drift loss from the sprays is estimated by a ballistics model.

The pond performance model is used first to scan a long-term weather record from a representative meteorological station in order to determine the periods of most adverse meteorology for cooling or evaporation. The identified periods are used in subsequent calculations to actually estimate the design-basis pond temperature. Additionally, methods are presented to correlate limited quantities of onsite data to the longer offsite record, and to estimate the recurrence interval of the design-basis meteorology chosen.

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