A standard problem for HECTR-MAAP (Hydrogen Event: Containment Transient Responses-Modular Accident Analysis Program) comparison: In-cavity oxidation

Technical Report · Sun Oct 01 04:00:00 EDT 1989

DOI:https://doi.org/10.2172/5529585· OSTI ID:5529585

Wong, C. C. ^[1]

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1. Sandia National Labs., Albuquerque, NM (USA)

To assist in the resolution of differences between the NRC and IDCOR on the hydrogen combustion issue, a standard problem has been defined to compare the results of HECTR and MAAP analyses of hydrogen transport and combustion in a nuclear reactor containment. The first part of this problem, which addresses the question of deflagration in the upper and lower compartments, was presented in NUREG/CR-4993. The second part of this problem has been completed and is discussed in this report. This part addresses the issue of in-cavity oxidation of combustible gases produced by core-concrete interactions and the natural circulation between the reactor cavity and the lower compartment. HECTR analyses of the problem show that it is overly optimistic to assume a complete oxidation in the reactor cavity because a variety of phenomena, such as steam inerting and oxygen transport by natural convection, may influence the degree of in-cavity oxidation that takes place. An incomplete in-cavity oxidation will lead to accumulation and combustion of hydrogen and carbon monoxide in the lower and upper compartments in the reactor containment. This deflagration generates a peak pressure of 384.2 kPa (55.72 psia) at 7.36 hours. 20 refs., 38 figs., 2 tabs.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (USA). Div. of Systems Research; Sandia National Labs., Albuquerque, NM (USA)
• Sponsoring Organization: NRC
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5529585
• Report Number(s): NUREG/CR-5215; SAND--88-2260; ON: TI90001480
• Country of Publication: United States
• Language: English

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