A Poisson equation solver for rectangular or annular regions

King, Hartley H.

doi:10.1002/nme.1620100407

Cited by 5 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3-62, is currently written as fully implicit in both the spatial coordinates perpendicular and parallel to the shell surface. Direct solution techniques for discretization equations in two dimensions are available (King [79] ). However, when MELTSPREAD was originally developed, [1][2] these methods were deemed unacceptable due to the large computation time associated with these methods.…”

Section: Forward Elimination Solution Scheme: Melt Spreading Equationsmentioning

confidence: 99%

The MELTSPREAD Code for Modeling of Ex-Vessel Core Debris Spreading Behavior, Code Manual – Version3-beta

Farmer

2017

View full text Add to dashboard Cite

MELTSPREAD3 is a transient one-dimensional computer code that has been developed to predict the gravity-driven flow and freezing behavior of molten reactor core materials (corium) in containment geometries. Predictions can be made for corium flowing across surfaces under either dry or wet cavity conditions. The spreading surfaces that can be selected are steel, concrete, a user-specified material (e.g., a ceramic), or an arbitrary combination thereof. The corium can have a wide range of compositions of reactor core materials that includes distinct oxide phases (predominantly 2 , 2 , and steel oxides) plus metallic phases (predominantly Zr and steel). The code requires input that describes the containment geometry, melt "pour" conditions, and cavity atmospheric conditions (i.e., pressure, temperature, and cavity flooding information). For cases in which the cavity contains a preexisting water layer at the time of RPV failure, melt jet breakup and particle bed formation can be calculated mechanistically given the time-dependent melt pour conditions (input data) as well as the heatup and boiloff of water in the melt impingement zone (calculated). For core debris impacting either the containment floor or previously spread material, the code calculates the transient hydrodynamics and heat transfer which determine the spreading and freezing behavior of the melt. The code predicts conditions at the end of the spreading stage, including melt relocation distance, depth and material composition profiles, substrate ablation profile, and wall heatup. Code output can be used as input to other models such as CORQUENCH that evaluate long term core-concrete interaction behavior following the transient spreading stage.MELTSPREAD3 was originally developed to investigate BWR Mark I liner vulnerability, but has been substantially upgraded and applied to other reactor designs (e.g., the EPR), and more recently to the plant accidents at Fukushima Daiichi. The most recent round of improvements that are documented in this report have been specifically implemented to support industry in developing Severe Accident Water Management (SAWM) strategies for Boiling Water Reactors. This document is a Code Manual which contains i) a technology review, ii) descriptions of models and correlations, iii) descriptions of the implicit, finite difference numerical solution scheme, iv) a user's guide, and v) a summary of code validation calculations that have been performed to date.

show abstract

Section: Forward Elimination Solution Scheme: Melt Spreading Equationsmentioning

confidence: 99%

The MELTSPREAD Code for Modeling of Ex-Vessel Core Debris Spreading Behavior, Code Manual – Version3-beta

Farmer

2017

View full text Add to dashboard Cite

show abstract

“…Equation 10 was discretized at each grid point with the method of Patankar (1980) to yield a set of simulta- neous linear equations. With appropriate thermal conditions at the boundaries of the RUC, the temperature at each grid point was obtained from the solution of the set of simultaneous linear equations with the direct solution algorithm presented by King (1976).…”

Section: Microscopic Temperature Distributionsmentioning

confidence: 99%