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ALICE: an arbitrary Lagrangian-Eulerian code for analyzing FBR containment response to HCDA

Description: This paper describes a reactor containment code, ALICE (Arbitrary Lagrangian-Eulerian Implicit-Explicit Containment Excursion code), which uses a hybrid Lagrangian-Eulerian finite-difference method for the treatment of the coolant motions and a Lagrangian finite-element technique for the analysis of the containment vessel and other solid media inside a reactor containment. The advantages of the ALICE code over the conventional Lagrangian or Eulerian method are: (1) the interpolations of the fluid and structural motions can be made very accurate as the cell vertices of the fluid adjacent to the structure moving with the structural nodal points; (2) the cells for the fluid calculation can be made in any quadrilateral shape corresponding to the perforated passageways or the structural deformation to avoid irregular-cell calculations; (3) inlet and outlet boundary conditions can be easily treated; (4) long-duration calculations can be achieved by rezoning the large distortion regions; and (5) a pure Lagrangian approach can be applied to those small distortion regions to treat flow problems with many materials. Two examples are given to illustrate the application of the ALICE code. The first one is a shock tube test in which an initial discontinuity of pressure and density is calculated. The second one is a SRI flexible-vessel test specially designed for the containment code validation. Results are discussed in detail.
Date: January 1, 1979
Creator: Chu, H.Y.
Partner: UNT Libraries Government Documents Department

Analysis of LMFBR containment response to an HCDA using a multifield Eulerian code. [MICE code]

Description: During a hypothetical core disruptive accident (HCDA), a core meltdown may cause the fuel cladding to rupture and the fuel fragments to penetrate into the sodium coolant. The heat in the molten fuel may cause the liquid sodium to boil, changing its phase. The interactions between materials are so complicated that a single-material model with homogenized material properties is not adequate. In order to analyze the above phenomena more realistically, a Multifield Implicit Continuous-Fluid Eulerian containment code (MICE) is being developed at Argonne National Laboratory (ANL) to solve the multifield fluid-flow problems in which the interpenetrations of materials, heat transfer, and phase changes are considered in the analysis. The hydrodynamics of the MICE code is based upon the implicit multifield (IMF) method developed by Harlow and Amsden. A partial donor-cell formulation is used for the calculation of the convective fluxes to minimize the truncation errors, while the Newton-Raphson method is used for the numerical iterations. An implicit treatment of the mass convection together with the equation of state for each material enables the method to be applicable to both compressible and incompressible flows. A partial implicit treatment of the momentum-exchange functions allows the coupling drag forces between two material fields to range from very weak to those strong enough to tie the fields completely. The differential equations and exchange functions used in the MICE code, and the treatment of the fluid and structure interactions as well as the numerical procedure are described. Two sample calculations are given to illustrate the present capability of the MICE code.
Date: January 1, 1977
Creator: Chu, H.Y. & Chang, Y.W.
Partner: UNT Libraries Government Documents Department

Evaluation of Lagrangian, Eulerian, and arbitrary Lagrangian-Eulerian methods for fluid-structure interaction problems in HCDA analysis

Description: The analysis of fluid-structure interaction involves the calculation of both fluid transient and structure dynamics. In the structural analysis, Lagrangian meshes have been used exclusively, whereas for the fluid transient, Lagrangian, Eulerian, and arbitrary Lagrangian-Eulerian (quasi-Eulerian) meshes have been used. This paper performs an evaluation on these three types of meshes. The emphasis is placed on the applicability of the method in analyzing fluid-structure interaction problems in HCDA analysis.
Date: January 1, 1979
Creator: Chang, Y.W.; Chu, H.Y.; Gvildys, J. & Wang, C.Y.
Partner: UNT Libraries Government Documents Department

Analysis of LMFBR primary system response to an HCDA using an Eulerian computer code

Description: Applications of an Eulerian code to predict the response of LMFBR containment and primary piping systems to hypothetical core disruptive accidents (HCDA), and to analyze sodium spillage problems, are described. The computer code is an expanded version of the ICECO code. Sample problems are presented for slug impact and sodium spillage, dynamics of the HCDA bubbles, and response of a piping loop. (JWR)
Date: January 1, 1975
Creator: Chang, Y.W.; Wang, C.Y.; Chu, H.Y.; Abdel-Moneim, M.T. & Gvildys, J.
Partner: UNT Libraries Government Documents Department