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Thermal analysis of the drywell for the Nuclear Material Storage Facility

Description: The Nuclear Materials Storage Facility Renovation Project has a conceptual design for the facility to store nuclear materials in containers inside drywells with passive cooling for long-term storage. The CFX thermal-hydraulic computer program was used to analyze internal heat-transfer processes by conduction, convection, and radiation with natural circulation of air by hydraulic buoyancy with turbulence and thermal stratification (TS) evaluated. A vertical drywell was modeled with 14 containers on support plates at 12-in. intervals. The TS of bay air outside the drywell increased the container maximum temperature by 0.728 F for each 1.0 F of bay-air TS from the bottom to the top of the drywell. The drywell outer-surface peak heat flux was shifted downward because of the effect of bay-air TS. An equivalent model was evaluated by the nodal-network conduction, convection, and radiation heat-transfer computer program (Thermal System Analysis Program) TSAP. The TSAP results are in good agreement with the CFX-model results, with the difference in results understood based on the approximations of each model.
Date: February 1, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Capacitance matrix method in TRAC and MELPROG

Description: The capacitance matrix method has been used in the TRAC and MELPROG transient, thermal-hydraulic, safety-analysis computer programs to solve the multi-dimensional-vessel matrix equations. A full-matrix solver rather than a more efficient banded-matrix solver was used previously because of nonzero elements lying outside the matrix bandwidth. These outlying nonzero elements result from vessel external and internal pipe flow channels connecting non-adjacent cells in the multidimensional vessel component. The capacitance matrix method provides a more efficient solution algorithm by solving the banded portion of the vessel-matrix equation with a banded-matrix solver. The effect of the nonzero outlying elements on that solution is accounted for through matrix algebra and a lower order capacitance-matrix equation solution that modifies the banded-matrix solution to give the full-matrix solution. 5 refs., 2 figs.
Date: January 1, 1989
Creator: Steinke, R.G. & Dearing, J.F.
Partner: UNT Libraries Government Documents Department

A description of the test problems in the TRAC-P standard test matrix

Description: This report describes 15 different test problems in the TRAC-P (Transient Reactor Analysis Code) standard test matrix of 42 test-problem calculations. Their TRACIN input-data files are listed in Appendix A. The description of each test problem includes the nature of what the test problem models and evaluates, the principal models of TRAC-P that the test problem serves to verify or validate, and the TRAC-P features and options that are being involved in its calculation. The test-problem calculations will determine the effect that changes made to a TRAC-P version have on the results. This will help the developers assess the acceptance of those changes to TRAC-P.
Date: March 1, 1996
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update FXTIME

Description: The DSTEP = {minus}99 and TIMET {ge} 0.0 s feature in TRAC-P has been tested on the W4LOOP and W4LOOPR standard test problems and was found to give different W4LOOPR solutions for different values of TIMET when all these cases should have given the same solution. Update FXTIME has corrected part of the cause of that difference and reduced the difference by an order of magnitude. The error associated with the remaining difference has been documented in Trouble Report 238.
Date: August 29, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update FXTPTM

Description: Knolls Atomic Power Laboratory reported that the trip-initiated, problem-termination feature was not functioning in TRAC-P, Version 5.4.15. A listing of the modified input data for the DRAIN standard test problem and the TRCMSG file output was provided that demonstrated that the TRAC-P calculation did not terminate when the problem-termination designated trip`s set status was set to ON{sub forward}. The assigned task was to investigate and correct this nonfunctioning feature in TRAC-P, Version 5.4.28. Update FXTPTM corrects a trip pointer error in subroutine TIMCHK that prevented the trip-initiated, problem-termination feature from functioning in TRAC-P.
Date: August 29, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update SUMNMULN

Description: New ``Sum N`` and ``Multiply N`` control blocks have been programmed by update SUMNMULN in TRAC-P Version 5.4.28. They define N signal variables and/or control blocks whose values are to be summed with optional weighting factors or multiplied, respectively.
Date: August 29, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update FXGRAV

Description: The Namelist-variable IELV = 1 option inputs ELEV cell-centered elevations for one-dimensional (1D) hydraulic and HTSTR components. TRAC-P then internally evaluates interface-centered GRAVs. TRAC-P checks that GRAVs evaluated from input ELEVs for the HTSTR component and GRAVs input directly under the Namelist-variable IELV = 0 option for 1D hydraulic and HTSTR components lie within the range of {minus}1.0 to 1.0. TRAC-P, however, does not check that GRAVs evaluated from ELEVs input for 1D hydraulic components lie in this range. Knolls Atomic Power Laboratory requested that TRAC-P Version 5.4.28 be programmed to perform this GRAV value check. Update FXGRAV checks that GRAVs evaluated from input ELEVs for one-dimensional hydraulic components lie in the value range of {minus}1.0 to 1.0.
Date: September 4, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update ZERORGH

Description: The one-dimensional (1D) hydraulic and three-dimensional (3D) VESSEL components in TRAC-P have in their motion (momentum) equations a {rho}{center_dot}g{center_dot}h gravity-head term where {rho} is the fluid phasic density, g is the acceleration-of-gravity constant (9.80665 m s{sup {minus}2}, 32.17405 ft s{sup {minus}2}), and h is the vertical elevation. Knolls Atomic Power Laboratory requested the capability to apply a Namelist-variable multiplier to the {rho}{center_dot}g{center_dot}h gravity-heat term in all motion equations of TRAC-P. The default value of this multiplier would be unity. Inputting zero would eliminate the effect of the {rho}{center_dot}g{center_dot}h gravity-head term in the motion equations. Update ZERORGH programs in the Namelist-variable multiplier FRGH to the {rho}{center_dot}g{center_dot}h gravity-head term in all motion equations of TRAC-P Version 5.4.28.
Date: September 4, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update FXFILL

Description: The FILL component in TRAC-P defines a phasic-velocities boundary condition or total-mass-flow boundary condition. FILL option IFTY = 10 defines the total-mass flow and its composition for flow donoring from the FILL to its adjacent component by signal variables and/or control blocks. For flow from the adjacent component to the FILL component, the phasic densities of the adjacent-component cell need to be upstream donored by the IFTY = 10 option total-mass flow. Instead, the FILL-cell phasic densities are being downstream donored incorrectly by the IFTY = 10 option total-mass flow in determining the FILL-junction phasic velocities. Using the wrong donored phasic densities caused the phasic velocities determined from the total-mass flow to be evaluated incorrectly. Five errors related to phasic-density donoring into a FILL- or BREAK-component cell are corrected by update FXFILL. Seven versions of a new test problem test these corrections and show that the errors of trouble reports 189 and 190 no longer exist in TRAC-P.
Date: September 2, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for update DTPCON

Description: Update DTPCON programs TRAC-P Version 5.4.28 with a Namelist variable IDTPC option to input 21 timestep-control parameter constants and 3 switch control variables. The 21 timestep-control parameter constants are a defined part of the internal timestep-size control criteria. The 3 switch control variables prevent a timestep reduction when the outer iteration fails to converge, when the timestep size needs to be reduced below DTMIN, and when a backup evaluation is to be performed.
Date: September 10, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Task completion report for investigating why output signal-variable values differ from their output component-parameter values in test problem MST2

Description: Signal-variable values and their component-parameter values differ in an end-of-timestep edit to the TRCOUT and TRCGRF files because signal variables have beginning-of-timestep values, and component parameters have end-of-timestep values. Oscillatory divergence in the MST2 standard test problem after 9000 s occurs because of TRAC-P`s numerical evaluation at a 1000 material Courant number. The magnitude of that divergence has diminished by a factor of 3.5 from Version 5.3.01 to 5.4.15 and by a factor of 25 from Version 5.4.15 to 5.4.28. That divergence can be eliminated by evaluating MST2 with a maximum material Courant number of 500.
Date: September 10, 1997
Creator: Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Thermal and flow analyses of the Nuclear Materials Storage Facility Renovation Title I 60% design

Description: The authors are continuing to use the computational fluid dynamics code CFX-4.2 to evaluate the steady-state thermal-hydraulic conditions in the Nuclear Material Storage Facility Renovation Title 1 60% Design. The analyses build on those performed for the 30% design. They have run an additional 9 cases to investigate both the performance of the passive vault and of an individual drywell. These cases investigated the effect of wind on the inlet tower, the importance of resolving boundary layers in the analyses, and modifications to the porous-medium approach used in the earlier analyses to represent better the temperature fields resulting from the detailed modeling of the boundary layers. The difference between maximum temperatures of the bulk air inside the vault for the two approaches is small. They continued the analyses of the wind effects around the inflector fixture, a canopy and cruciform device, on the inlet tower by running a case with the wind blowing diagonally across the inflector. The earlier analyses had investigated a wind that was blowing parallel to one set of vanes on the inflector. Several subcases for these analyses investigated coupling the analysis to the facility analysis and design changes for the inflector.
Date: August 1, 1998
Creator: Knight, T.D.; Steinke, R.G. & Mueller, C.
Partner: UNT Libraries Government Documents Department

Application programming interface document for the modernized Transient Reactor Analysis Code (TRAC-M)

Description: The objective of this document is to ease the task of adding new system components to the Transient Reactor Analysis Code (TRAC) or altering old ones. Sufficient information is provided to permit replacement or modification of physical models and correlations. Within TRAC, information is passed at two levels. At the upper level, information is passed by system-wide and component-specific data modules at and above the level of component subroutines. At the lower level, information is passed through a combination of module-based data structures and argument lists. This document describes the basic mechanics involved in the flow of information within the code. The discussion of interfaces in the body of this document has been kept to a general level to highlight key considerations. The appendices cover instructions for obtaining a detailed list of variables used to communicate in each subprogram, definitions and locations of key variables, and proposed improvements to intercomponent interfaces that are not available in the first level of code modernization.
Date: May 1, 1998
Creator: Mahaffy, J.; Boyack, B.E. & Steinke, R.G.
Partner: UNT Libraries Government Documents Department

Thermal and flow analysis of the Fluor Daniel, Inc., Nuclear Material Storage Facility renovation design (initial 30% effort of Title 1)

Description: The computational fluid dynamics code CFX4.2 was used to evaluate steady-state thermal-hydraulic conditions in the Fluor Daniel, Inc., Nuclear Material Storage Facility renovation design (initial 30% of Title 1). Thirteen facility cases were evaluated with varying temperature dependence, drywell-array heat-source magnitude and distribution, location of the inlet tower, and no-flow curtains in the drywell-array vault. Four cases of a detailed model of the inlet-tower top fixture were evaluated to show the effect of the canopy-cruciform fixture design on the air pressure and flow distributions.
Date: March 1, 1998
Creator: Steinke, R.G.; Mueller, C. & Knight, T.D.
Partner: UNT Libraries Government Documents Department

Task completion report for update FXCFM

Description: Update FXCFM corrects five areas of the TRAC-P choked-flow model that address TRAC-P Trouble Report items 235, 259, and 260. Knolls Atomic Power Laboratory, Marviken, Edwards, and Scientech critical-flow test problems were used to investigate the report errors and further errors that were found and to verify their correction.
Date: January 21, 1998
Creator: Steinke, R.G.; Lime, J.F.; Smith, R.J. & Steiner, J.L.
Partner: UNT Libraries Government Documents Department

TRAC code development status and plans

Description: This report summarizes the characteristics and current status of the TRAC-PF1/MOD1 computer code. Recent error corrections and user-convenience features are described, and several user enhancements are identified. Current plans for the release of the TRAC-PF1/MOD2 computer code and some preliminary MOD2 results are presented. This new version of the TRAC code implements stability-enhancing two-step numerics into the 3-D vessel, using partial vectorization to obtain a code that has run 400% faster than the MOD1 code.
Date: January 1, 1986
Creator: Spore, J.W.; Liles, D.R.; Nelson, R.A.; Dotson, P.J.; Steinke, R.G.; Knight, T.D. et al.
Partner: UNT Libraries Government Documents Department