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Justine user`s manual

Description: Justine is the graphical user interface to the Los Alamos Radiation Modeling Interactive Environment (LARAMIE). It provides LARAMIE customers with a powerful, robust, easy-to-use, WYSIWYG interface that facilitates geometry construction and problem specification. It is assumed that the reader is familiar with LARAMIE, and the transport codes available, i.e., MCNPTM and DANTSYSTM. No attempt is made in this manual to describe these codes in detail. Information about LARAMIE, DANTSYS, and MCNP are available elsewhere. It i also assumed that the reader is familiar with the Unix operating system and with Motif widgets and their look and feel. However, a brief description of Motif and how one interacts with it can be found in Appendix A.
Date: October 1, 1995
Creator: Lee, S.R.
Partner: UNT Libraries Government Documents Department

Three-dimensional Computational Fluid Dynamics (CFD) modeling of dry spent nuclear fuel storage canisters

Description: One of the interim storage configurations being considered for aluminum-clad foreign research reactor fuel, such as the Material and Testing Reactor (MTR) design, is in a dry storage facility. To support design studies of storage options, a computational and experimental program was conducted at the Savannah River Site (SRS). The objective was to develop computational fluid dynamics (CFD) models which would be benchmarked using data obtained from a full scale heat transfer experiment conducted in the SRS Experimental Thermal Fluids Laboratory. The current work documents the CFD approach and presents comparison of results with experimental data. CFDS-FLOW3D (version 3.3) CFD code has been used to model the 3-dimensional convective velocity and temperature distributions within a single dry storage canister of MTR fuel elements. For the present analysis, the Boussinesq approximation was used for the consideration of buoyancy-driven natural convection. Comparison of the CFD code can be used to predict reasonably accurate flow and thermal behavior of a typical foreign research reactor fuel stored in a dry storage facility.
Date: June 1, 1997
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Thermal analysis modeling and simulation of spent nuclear fuel canister using CFDS-FLOW3D

Description: The computational fluid dynamics (CFD) code CFDS-FLOW3D (version 3.3) has been utilized to model a three-dimensional thermal analysis of the spent nuclear fuel dry storage mockup test. The Experimental Thermal-Fluids (ETF) group obtained experimental data to benchmark computer codes for verifying the dry storage of aluminum-clad spent nu clear fuel. This report provides CFDS-FLOW3D detailed predictions and benchmark, against the test data. Close comparison of the computational results with the experimental data provide verification that the code can be used to predict reasonably accurate convective flow and thermal behavior of a typical foreign research reactor fuel, such as the Material and Testing Reactor (MTR) design tested, while stored in a dry storage facility.
Date: April 1, 1995
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities

Description: The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geological codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geological repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.
Date: January 13, 1999
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Thermal Performance Analysis of Repository Codisposal Waste Packages Containing Aluminum-Clad Spent Nuclear Fuel

Description: The leading codisposal waste package (WP) design proposes that a central DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF) canister be surrounded by five defense waste process facility (DWPF) glass log canisters, and placed into a WP in the Mined Geologic Disposal System (MGDS).
Date: February 19, 1999
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Transient Accident Analysis of the Glovebox System in a Large Process Room

Description: Local transient hydrogen concentrations were evaluated inside a large process room when the hydrogen gas was released by three postulated accident scenarios associated with the process tank leakage and fire leading to a loss of gas confinement. The three cases considered in this work were fire in a room, loss of confinement from a process tank, and loss of confinement coupled with fire event. Based on these accident scenarios in a large and unventilated process room, the modeling calculations of the hydrogen migration were performed to estimate local transient concentrations of hydrogen due to the sudden leakage and release from a glovebox system associated with the process tank. The modeling domain represented the major features of the process room including the principal release or leakage source of gas storage system. The model was benchmarked against the literature results for key phenomena such as natural convection, turbulent behavior, gas mixing due to jet entrainment, and radiation cooling because these phenomena are closely related to the gas driving mechanisms within a large air space of the process room. The modeling results showed that at the corner of the process room, the gas concentrations migrated by the Case 2 and Case 3 scenarios reached the set-point value of high activity alarm in about 13 seconds, while the Case 1 scenario takes about 90 seconds to reach the concentration. The modeling results were used to estimate transient radioactive gas migrations in an enclosed process room installed with high activity alarm monitor when the postulated leakage scenarios are initiated without room ventilation.
Date: January 11, 2008
Creator: Lee, S.
Partner: UNT Libraries Government Documents Department

Design Analysis for a Scaled Erosion Test

Description: In support of a slurry wear evaluation in the pretreatment filtration and evaporation systems of RPP-WTP, Engineering Modeling and Simulation Group (EMSG) has developed the computational models to help guide component design and scaling decisions and to assist in the full-scale analyses. This report deals with the filtration system. In this project, computational fluid dynamics (CFD) methods were applied to ensure that the test facility design would capture the erosion phenomena expected in the full-scale cross-flow ultrafiltration facility. The literature survey was initially performed to identify the principal mechanisms of erosion for a solids laden fluid.
Date: April 10, 2002
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Erosion Analysis for the Misaligned U2 Nozzle and its Connector Block

Description: In support of an erosion evaluation for the misaligned mating surfaces of the U2 nozzle and its connector block in the 3H evaporator lift-separator jumper, the Engineering Modeling and Simulation Group (EMSG) has developed computational models to identify potential sites of high erosion. Two mechanisms were considered to evaluate high erosion locations representative of the actual flow process in the misaligned U2 nozzle, abrasive erosion which occurs by high wall shear of viscous liquid film, and chip-off erosion which is mainly governed by particle impingement. The results show that primary locations of the highest erosion due to particle impingement are at the occurrence of sudden change of flow direction, sudden contraction, and flow obstruction as expected. Potential damage sites due to the abrasive wall erosion are at the upstream and downstream regions of sudden changes of flow direction.
Date: November 19, 2002
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Heat Balance Study for Submersible Mixer Pump

Description: A transient heat balance model was developed to assess the impact of a Submersible Mixer Pump (SMP) on waste temperature during the process of waste mixing and removal for the Type-I SRS tanks. The model results will be mainly used to determine the SMP design impacts on the waste tank temperature during operations and to develop a specification for a new SMP design to replace existing long-shaft mixer pumps used during waste removal. The model will also be used to provide input to the operation planning. This planning will be used as input to pump run duration in order to maintain temperature requirements within the tank during SMP operation.
Date: July 21, 2003
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Heat Transfer Analysis for a Fixed CST Column

Description: In support of a small column ion exchange (SCIX) process for the Savannah River Site waste processing program, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the crystalline silicotitanate (CST) column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. A series of the modeling calculations has been performed using a computational heat transfer approach. Results for the baseline model indicate that transit times to reach 130 degrees Celsius maximum temperature of the CST-salt solution column are about 96 hours when the 20-in CST column with 300 Ci/liter heat generation source and 25 degrees Celsius initial column temperature is cooled by natural convection of external air as a primary heat transfer mechanism. The modeling results for the 28-in column equipped with water jacket systems on the external wall surface of the column and water coolant pipe at the center of the CST column demonstrate that the column loaded with 300 Ci/liter heat source can be maintained non-boiling indefinitely. Sensitivity calculations for several alternate column sizes, heat loads of the packed column, engineered cooling systems, and various ambient conditions at the exterior wall of the column have been performed under the reference conditions of the CST-salt solution to assess the impact of those parameters on the peak temperatures of the packed column for a given transient time. The results indicate that a water-coolant pipe at the center of the CST column filled with salt solution is the most effective one among the potential design parameters related to the thermal energy dissipation of decay heat load. It is noted that the cooling mechanism ...
Date: February 19, 2004
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Heat Transfer Calculations for Normal Operations of a Fixed CST Bed Column

Description: In support of the crystalline silicotitanate (CST) ion exchange project of High-Level Waste (HLW) Process Engineering, heat transfer calculations have been made for a fully-loaded CST column during abnormal and normal operating conditions. The objective of the present work is to compute temperature distributions across the column when there is steady flow of salt solution through the CST column under normal conditions of the process operations.
Date: September 10, 2001
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Heel Removal Analysis for Mixing Pumps of Tank 8

Description: Computational fluid dynamics methods were used to recommend a slurry pump operational strategy for sludge heel removal in Tank 8. Flow patterns calculated by the model were used to evaluate the performance of various combinations of operating pumps and their orientation. The models focused on removal of the sludge heel located at the east side of Tank 8 using the four existing slurry pumps. The models and calculations were based on prototypic tank geometry and expected normal operating conditions as defined by Waste Removal Closure (WRC) Engineering. The calculated results demonstrated that for pump speeds higher than 1800 rpm and at a 130 inch liquid level, a recommended orientation of the slurry pumps could be provided, based on a minimum sludge suspension velocity of 2.27 ft per sec. Further results showed that the time to reach a steady-state flow pattern was affected by both the tank level and the pump speed. Sensitivity studies showed that for a given pump speed, a higher tank level and a lower pump nozzle elevation would result in better performance in suspending and removing the sludge. The results also showed that the presence of flow obstructions were advantageous for certain pump orientations.
Date: May 21, 2003
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Sludge Heel Removal Analysis for Slurry Pumps of Tank 11

Description: Computational fluid dynamics methods were used to develop and recommend a slurry pump operational strategy for sludge heel removal in Tank 11. Flow patterns calculated by the model were used to evaluate the performance of various combinations of operating pumps and their orientation. The models focused on removal of the sludge heel located at the edge of Tank 11 using the four existing slurry pumps. The models and calculations were based on prototypic tank geometry and expected normal operating conditions as defined by Tank Closure Project (TCP) Engineering. Computational fluid dynamics models of Tank 11 with different operating conditions were developed using the FLUENT(tm) code. The modeling results were used to assess the efficiency of sludge suspension and removal operations in the 75-ft tank. The models employed a three-dimensional approach, a two-equation turbulence model, and an approximate representation of flow obstructions. The calculated local velocity was used as a measure of sludge removal and mixing capability. For the simulations, a series of the modeling calculations was performed with indexed pump orientations until an efficient flow pattern near the potential location of the sludge mound was established for sludge removal. The calculated results demonstrated that the existing slurry pumps running at 1600 rpm could remove the sludge mound from the tank with a 103 in. liquid level, based on a minimum sludge suspension velocity of 2.27 ft/sec. In this case, the only exception is the region within about 2 ft. from the tank wall. Further results showed that the capabilities of sludge removal were affected by the indexed pump orientation, the number of operating pumps, and the pump speed. A recommended operational strategy for an efficient flow pattern was developed to remove the sludge mound assuming that local fluid velocity can be used as a measure of sludge suspension and removal. ...
Date: September 30, 2003
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Three-Dimensional CFD FLYGT Mixer Model and Results

Description: The main objectives of the present work are to examine detailed flow performance of the Tank 19 FLYGT mixer improved by the previous work, to conduct sensitivity analysis for a wide range of possible boundary conditions, and to investigate transient flow behavior and loading of the FLYGT mixer. For the present study, a flow simulation method is developed to calculate the flow around a marine-type propeller configuration of the FLYGT mixer.
Date: April 16, 2002
Creator: Lee, S. Y.
Partner: UNT Libraries Government Documents Department

Performance Analysis for Mixing Pumps in Tank 18

Description: In support of sludge suspension and mixing operations in Tank 18, flow evolution models were developed and performance calculations completed for the advanced design mixer pump (ADMP) and the modified ADMP (MADMP). The MADMP was being considered as a replacement for the ADMP in Tank 18. The models and calculations were based on prototypic tank geometry and expected normal operating conditions as defined by Waste Removal Closure (WRC) Engineering. Computational fluid dynamics models of both the TNX full tank experimental facility and Tank 18 were developed using the FLUENT(tm) code. TNX test data were used to benchmark the models and assess the efficiency of sludge suspension and removal operations in the 85 ft tank. The models employed a three-dimensional approach, a two-equation turbulence model, and a stepped-rotation approximation to estimate pump rotation effects. A two-dimensional approach was also used as a scoping analysis to examine multi-dimensional effects of fluid motion on the flow circulation patterns in the tank. The results were verified by both TNX test data and literature data. Local velocity was used as a measure of slurrying and mixing capability. The results showed that normal operations in Tank 18 with the existing ADMP mixer and a 70 inch liquid level provide adequate sludge removal in most regions of the tank. The exception is the region within about 2 ft of the wall, assuming the minimum velocity required to suspend waste sludge is 2.27 ft/sec. Further results showed that the time to reach a steady-state flow pattern was affected by both pump rotation and pump location. Sensitivity studies showed that a higher tank level and the smaller nozzle size would result in better performance in suspending and removing the sludge. The results also showed that the MADMP mixer has the best sludge removal capacity. Computational results for two different ...
Date: April 16, 2002
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Evaluation of Sludge Removal Capabilities for ADMP Mixer in Tank 18

Description: The primary objective of the present work is to model Tank 18 with the existing ADMP mixer for various pump elevations and tank liquid levels when the mixer is submerged at the center of the tank. The computational models will be used to estimate the cleaning capabilities of the ADMP for sludge removal and to evaluate flow evolutions of waste slurry under various operating conditions in Tank 18. The basic CFD model for the Tank 18 system was developed and benchmarked against the TNX test data and literature data in the previous work . The analysis results will be used to evaluate hydraulic cleaning operations for waste removal. This information will also assist in the operating plan for Tank 18 waste removal and in identifying special requirements for sampling and monitoring the sludge suspension.
Date: July 21, 2003
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Investigation of heat transfer and combustion in the advanced fluidized bed combustor (FBC)

Description: This technical report summarizes the research conducted and progress achieved during the period from April 1, 1998 to June 30, 1998. The numerical simulation was continued to determine the concentration distribution of the gas species, heat flux and heat transfer coefficients in the hot combustor model. The different gas concentration profiles showed the gas mixing characteristics along the combustor height. The center zone of the combustor has a relatively high methane mass concentration. The injection of secondary air squeezes the uprising flue gas and methane that causes the fuel-lean zone near the secondary air nozzles. The carbon dioxide concentration increased with the increasing of the combustor height. The peak concentration of oxygen remains at the combustor wall because of the secondary injection. The heat flux on the wall of the upper chamber is much higher than that of the lower chamber. It is believed that the heat flux is affected by the designed strong swirl and secondary air injection. The heat transfer coefficient changes along the combustor height were also affected by the multiple secondary air injection. The numerical simulation results could verify the predictions of the experimental results. It is a quite similar trend of the heat transfer coefficient changes based on the combustion test results.
Date: September 1, 1999
Creator: Lee, S.W.
Partner: UNT Libraries Government Documents Department

Agitator Mixing Analysis in a HB-Line Flat Tank

Description: In support of the HB-Line Engineering agitator mixing project, flow pattern calculations have been made for a 45 degrees pitched three-blade agitator submerged in a flat rectangular tank. The work is intended to determine agitator speeds that provide acceptable mixing performance for various tank liquid levels based on flow rates past solids deposited on the bottom surface of the flat tank. The modeling results will help ensure the acceptable suspension of solid particles as a function of agitator speed and tank liquid level during precipitation operations. The numerical modeling and calculations have been performed using a computational fluid dynamics approach. Three-dimensional steady-state momentum and continuity equations were used as the basic equations to estimate fluid motion driven by an agitator with three 45 degrees pitched blades. Hydraulic conditions were fully turbulent (Reynolds number about 2x104). A standard two-equation turbulence model (k-e), was used to capture turbulent eddy motion. The commercial finite volume code, Fluent [7], was used to create a prototypic geometry file with a non-orthogonal mesh. Hybrid meshing was used to fill the computational region between the round-edged tank bottom and agitator regions. At high rotational speeds and low tank levels, a surface vortex can reach the agitator blades and allow air to be drawn into the solid-fluid mixing zone. This is not desirable in terms of mixing performance. The analysis results show that the lowest liquid level among the four considered, 4.5 inches, is higher than the critical liquid height for air entrainment for agitator speeds up to 600 rpm. All the analysis results demonstrate that about 600 rpm provides adequate solids mixing capability for various tank levels (12, 8.5, 7, and 4.5 inches) containing 20-micron solids with a specific gravity of 2.5.
Date: July 31, 2002
Creator: Lee, S.Y.
Partner: UNT Libraries Government Documents Department

Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion (FBC) system. Technical progress report No. 8, July 1994--September 1994

Description: This technical report summarizes the research work performed and progress achieved during the period of July 1, 1994 to September 30, 1994. The metal wastage of AISI 1018 low carbon steel at different particle velocity was discussed to understand the erosion phenomena of in-bed tube in FBC system. At both low velocity (2.5 m/s) and high (30 m/s), the maximum metal wastage was occurred at 45{degrees} of impact angle. The erosion rates at low particle velocity were two (2) to three (3) orders of magnitude lower than those at high particle velocity. The characteristics of anti-erosion and design considerations were discussed and suggested for some basic design guidelines, which might be important to the designer of bubbling fluidized combustors. The working principle and mechanism of anti-erosion devices will be discussed. Based upon the understanding of the working principle and mechanism of anti-erosion devices, different types of ant-erosion tube will be designed for the cold model bench-scale FBC system.
Date: October 1, 1994
Creator: Lee, S.W.
Partner: UNT Libraries Government Documents Department

Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion (FBC) system. Technical progress report No. 12

Description: This technical report summarizes the research work performed and progress achieved during the period of July 1, 1995 to October 30, 1995. The characteristics of resistant coatings were determined and related to metal wastage of in-bed tubes in FBC under various laboratory test conditions, The tests were conducted at high impact velocity, 30 m/s, and short exposure time (4 hours) to minimize oxidation of surrounding surface specimens. No oxidation layer founded on the worn surfaces of AISI 1018 carbon steel, The eroded surfaces and cross sections of coatings tested at high velocity were investigated, The surfaces of coating specimens were eroded through a combined mechanism of brittle and ductile modes, These mechanical properties of materials are strongly dependent on the composition and microstate of materials, rather than to their hardness, For high velocity testing, all of the coatings exhibited {open_quotes}brittle behavior{close_quotes}, i.e., the erosion rate at shallow angles was higher than at steep angles and maximum erosion rate at impact angle of 90{degrees}. Tests will be continued and compared with erosion test results for different thermal sprayed coatings.
Date: October 1, 1995
Creator: Lee, S.W.
Partner: UNT Libraries Government Documents Department

Investigation of heat transfer and combustion in the advanced fluidized bed combustor (FBC)

Description: This technical report summarizes the research work performed and progress achieved during the period of October 1, 1994 to December 31, 1994. The measurement of gas flow continued with the assumption of axisymmetric flow in the laboratory-scale FBC. The gas axial velocity distributions at two cross-section in the test chamber were presented. The circulating flow is relatively strong (swirl number of 3.0) near the freeboard wall for the two cross-sections because the flow has high reversal air velocity. The recirculation flow had weak air velocity when the swirl number of 0.60. For the non-swirling flow, the axial velocity was low near the freeboard wall. However, no circulating flow was observed at the two cross-sections. The measurement of the gas axial velocity will be continued to observe the effect of the secondary air injection angles.
Date: January 1, 1995
Creator: Lee, S.W.
Partner: UNT Libraries Government Documents Department