Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “GAS REACTOR”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35

Initial Gamma Spectrometry Examination of the AGR-3/4 Irradiation

The initial results from gamma spectrometry examination of the different components from the combined third and fourth US Advanced Gas Reactor Fuel Development TRISO-coated particle fuel irradiation tests (AGR-3/4) have been analyzed. This experiment was designed to provide information about in-pile fission product migration. In each of the 12 capsules, a single stack of four compacts with designed-to-fail particles surrounded by two graphitic diffusion rings (inner and outer) and a graphite sink were irradiated in the Idaho National Laboratory’s Advanced Test Reactor. Gamma spectrometry has been used to evaluate the gamma-emitting fission product inventory of compacts from the irradiation and evaluate the burnup of these compacts based on the activity of the radioactive cesium isotopes (Cs-134 and Cs-137) in the compacts. Burnup from gamma spectrometry compares well with predicted burnup from simulations. Additionally, inner and outer rings were also examined by gamma spectrometry both to evaluate the fission product inventory and the distribution of gamma-emitting fission products within the rings using gamma emission computed tomography. The cesium inventory of the scanned rings compares acceptably well with the expected inventory from fission product transport modeling. The inventory of the graphite fission product sinks is also being evaluated by gamma spectrometry.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Support for Fuel Fabrication and Characterization

Oak Ridge National Laboratory (ORNL) has participated in the Advanced Gas Reactor (AGR) program for the Next Generation Nuclear Plant (NGNP) and the transition to the Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) Technology Development Office (TDO) since the inception of the program. In this effort, ORNL has fabricated tristructural isotropic (TRISO) fuel and fuel compacts for AGR-1, AGR-2, and AGR-3/4 experiments, provided matrix only components for AGC-2, AGC-4, and AGR 3/4 experiments and for university studies, and provided characterization, coating, and compaction support for INL and BWX Technologies Nuclear Operations Group (BWXT). In fiscal year (FY) 2017, the activities for the INL ART TDO fuel development are focused on preparations for the AGR-5/6/7 experiments and technical support to the Generation-IV International Forum (GIF) pre-irradiation leach-burn-leach (LBL) round robin effort with China and South Korea. With the successful transfer of fuel fabrication technology to BWXT, ORNL’s involvement has shifted toward transferring fuel characterization methods, providing technical support, verification of BWXT laboratory results, and fabricating surrogate fuel materials for university collaborations. ORNL will also provide analytical support to BWXT and INL for uranium dispersion analysis and confirmatory fuel characterization analyses as needed.

Grain Boundary Characteristics of SiC in Irradiated, AGR-2 TRISO Particles

Microstructural characterization of the SiC layer was carried out on neutron irradiated, tristructural isotropic (TRISO) particles from the Advanced Gas Reactor (AGR)-2 experiment. The SiC grain boundary distribution in each particle was characterized with precession electron diffraction in the transmission electron microscope. Generally, the distributions in the AGR-2 TRISO particles (fabricated at the pilot scale by an industrial vendor) were similar to the Variant 3, AGR-1 TRISO particles made on a laboratory-scale at Oak Ridge National Laboratory. Slightly more random, high-angle grain boundaries in conjunction with slightly less low-angle grain boundaries were found in the AGR-2 TRISO particles compared to AGR-1 TRISO particles. Plotting the Ag-110m retention exhibited by both Variant 3 AGR-1 and AGR-2 irradiated TRISO particles against various grain boundary types revealed Ag retention correlate with the random, high-angle and twin grain boundary fraction in the center area of the SiC layer. Observations associated with localized areas of precipitation also will be reported in this paper.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Irradiated AGR-2 Compact 3-1-1 Examination Plan

This plan describes post-irradiation examination (PIE) activities (safety testing and post-safety test analyses) to be performed by Oak Ridge National Laboratory (ORNL) on irradiated Compact 3-1-1 taken from the Advanced Gas Reactor (AGR) experiment, AGR 2. This work will be performed in accordance with general objectives outlined in the AGR-2 PIE plan and guidance in the ORNL PIE statement of work.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Validation of RELAP5-3D He-FUS3 Data

The RELAP5-3D computer code was validated using data from the HE FUS3 experimental facility. HE FUS3 is a helium-cooled, electrically-heated experimental facility that was used to generate experimental data for a benchmark exercise aimed at the validation of system transient analysis codes for very-high-temperature gas reactor applications. RELAP5-3D was validated using results from seven steady-state tests and one transient that simulated a loss-of-flow accident.

97 MATHEMATICS AND COMPUTING↗

Irradiated AGR 2 Compact 4-1-2 Examination Plan

This plan describes post-irradiation examination (PIE) activities (safety testing and post-safety test analyses) to be performed by Oak Ridge National Laboratory (ORNL) on irradiated Compact 4-1-2 taken from the Advanced Gas Reactor (AGR) experiment, AGR 2. This work will be performed in accordance with the Statement of Work for PIE and Safety Testing of Pebble Bed Modular Reactor Limited (PBMR) Fuel at ORNL.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Support for Fuel Fabrication and Characterization

Oak Ridge National Laboratory (ORNL) has participated in the Advanced Gas Reactor (AGR) program for the Next Generation Nuclear Plant (NGNP) and the transition to the Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) Technology Development Office (TDO) since the inception of the program. In this effort, ORNL has fabricated tristructural isotropic (TRISO) fuel and fuel compacts for AGR-1, AGR-2, and AGR-3/4 experiments, provided matrix only components for AGC-2, AGC-4, and AGR 3/4 experiments and for university studies, and provided characterization, coating, and compaction support for INL and BWX Technologies Nuclear Operations Group (BWXT). In fiscal year (FY) 2017, the activities for the INL ART TDO fuel development are focused on preparations for the AGR-5/6/7 experiments and technical support to the Generation IV (GenIV) pre-irradiation leach-burn-leach round robin effort with China and South Korea. With the successful transfer of fuel fabrication technology to BWXT, ORNL’s involvement has shifted toward transferring fuel characterization methods, providing technical support, verification of BWXT laboratory results, and fabricating surrogate fuel materials for university collaborations. ORNL will also provide analytical support to BWXT and INL for uranium dispersion analysis and confirmatory fuel characterization analyses as needed.

Support for Fuel Fabrication and Characterization

Oak Ridge National Laboratory (ORNL) has participated in the Advanced Gas Reactor (AGR) program for the Next Generation Nuclear Plant (NGNP) and the transition to the Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) Technology Development Office (TDO) since the inception of the program. In this effort, ORNL has fabricated tristructural isotropic (TRISO) fuel and fuel compacts for AGR-1, AGR-2, and AGR-3/4 experiments, provided matrix only components for AGC-2, AGC-4, and AGR 3/4 experiments and for university studies, and provided characterization, coating, and compaction support for INL and BWX Technologies Nuclear Operations Group (BWXT). In fiscal year (FY) 2018, the activities for the INL ART TDO fuel development are focused on final characterization to support the AGR-5/6/7 experiments and technical support to the Generation-IV International Forum (GIF) pre-irradiation leach-burn-leach (LBL) round robin effort with China and South Korea.

Disposition Plan for AGR-Related Equipment and Materials

The Advanced Gas Reactor (AGR) program has purchased equipment, chemicals, and acquired uranium feedstocks for the purpose of developing fuel fabrication processes, fabricating fuel for irradiation experiments, and growing domestic expertise. During the process of fuel development and qualification activities, various quantities of unused chemicals, uranium feedstocks, intermediate materials, scrap, and waste have accumulated at BWX Technologies Nuclear Operations Group (BWXT-NOG) and Oak Ridge National Laboratory (ORNL) that must be properly dispositioned. More expensive standalone equipment will be shipped to and repurposed at the Idaho National Laboratory(INL) and ORNL. Less expensive standalone equipment will be either abandoned in place for use by BWXT-NOG or discarded. Embedded equipment, that effects the functionality of BWXT-NOG systems, will be either abandoned in place or dismantled for disposal. Residual chemicals and non-fuel materials used for fuel fabrication and characterization will be repurposed when economically viable or discarded. High-purity uranium oxides, crystals, and metal will be repurposed for fuel fabrication. The majority of the high-enriched uranium will be included in an upcoming Central Scrap Management Office down blending operation. Archival materials will be collected of low-enriched uranium fuel kernels, tristructural isotropic (TRISO) fuel particles, and fuel compact that are residues of AGR fuel fabrication activities. Archival materials will be stored at either INL or ORNL. Some quality, unenriched uranium materials, that may be of interest to other parties investigating TRISO fuels, will also be archived. Uranium materials that are not archived and which cannot be readily repurposed will be discarded.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Test Plan for the 1600°C Heating Test of AGR-3/4 Compact 3-2

Post irradiation examination (PIE) and heating tests of tristructural isotropic (TRISO)-coated fuel particles, fuel compacts, and graphite from the Advanced Gas Reactor (AGR) irradiation experiment AGR 3/4 is in progress. The AGR-3/4 test train consisted of twelve separate capsules irradiated in the northeast flux trap of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) from December 14, 2011, to April 12, 2014 (Collin 2015). This test plan describes the heating test of AGR-3/4 Compact 3-2. The heating test will involve heating the compact in the Fuel Accident Condition Simulator (FACS) furnace to a peak temperature of 1600°C while collecting fission products released from the compact for subsequent analysis. One of several features of AGR-3/4 that set it apart from AGR-1 and AGR-2 is the incorporation of 20 designed-to-fail (DTF) particles in each compact. The fuel kernels in the DTF particles were coated only with a thin (20 µm thick) pyrocarbon layer having high anisotropy such that the coating should most-likely fail during the irradiation, resulting in up to 20 exposed kernels per compact. One of the main goals of this test is to assess the retention of fission products in the exposed kernels and the surrounding graphitic matrix material comprising the compact. Future heating tests will expose AGR-3/4 compacts at different temperatures in the FACS furnace (Demkowicz 2017). Additionally, the ability may be developed to heat re-irradiated AGR-3/4 compacts to allow a determination of the retention of short-lived fission products I-131 and Xe-133.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Test Plan for the Second Reirradiation Heating Test of Fuel Particles from AGR 2 Compact 6-4-1

Post irradiation examination (PIE) and high-temperature heating tests of tristructural isotropic (TRISO)-coated fuel particles and compacts from the second Advanced Gas Reactor (AGR) irradiation experiment, AGR 2, are in progress. This test plan describes the reirradiation and subsequent high-temperature testing of loose fuel particles obtained from AGR 2 compact 6-4-1. Four of these particles will have been cracked, gamma counted, and re-irradiated in the Neutron Radiography (NRAD) reactor prior to the heating test. The heating test will involve heating the particles in the Fuel Accident Condition Simulator (FACS) furnace to a peak temperature of approximately 1600°C while collecting fission products released from the particles for post-heating test analysis. The intention of the test is to assess the retention of fission products in the fuel kernel. Reirradiation of the particles will allow a determination of the retention of short-lived fission products I-131 (t1/2 = 8.02 days) and Xe-133 (t1/2 = 5.2 days) in the kernel.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Test Plan for the 1400°C Heating Test of AGR-3/4 Compact 10-4

Post irradiation examination (PIE) and heating tests of tristructural isotropic (TRISO)-coated fuel particles, fuel compacts, and graphite from Advanced Gas Reactor (AGR) irradiation experiment AGR 3/4 is in progress. The AGR-3/4 test train consisted of twelve separate capsules irradiated in the northeast flux trap of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) from December 14, 2011, to April 12, 2014 (Collin 2015). This test plan describes the heating test of AGR-3/4 Compact 10-4. The test will involve heating the compact in the Fuel Accident Condition Simulator (FACS) furnace to a peak temperature of 1400°C while collecting fission products released from the compact for subsequent analysis. One of several features of AGR-3/4 that set it apart from AGR-1 and AGR-2 is the incorporation of 20 designed-to-fail (DTF) particles in each compact. The fuel kernels in the DTF particles were coated only with a thin (20 µm thick) pyrocarbon layer having high anisotropy such that the coating would most-likely fail during the irradiation, resulting in up to 20 exposed kernels per compact. One of the main goals of this test is to assess the retention of fission products in the exposed kernels and the surrounding graphitic matrix material comprising the compact. Future heating tests will expose a number of AGR-3/4 compacts at different temperatures in the FACS furnace (Demkowicz 2017). Additionally, the ability may be developed to heat re-irradiated AGR-3/4 compacts to allow a determination of the retention of short-lived fission products I-131 and Xe-133.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Instrumentation Plan for the OSU High Temperature Test Facility, Revision 4

This instrumentation plan describes the instrumentation requirements and design for the Oregon State University (OSU) High Temperature Test Facility (HTTF). This report outlines HTTF instrumentation design specifications, data acquisition and control system (DACS) design specifications as well as a brief description of the instrumentation to be used in the HTTF. The HTTF is an integral test facility, which has been designed to model the behavior of interest for a Very High Temperature Gas Reactor (VHTR) during the Depressurized Conduction Cooldown (DCC) event. It also has the potential to conduct limited explorations into the progression of the Pressurized Conduction Cooldown (PCC) event and phenomena during normal operations. The facility is scaled 1:4 by height and 1:64 by volume. The maximum core power for the facility is approximately 2.2MW. The core region is of a modular design to allow for both the prismatic block core and the pebble bed core designs to be tested. However, only the prismatic block design is discussed in this report. A correctly scaled integral facility modeling the VHTR that can be used to examine the thermal hydraulic system behavior of the design basis and beyond design basis transients is of significant value. The experimental results obtained in such a program could be used to validate analytical tools and methods being proposed for use with the VHTR. Therefore, it is of importance that the HTTF be instrumented in such a way that the required data is collected to meet its overall goals of phenomena examination and code validation. In addition to the instrumentation used to collect data to achieve the overall goals of the HTTF test program, there is instrumentation in the HTTF, which is primarily used to ensure the safe operation of the test facility. This type of instrumentation shall be termed “Control Instrumentation” and is discussed in this report. This report discusses the DACS, which is a personal computer controlled system that is used to control both the collection and storage of the test matrix and control system data as well as electrical and mechanical operation of the test facility.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Test Plan for the Reirradiation Heating Test of Fuel Particles from AGR 2 Compact 5-4-2

Post irradiation examination (PIE) and high-temperature heating tests of tristructural isotropic (TRISO)-coated fuel particles and compacts from the second Advanced Gas Reactor (AGR) irradiation experiment, AGR 2, are in progress. This test plan describes the reirradiation and subsequent high-temperature testing of loose fuel particles obtained from AGR 2 Compact 5-4-2. To simulate exposed kernels, four of these particles have been cracked at Oak Ridge National Laboratory (ORNL) to produce localized defects that extend through the TRISO layers (outer-pyrolytic carbon [OPyC], silicon carbide [SiC], and inner-pyrolytic carbon [IPyC]) while keeping these layers in-place and maintaining the shape and integrity of the kernel. To generate short-lived fission products, these particles will be reirradiated in the Neutron Radiography (NRAD) reactor prior to heating testing in the Fuel Accident Condition Simulator (FACS) furnace. FACS testing will be at 1600°C, and fission products released from the reirradiated particles will be measured. The intention of the test is to assess the retention of short-lived fission products I-131 (t1/2 = 8.02 days) and Xe-133 (t1/2 = 5.2 days) in the fuel kernels at accident temperatures.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Irradiated AGR-2 Compact 6-4-3 Examination Plan

This plan describes post-irradiation examination (PIE) activities (safety testing and post-safety test analyses) to be performed by Oak Ridge National Laboratory (ORNL) on irradiated Compact 6-4-3 taken from the Advanced Gas Reactor (AGR) experiment, AGR 2. This work will be performed in accordance with general objectives outlined in the AGR-2 PIE plan0F and guidance in the ORNL PIE statement of work.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Test Plan for the 1400°C Heating Test of AGR-3/4 Compact 8-2

Post irradiation examination (PIE) and heating tests of tristructural isotropic (TRISO)-coated fuel particles, fuel compacts, and graphite from Advanced Gas Reactor (AGR) irradiation experiment AGR 3/4 is in progress. The AGR-3/4 test train consisted of twelve separate capsules irradiated in the northeast flux trap of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) from December 14, 2011, to April 12, 2014 (Collin 2015). This test plan describes the heating test of AGR-3/4 Compact 8-2. The test will involve heating the compact in the Fuel Accident Condition Simulator (FACS) furnace to a peak temperature of 1400°C while collecting fission products released from the compact for subsequent analysis. One of several features of AGR-3/4 that set it apart from AGR-1 and AGR-2 is the incorporation of 20 designed-to-fail (DTF) particles in each compact. The fuel kernels in the DTF particles were coated only with a thin (20 µm thick) pyrocarbon layer having high anisotropy such that the coating would most-likely fail during the irradiation, resulting in up to 20 exposed kernels per compact. One of the main goals of this test is to assess the retention of fission products in the exposed kernels and the surrounding graphitic matrix material comprising the compact. Future heating tests will expose a number of AGR-3/4 compacts at different temperatures in the FACS furnace (Demkowicz 2017). Additionally, the ability may be developed to heat re-irradiated AGR-3/4 compacts to allow a determination of the retention of short-lived fission products I-131 and Xe-133.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Test Plan for the 1200°C Heating Test of AGR-3/4 Compact 10-2

Post irradiation examination (PIE) and heating tests of tristructural isotropic (TRISO)-coated fuel particles, fuel compacts, and graphite from Advanced Gas Reactor (AGR) irradiation experiment AGR 3/4 is in progress. The AGR-3/4 test train consisted of twelve separate capsules irradiated in the northeast flux trap of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) from December 14, 2011, to April 12, 2014 (Collin 2015). This test plan describes the heating test of AGR-3/4 Compact 10-2. The test will involve heating the compact in the Fuel Accident Condition Simulator (FACS) furnace to a peak temperature of 1200°C while collecting fission products released from the compact for subsequent analysis. One of several features of AGR-3/4 that set it apart from AGR-1 and AGR-2 is the incorporation of 20 designed-to-fail (DTF) particles in each compact. The fuel kernels in the DTF particles were coated only with a thin (20 µm thick) pyrocarbon layer having high anisotropy such that the coating would most-likely fail during the irradiation, resulting in up to 20 exposed kernels per compact. One of the main goals of this test is to assess the retention of fission products in the exposed kernels and the surrounding graphitic matrix material comprising the compact. Future heating tests will expose a number of AGR-3/4 compacts at different temperatures in the FACS furnace (Demkowicz 2017). Additionally, the ability may be developed to heat re-irradiated AGR-3/4 compacts to allow a determination of the retention of short-lived fission products I-131 and Xe-133.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

AGR-3/4 Compact 1-4 Examination Plan

This plan describes the post irradiation examination (PIE) activities to be performed by Oak Ridge National Laboratory (ORNL) on irradiated Compact 1-4 taken from the Advanced Gas Reactor (AGR) experiment, AGR-3/4. This work will be performed in accordance with the general objectives outlined in the AGR 3/4 PIE Plan and guidance in the ORNL PIE Statement of Work.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗