Development, Verification, and Validation of an Advanced Systems Code KP-SAM for Kairos Power Fluoride Salt–Cooled High-Temperature Reactor (KP-FHR)
Not provided.
Nuclear Science & Technology↗
SEARCH · Engineering Papers
Results for “KP”
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.
Correlation of Kp with the substorm-injected plasma boundary
The local time position of the low-energy substorm-injected plasma boundary in the dusk to midnight region of the magnetosphere as observed by the geostationary satellite ATS 5 is found to be correlated with the interpolated Kp index. Considering the time resolution of Kp, the correlation is found to be quite close but dependent on season. An estimate of the overall shape and position of the low-energy boundary within this region of the magnetosphere as a function of Kp is found by using a fit to the authors' winter data correlation in conjunction with a fit of data presented by Carpenter (1967) concerning the Kp-related radial positioning of the plasmapause boundary in the postmidnight region. This analysis results in a spiral structure, the scale of which depends on Kp.
Mauk, B. H.↗
Modeling and Simulation Development Pathways to Accelerating KP-FHR Licensing (Final Report)
This project assembles a strong U.S. industry and national laboratory team to complete scope of work. Kairos Power (KP), headquartered in Alameda, CA, is the leader of this effort and has built an internal team of highly competent engineers and managers with extensive combined experience in nuclear power, conventional power, product development, and licensing. INL, ANL, and LANL bring unique capabilities in advanced reactor R&D and licensing. The project funding source is the result of FOA No. 0001817, U. S. Industry Opportunities for Advanced Nuclear Technology Development. There has been on-going work and this Access Cooperative Research and Development Agreement (CRADA) will cover the remaining work scope of FOA 0001817. KP is implementing innovative strategies that can reduce the cost and accelerate the initial demonstration of the Kairos Power Fluoride-salt-cooled, High-temperature Reactor (KP-FHR) to meet the needs of the U.S. electricity market by 2030. Licensing of the KP-FHR could be significantly accelerated using advanced computing methods with sufficient predictive capabilities to be able to extrapolate potential response of the structure in different scenarios. However, currently used computational methods heavily rely on empirical fits and cannot be used for extrapolation. The scope focuses on improving the modeling capability in the NEAMS Grizzly structural mechanics code and the NEAMS BISON fuel performance code and the NEAMS SAM systems analysis code. This work leverages the expertise and know-how gathered in three DOE National Laboratories – INL, ANL, and LANL.
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
High Fidelity CFD Simulations Supporting the KP-FHR
Kairos Power, LLC, is developing its version of the Fluoride-cooled High-temperature Reactor, the KP-FHR. The design uses a pebble bed core with fluoride salt as a coolant. The pebbles used in the KP-FHR have a diameter of 4 cm, with a shell fuel region where TRISO particles are embedded. A Pebble bed core design is adopted by several Gen IV reactors, They boast many benefits, such as fuel integrity, highly efficient heat transfer, and passive safety. However, it is challenging to accurately predict temperature and flow inside a pebble bed. Traditional approaches use the porous media model, which regards the pebble bed as a continuous medium, but with different temperature fields representing different levels, such as the fluid temperature, pebble surface temperature, and pebble center temperature. Empirical heat transfer correlations are adopted to calculate the heat transfer coefficient between different phases. However, empirical correlations are usually validated with experimental data, which usually lacks detail inside the pebble bed. The available experimental data is also generally at a high Reynolds number, which falls outside of the conditions of KP-FHR. Explicit computational fluid dynamics (CFD) simulations of randomly packed pebble beds have only become feasible recently. This is thanks to the rapid development of computational power and scalable algorithms. In this work, we used the Spectral Element Method (SEM) CFD code NekRS to simulate the randomly packed pebble bed in a cylindrical container. NekRS, which is the GPU variant of Nek5000, but refactored to utilize the computational power of GPUs using the OCCA library to run on hybrid architecture high performance computing systems. It was initially developed with the libParamunal library, but truncated and tuned for large-scale turbulence simulation. As a result, the SEM reaches higher precision with the same degrees of freedom by using a high-order Lagrange polynomial basis distributed on Gauss-Lobatto-Legendre quadrature inside each element, compared to lower-order methods, such the Finite Volume Method and Finite Element Method. The report is divided into five parts. We start with a general discussion of the pebble bed reactor, along with a specific investigation into the KP-FHR. The second part presents the numerical methodology. In the third part, we study a modular pebble bed with 1741 pebbles in a container of 7 pebble-diameter radius. Beyond LES simulations done by NekRS, we also leveraged the thermal radiation model in OpenFOAM to study heat transfer under no-forced-flow scenarios. Then, in the fourth part we simulated a pebble bed similar to the size of the Hermes Test Reactor. The total number of pebbles is in these simulations is 34,374. The container radius is 14 pebble-diameters. Finally, the report concludes in part five, with a discussion of future work.
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
Kp dependence of the plasma sheet boundary
An empirical relationship has been obtained between the location of the inner boundary of the plasma sheet along the geostationary orbit and Kp. Through the use of an analytical expression for the shape of the boundary and a relationship between the convection electric field and Kp this result is extended to yield the radial position of the boundary versus Kp. The result illustrates the high degree of sensitivity of measurements in the geostationary orbit region to shifts in the plasma sheet position arising from geomagnetic activity or an increasing convection electric field.
Freeman, J. W.↗
The plasma sheet boundary and Kp
The paper studies data obtained by the suprathermal ion detector aboard the ATS-1 geostationary satellite in order to establish a relation between the local time occurrence of the plasma sheet at the geostationary orbit (6.6 earth radii) and the Kp index. This relation is then used along with Alfven and Falthammer's (1963) equation for the drift path of an electron moving under the combined influence of a homogeneous electric field and a dipole magnetic field to derive an expression that shows the manner in which the inner boundary of the plasma sheet can be expected to vary radially with Kp along the midnight meridian for Kp less than about 4.
Freeman, J. W.↗
Materials Data on KP(OF)2 by Materials Project
KP(OF)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to six equivalent O2- and two F1- atoms. There are a spread of K–O bond distances ranging from 2.78–3.13 Å. There are one shorter (2.87 Å) and one longer (3.18 Å) K–F bond lengths. P5+ is bonded in a tetrahedral geometry to two equivalent O2- and two F1- atoms. Both P–O bond lengths are 1.49 Å. Both P–F bond lengths are 1.60 Å. O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one K1+ and one P5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one K1+ and one P5+ atom.
36 MATERIALS SCIENCE↗
Comment on 'Kp dependence on sectors, by I. B. McDiarmid and E. E. Budzinski
A suggestion by McDiarmid and Budzinski that an annual variation of geomagnetic activity can explain a sector polarity asymmetry is shown not to be necessary. The correct explanation is that the Kp-index exhibits systematic errors that enhance the UT variation during Toward polarity and decrease the UT variation during Away polarity.
Svalgaard, L.↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.88–3.03 Å. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.53 Å) and two longer (1.60 Å) P–O bond length. H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.05 Å) and one longer (1.48 Å) H–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to two equivalent K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.36 Å. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.21 Å. In the second H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.06 Å) and one longer (1.45 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.20 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 2-coordinate geometry to one H1+ and nine O2- atoms. The K–H bond length is 2.93 Å. There are a spread of K–O bond distances ranging from 2.70–3.34 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.76–3.06 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. There are five inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.55 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a linear geometry to one K1+ and two O2- atoms. There is one shorter (1.05 Å) and one longer (1.46 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.05 Å) and one longer (1.47 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.21 Å. In the fifth H1+ site, H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.21 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one P5+, and one H1+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to one K1+, one P5+, and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one P5+, and one H1+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.75–2.91 Å. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.51–1.65 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one P5+ and one H1+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one P5+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO)2 by Materials Project
KH2PO2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. There are a spread of K–O bond distances ranging from 2.78–2.96 Å. P5+ is bonded in a distorted tetrahedral geometry to two equivalent H1- and two equivalent O2- atoms. Both P–H bond lengths are 1.43 Å. Both P–O bond lengths are 1.52 Å. H1- is bonded in a single-bond geometry to one P5+ atom. O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one P5+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to two equivalent H1+ and six O2- atoms. There are one shorter (2.84 Å) and one longer (2.86 Å) K–H bond lengths. There are a spread of K–O bond distances ranging from 2.71–2.91 Å. P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to two equivalent K1+ and one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent P5+ atoms. In the fourth O2- site, O2- is bonded in a water-like geometry to two equivalent K1+ and two H1+ atoms.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are four shorter (2.91 Å) and four longer (2.92 Å) K–O bond lengths. P5+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All P–O bond lengths are 1.56 Å. H1+ is bonded in a linear geometry to two equivalent O2- atoms. Both H–O bond lengths are 1.21 Å. O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one P5+, and one H1+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP(HO2)2 by Materials Project
KH2PO4 crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 2-coordinate geometry to two equivalent H1+ and six O2- atoms. Both K–H bond lengths are 2.97 Å. There are a spread of K–O bond distances ranging from 2.65–3.05 Å. In the second K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 pentagonal pyramids that share corners with four equivalent PO4 tetrahedra and an edgeedge with one PO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.83–2.91 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent KO6 pentagonal pyramids. There is two shorter (1.51 Å) and two longer (1.61 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share an edgeedge with one KO6 pentagonal pyramid. There is two shorter (1.50 Å) and two longer (1.65 Å) P–O bond length. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.01 Å. In the second H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.03 Å) and one longer (1.54 Å) H–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one P5+, and one H1+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one P5+, and one H1+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one P5+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two K1+ and one P5+ atom.
36 MATERIALS SCIENCE↗
Materials Data on KP by Materials Project
PK1 is Magnesium tetraboride-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six P1- atoms. There are a spread of K–P bond distances ranging from 3.24–3.67 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five P1- atoms. There are a spread of K–P bond distances ranging from 3.20–3.34 Å. There are two inequivalent P1- sites. In the first P1- site, P1- is bonded in a 7-coordinate geometry to five K1+ and two equivalent P1- atoms. There are one shorter (2.26 Å) and one longer (2.28 Å) P–P bond lengths. In the second P1- site, P1- is bonded in a 8-coordinate geometry to six K1+ and two equivalent P1- atoms.
36 MATERIALS SCIENCE↗
Knowledge Graph of RB-Tnseq Data from Fitness Browser (KP-DP1)
Motivation: Predicting microbial gene fitness across environmental conditions remains a central challenge for predictive phenomics and autonomous experimentation. Fitness assays generate large volumes of genotype–phenotype measurements difficult to integrate with experimental metadata and biological function in a form that supports mechanistic reasoning. Knowledge graphs offer a semantic framework for unifying modalities and enabling context-aware inference. Results: We build GIMME (Graph Inference for Microbial Metabolism Exploration), a semantically grounded knowledge graph that unifies gene fitness measurements spanning 10 Pseudomonas species with experimental metadata and biological context. Media are decomposed into chemical components and experiments carry structured links to natural-language descriptions. The resulting graph supports two inference modes: (1) symbolic graph traversal to surface candidate gene–environment and gene–chemical associations, and (2) learned inference using heterogeneous graph neural networks that propagate information across neighborhoods. We formulate link regression over (gene, media, experiment) triplets, combining learned gene embeddings with pretrained LLM sourced text embeddings of node descriptions to predict gene fitness. We then augment a baseline MLP with an auxiliary message-passing encoder (GraphSAGE/GAT) that propagates information over gene–protein–function and media–chemical subgraphs, and fuse the two pathways with a gated residual connection. This approach produces strong agreement with held-out fitness measurements (GraphSAGE Pearson r 0.74) while also highlighting inference challenges in extreme-fitness regimes. We aggregate GAT edge-attention weights by relation type and layer to estimate which biological and environmental relations most influence fitness predictions. Conclusion: This work explores using knowledge graphs as “context graphs” for microbial phenotype prediction. They provide a rich substrate which enables explainable retrieval of supporting evidence, and provides a natural bridge to autonomous workflows that prioritize the next experiment.
59 BASIC BIOLOGICAL SCIENCES↗