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DOE OSTI2023

Emerging Technologies Review: Water Microgrid

Project 69643 Task 10 - The Air Force Civil Engineer Center has tasked Pacific Northwest National Laboratory with investigating emerging technologies to inform the Air Force’s understanding of the technology and to guide key considerations for implementing technologies that are resilient and alternative sources to the traditional methods used in the Air Force today. This report explores the concept of a water microgrid for deployment at Air Force installations. A water microgrid is a local water system that supplies, treats, and distributes water, with the primary objective to meet mission critical water demand during a disruption of the primary supply. A water microgrid can advance an Air Force installation’s water infrastructure and water resilience by being at the ready for meeting critical missions during a utility outage.

42 ENGINEERING↗

DOE OSTI2024

Emerging Technologies Review: Carbon Capture and Conversion to Methane and Methanol

09 BIOMASS FUELS↗

DOE OSTI2023

Emerging Technologies Review: Pumped Storage Hydropower

The Air Force Civil Engineer Center (AFCEC) has tasked Pacific Northwest National Laboratory with investigating emerging technologies to inform the Air Force’s understanding of the technology and to guide key considerations for implementing technologies that are resilient and alternative sources to the traditional methods used in the Air Force today. This report explores pumped storage hydropower. Pumped storage hydropower (PSH) currently provides 93% of grid-scale storage capacity (MW) and 99% of electrical energy storage (MWh) in the United States. PSH exploits the potential energy that can be stored by pumping water to higher elevations or pressures to be dispatched when needed. In its simplest form, PSH uses energy to pump water to an upper reservoir for storage, then releases this water through a turbine and generator into a lower reservoir when needed for energy generation. This report provides a thorough technology description, technical considerations, siting considerations, economic/funding considerations associated with the technology. A Regulatory overview and risks associated with the technology are also included in the report.

13 HYDRO ENERGY↗

DOE OSTI2024

Emerging Technologies Review: Hydrogen Production and Storage

The Air Force Civil Engineer Center has tasked Pacific Northwest National Laboratory with investigating emerging technologies to inform the Air Force’s understanding of the technology and to guide key considerations for implementing technologies that are resilient and alternative sources to the traditional methods used in the Air Force today. This report explores the concept of hydrogen production and storage at Air Force installations.

08 HYDROGEN↗

DOE OSTI2025

Extending quantum-mechanical benchmark accuracy to biological ligand-pocket interactions

Predicting the binding affinity of ligands to protein pockets is key in the drug design pipeline. The flexibility of ligand-pocket motifs arises from a range of attractive and repulsive electronic interactions during binding. Accurately accounting for all interactions requires robust quantum-mechanical (QM) benchmarks, which are scarce for ligand-pocket systems. Additionally, disagreement between “gold standard” Coupled Cluster (CC) and Quantum Monte Carlo (QMC) methods casts doubt on many benchmarks for larger non-covalent systems. We introduce the “QUantum Interacting Dimer” (QUID) benchmark framework containing 170 non-covalent (non-)equilibrium systems modeling chemically and structurally diverse ligand-pocket motifs. Symmetry-adapted perturbation theory shows that QUID broadly covers non-covalent binding motifs and energetic contributions. Robust binding energies are obtained using complementary CC and QMC methods, achieving agreement of 0.5 kcal/mol. The benchmark data analysis reveals that several dispersion-inclusive density functional approximations provide accurate energy predictions, though their atomic van der Waals forces differ in magnitude and orientation. Contrarily, semiempirical methods and empirical force fields require improvements in capturing non-covalent interactions (NCIs) for out-of-equilibrium geometries. The wide span of NCIs, highly accurate interaction energies, and analysis of molecular properties take QUID beyond the “gold standard” for QM benchmarks of ligand-protein systems.

Puleva, Mirela [University of Luxembourg, Luxembou↗

DOE OSTI2024

Maximum Entropy Theory of Multiscale Coarse-Graining via Matching Thermodynamic Forces: Application to a Molecular Crystal (TATB)

The MSCG/FM (multiscale coarse-graining via force-matching) approach is an efficient supervised machine learning method to develop microscopically informed coarse-grained (CG) models. Here we present a theory based on the principle of maximum entropy (PME) enveloping the existing MSCG/FM approaches. This theory views the MSCG/FM method as a special case of matching the thermodynamic forces from the extended ensemble described by the set of thermodynamic (relevant) system coordinates. This set may include CG coordinates, the stress tensor, applied external fields, and so forth, and may be characterized by nonequilibrium conditions. Following the presentation of the theory, we discuss the consistent matching of both bonded and nonbonded interactions. The proposed PME formulation is used as a starting point to extend the MSCG/FM method to the constant strain ensemble, which together with the explicit matching of the bonded forces is better suited for coarse-graining anisotropic media at a submolecular resolution. The theory is demonstrated by performing the fine coarse-graining of crystalline 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), a well-known insensitive molecular energetic material, which exhibits highly anisotropic mechanical properties.

1,3,5-triamino-2,4,6-trinitrobenzene↗

DOE OSTI2024

Forced Oscillation Source Location in Power Systems Using MVMD-assisted DEF in TF Plane

Fast and accurate forced oscillation source location (FOSL) is critical for mitigating forced oscillations in power systems. Here, to overcome the shortcomings of traditional dissipating energy flow (DEF) in decomposing the forced oscillation components from the measurement responses, a multivariate variational mode decomposition (MVMD)-assisted FOSL is proposed in this paper to locate the forced oscillation sources from measurements in time-frequency (TF) plane. The multi-channel measurement matrix of each generator is formed, then the multi-channel modes are decomposed from the formed multi-channel measurement matrix using the MVMD. Further, the intrinsic mode functions (IMFs) associated with the forced oscillation mode are distinguished from the decomposed modes according to the relative energy weights. With the distinguished IMFs, the MVMD-assisted DEF calculation method is developed to locate the forced oscillation source. Finally, the performance of the proposed method is evaluated using the simulation data of the WECC 179-bus test system and IEEE-NASPI Oscillation Source Location Contest as well as the actual PMU data of ISO New England. The results validated the effectiveness and accuracy of the proposed method in the FOSL.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2018

Accessing crystal–crystal interaction forces with oriented nanocrystal atomic force microscopy probes

Biominerals serve as crucial structures of living systems and play an important role for biochemical processes. Understanding their crystallization mechanisms is therefore central to many areas of biology, biogeoscience and biochemistry. Some biominerals, such as bone and dentin, are hierarchical nanocomposite structures constructed by sequentially added individual oriented nanocrystals. The driving forces that enable this oriented assembly are still poorly understood, with advances in understanding limited in part by the availability of techniques that can precisely measure the delicate interactions between nanocrystals, as a function of their separation distance and mutual orientation. Here we provide a novel and comprehensive protocol for i.) fabricating oriented single nanocrystal atomic force microscopy (AFM) probes using focus ion beam (FIB) milling - probes that are capable of accessing the nanoscale forces between oriented single-crystal faces, and ii.) performing oriented nanocrystal interaction force measurements using dynamic force spectroscopy (DFS) and environmental transmission electron microscopy (ETEM)-AFM techniquqes. These methods have recently led to seminal breakthroughs in force quantification for understanding oriented aggregation at the nanoscale. First, we detail two FIB milling based methods to fabricate AFM nanocrystal probes. One method requires careful pre-coating with a protective layer to avoid FIB damage to the face of interest, which is later chemically removed, and the other entails removal of the FIB damage layer with in situ polishing. We illustrate how to fabricate oriented nanocrystal force probes using commercial bulk crystals or nano/micro-crystals of calcite, zinc oxide, and rutile; the methods are fully transferrable to the apatites comprising bone minerals. The typical protocol for fabricating one AFM crystal probe takes 2-3 h. Finally, we describe how to measure interaction forces between nanocrystals in solution conditions of interest by performing AFM based DFS, or in the controlled environment of ETEM, using the resulting oriented nanocrystal probes. In addition, we illustrate how to quantify the direction-specific interaction forces for a given pair of interacting oriented nanocrystal faces, and how to relate this information generally to understanding crystallization by particle attachment.

Zhang, Xin (ORCID:000000032000858X)↗

DOE OSTI2020

Horizon radiation reaction forces

Using Effective Field Theory (EFT) methods, we compute the effects of horizon dissipation on the gravitational interactions of relativistic binary black hole systems. We assume that the dynamics is perturbative, i.e it admits an expansion in powers of Newton’s constant (post-Minkowskian, or PM, approximation). As applications, we compute corrections to the scattering angle in a black hole collision due to dissipative effects to leading PM order, as well as the post-Newtonian (PN) corrections to the equations of motion of binary black holes in non-relativistic orbits, which represents the leading order finite size effect in the equations of motion. The methods developed here are also applicable to the case of more general compact objects, eg. neutron stars, where the magnitude of the dissipative effects depends on non-gravitational physics (e.g, the equation of state for nuclear matter).

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2017

FleCSPH - a parallel and distributed SPH implementation based on the FleCSI framework

FleCSPH is a multi-physics compact application that exercises FleCSI parallel data structures for tree-based particle methods. In particular, FleCSPH implements a smoothed-particle hydrodynamics (SPH) solver for the solution of Lagrangian problems in astrophysics and cosmology. FleCSPH includes support for gravitational forces using the fast multipole method (FMM).

Junghans, Christoph↗

DOE OSTI2017

FleCSPH - a parallel and distributed SPH implementation based on the FleCSI framework

Junghans, Christoph↗

DOE OSTI2025

Search for monopole-dipole interactions with atom interferometry

Light, weakly coupled bosonic particles such as axions can mediate long range monopole-dipole interactions between matter and spins. We propose a new experimental method to detect such a force exerted by the spin of electrons on a freely falling atom using atom interferometry. The intrinsic advantages of atom interferometry, such as the freely falling nature of the atom and the well-defined response of the atom to external magnetic fields, should enable the proposed method to overcome systematic effects induced by vibrations, magnetic fields, and gravity. This approach is most suited to probe forces with a range ≳ 10 cm. With current technology, our proposed setup could potentially extend probes of such forces by an order of magnitude beyond present laboratory limits.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Alternative Technology for Creating Nanostructures Using Dip Pen Nanolithography

For modern microelectronics, at the present time, the technologies of consciousness smart structures play an important role, which can provide accuracy, stability and high quality of the structures. Submicron lithography methods are quite expensive and have natural size limitations, not allowing the production of structures with an extremely small lateral limitation. Therefore, an intensive search was conducted for alternative methods for creating submicron resolution structures. Especially attractive one is the possibility of self-organization effects utilization, where the nanostructure of a certain size is formed under the influence of internal forces. The dip pen nanolithography method based on a scanning probe microscope uses a directwrite technology and allows one to carry out a playback of small size structures with high accuracy. In the experiment, a substrate coated with Au (15 nm) using a DPN technique is applied to the polymer to form a desired pattern nano-sized channel. The experiment was conducted using a pointed probe SiN, coated MHA-Acetonitrile, on the Si(111)/Fe{sub 3}Si/Au structure.

36 MATERIALS SCIENCE↗

DOE OSTI2024

Identification of Kelvin-Helmholtz generated vortices in magnetised fluids

The Kelvin-Helmholtz Instability (KHI), arising from velocity shear across the magnetopause, plays a significant role in the viscous-like transfer of mass, momentum, and energy from the shocked solar wind into the magnetosphere. While the KHI leads to growth of surface waves and vortices, suitable detection methods for these applicable to magnetohydrodynamics (MHD) are currently lacking. A novel method is derived based on the well-established λ-family of hydrodynamic vortex identification techniques, which define a vortex as a local minimum in an adapted pressure field. The J × B Lorentz force is incorporated into this method by using an effective total pressure in MHD, including both magnetic pressure and a pressure-like part of the magnetic tension derived from a Helmholtz decomposition. The λ MHD method is shown to comprise of four physical effects: vortical momentum, density gradients, fluid compressibility, and the rotational part of the magnetic tension. A local three-dimensional MHD simulation representative of near-flank magnetopause conditions (plasma β’s 0.5 – 5 and convective Mach numbers M f ∼ 0.4) under northward interplanetary magnetic field (IMF) is used to validate λ MHD . Analysis shows it correlates well with hydrodynamic vortex definitions, though the level of correlation decreases with vortex evolution. Overall, vortical momentum dominates λ MHD at all times. During the linear growth phase, density gradients act to oppose vortex formation. By the highly nonlinear stage, the formation of small-scale structures leads to a rising importance of the magnetic tension. Compressibility was found to be insignificant throughout. Finally, a demonstration of this method adapted to tetrahedral spacecraft observations is performed.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2021

Pore-scale CFD simulations of clay mobilization in natural porous media due to fresh water injection

The present work investigates mechanisms of permeability impairment as a result of low-salinity fluid injection into brine-saturated porous media containing dispersible clays. Here, we present a computational fluid dynamics model at the pore-scale to simulate detachment, migration and straining of fine particles in porous media. The model uses an immersed boundary method to simulate the motion of clay fines in a fluid. In addition to the hydrodynamic forces, we model the Derjaguin-Landau-Verwey-Overbeek forces (DLVO) between clay fines and grains. Our simulations show the impact of the injected fluid's salinity and velocity on the concentration of clay fines retained on the grain surface. We see clay particles dislodging from the grain surface in clusters of up to 12 particles. Our simulation results also demonstrate clogging of narrow pore spaces by the detached particles from the grain surfaces.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2016

Contact stiffness and damping of liquid films in dynamic atomic force microscope

The mechanical properties and dissipation behaviors of nanometers confined liquid films have been long-standing interests in surface force measurements. The correlation between the contact stiffness and damping of the nanoconfined film is still not well understood. We establish a novel computational framework through molecular dynamics (MD) simulation for the first time to study small-amplitude dynamic atomic force microscopy (dynamic AFM) in a simple nonpolar liquid. Through introducing a tip driven dynamics to mimic the mechanical oscillations of the dynamic AFM tip-cantilever assembly, we find that the contact stiffness and damping of the confined film exhibit distinct oscillations within 6-7 monolayer distances, and they are generally out-of-phase. For the solid-like film with integer monolayer thickness, further compression of the film before layering transition leads to higher stiffness and lower damping, while much lower stiffness and higher damping occur at non-integer monolayer distances. These two alternating mechanisms dominate the mechanical properties and dissipation behaviors of simple liquid films under cyclic elastic compression and inelastic squeeze-out. Our MD simulations provide a direct picture of correlations between the structural property, mechanical stiffness, and dissipation behavior of the nanoconfined film.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2022

A Feasibility Study on Use of an Accelerometer to Measure the Dynamic Forces in Turning

Metal cutting is a highly dynamic process that generates continuously varying forces. Measurement of these forces is essential to characterizing a cutting process and to fully utilize the machine tool. A force dynamometer is often used to measure these varying forces; however, it is limited by the natural frequency of the sensor and can sometimes be hard to set up on a machine. Therefore, this study aims to estimate the dynamic component of the cutting force using an accelerometer placed directly below the cutting edge. The placement of the sensor helps achieving better signal to noise ratio (S/N). The cutting tool is modelled as a single degree of freedom (SDOF) system relative to the workpiece and dynamic loads are experimentally simulated on it. The measured acceleration is numerically integrated to obtain velocity and deflection, which along with the natural frequency (ω n ) and damping ratio (ζ), is used to predict the dynamic load using the system equation. The dynamic forces tested over a wide range of frequencies, show good agreement with the data from simultaneous dynamometer measurement and the force estimated using the proposed method. The study shows the feasibility of this method in a real cutting scenario and the capability to apply it to a multi DOF system. One major limitation is the inability to capture the static or quasi-static component of the cutting force.

Cutting vibrations↗

DOE OSTI2023

System and method for roll-to-roll film tensioning for reduced separation force during bottom-up stereolithography

The present disclosure relates to a tensioning system for use in a stereolithography manufacturing application. The system may have a build plate for supporting a three dimensional part being formed using a photo responsive resin, a base plate and a release element extending over the base plate. The release element is configured to receive a quantity of photo responsive resin for forming a new material layer of the three dimensional part. A pair of tensioning components are secured to opposite ends of the release element, and apply a controlled tension force to the release element during peeling of the release element to reduce a separation force required to separate the release element from the new material layer after the new material layer is cured.

Duoss, Eric B.↗