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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.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

¡Viva la mitochondria!: harnessing yeast mitochondria for chemical production

ABSTRACT The mitochondria, often referred to as the powerhouse of the cell, offer a unique physicochemical environment enriched with a distinct set of enzymes, metabolites and cofactors ready to be exploited for metabolic engineering. In this review, we discuss how the mitochondrion has been engineered in the traditional sense of metabolic engineering or completely bypassed for chemical production. We then describe the more recent approach of harnessing the mitochondria to compartmentalize engineered metabolic pathways, including for the production of alcohols, terpenoids, sterols, organic acids and other valuable products. We explain the different mechanisms by which mitochondrial compartmentalization benefits engineered metabolic pathways to boost chemical production. Finally, we discuss the key challenges that need to be overcome to expand the applicability of mitochondrial engineering and reach the full potential of this emerging field.

Biotechnology & Applied Microbiology↗
DOE OSTI2021

Harnessing Photoelectrochemistry for Wastewater Nitrate Treatment Coupled with Resource Recovery

Wastewater is a misplaced resource well suited to recover nutrients, value-added chemicals, energy, and clean water. A photoelectrochemical device is proposed to transform wastewater nitrates to ammonia and nitrous oxide, coupled with water oxidation. Numerical models were developed to quantify the dependence of process efficiencies and nitrogen-removal rates on light absorber band gaps, electrocatalytic kinetic parameters, competing oxygen reduction and hydrogen evolution reactions, and the reacting nitrate species concentrations that affect the mass-transfer limited current densities. With a single light-absorber and state-of-the-art catalysts, optimal solar-to-chemical efficiencies of 7% and 10% and nitrogen-removal rates of 260 and 395 gN m -2 day -1 are predicted for nitrate reduction to ammonia and nitrous oxide, respectively. The influence of competing reactions on the performance depends on the nitrate concentration and band gap of the light absorber modeled. Oxygen reduction is more dominant than hydrogen evolution to compete with the nitrate reduction reaction, but it is mass-transfer limited. Even with kinetic parameters that enhanced the driving forces for the competing reactions, the performance is only minimally affected by these reactions for optimally selected band gaps and nitrate concentrations larger than 100 mM. Here, theoretically predicted peak nitrogen removal rates and specific energy intensities are competitive with reported estimates for electrochemical and Sharon-Anammox processes for ammonia recovery and nitrogen removal, respectively. This result, together with the added benefit of harnessing sunlight to produce value-added products, indicates promise in the photoelectrochemical approach as a tertiary pathway to recover nutrients and energy from wastewater nitrates.

25 ENERGY STORAGE↗
DOE OSTI2019

Adaptive harnessing damping in hydrokinetic energy conversion by two rough tandem-cylinders using flow-induced vibrations

Alternating lift technology (ALT) harnesses hydrokinetic energy from currents and tides and is different from conventional steady lift technologies (turbines). ALT is still under development with an important research issue being the mitigation of wake effect on downstream cylinders in Flow Induced Oscillations (FIO) of multi-cylinder Current Energy Converters (CEC). Rather than adjust the configuration/parameters of the converter, a more direct and effective way is to actively adjust the harnessed power. In this paper, a hydrokinetic energy converter using FIO of two cylinders in tandem in one-degree-of-freedom oscillators, with nonlinear adaptive damping and linear spring stiffness, is tested experimentally. FIO include Vortex Induced Vibrations (VIV), galloping, and their coexistence. Introducing adaptive damping into the tandem cylinders overcomes the shielding effect, which previous research on two tandem cylinders has shown to reduce power output by the downstream cylinder. Shielding along with fixed damping result either in ceasing motion due to excessive damping, or in low harnessed energy due to insufficient damping. In this experimental study, damping-to-velocity rate, linear spring-stiffness, cylinder spacing, and flow-velocity are the parameters with Reynolds number 30,000 ≤ Re ≤ 120,000. Comparison to linear-oscillators in FIO shows that this nonlinear converter, with velocity-proportional damping coefficient, is more effective over the entire FIO range but especially in galloping, where both flow and cylinder speeds are higher. Experimental results for energy harvesting, efficiency and instantaneous energy of the converter are presented and discussed supported by amplitude and frequency response data. Here the results show that the nonlinear, adaptive, velocity-proportional damping coefficient is an effective way to increase the overall harnessed power and the power of downstream cylinder. The harnessed power in the VIV to galloping transition increases by up to 94%. The most significant improvement is in the galloping region, where the increase in harnessed power and efficiency is around 33%.

13 HYDRO ENERGY↗
DOE OSTI2019

Bio-Inspired adaptive damping in hydrokinetic energy harnessing using flow-induced oscillations

A hydrokinetic energy converter using Flow Induced Oscillations (FIOs) of a one-degree-of-freedom cylinder-oscillator, with nonlinear adaptive damping and linear spring stiffness, is introduced and studied experimentally. Comparison to a linear-oscillator in FIO shows that this new converter, with velocity-proportional damping coefficient, is more effective in galloping, where both flow and cylinder speeds are higher. It also impacts VIV, since the converter is no longer restricted by fixed damping, which results either in ceasing motion due to excessive damping, or in low harnessed energy due to insufficient damping. The impact is most profound in the VIV to galloping transition where adaptive damping prevents shutting down of hydrokinetic energy conversion. Damping-to-velocity rate, linear spring-stiffness, and flow-velocity are the experimental parameters with Reynolds number 30,000 ≤ Re ≤ 120,000. Here, experimental results for amplitude response, frequency response, energy harvesting, efficiency and instantaneous energy of the converter are presented and discussed. The main conclusions are: (1) The nonlinear, adaptive, velocity-proportional damping coefficient increases the harnessed power. (2) The operational range of flow velocities increases. (3) At lower flow speeds, the adaptive damping stabilizes the unstable oscillations typically occurring in this region. (4) At higher flow speeds, adaptive damping results in higher harnessed power than constant damping, thus, better emulating passively a corresponding, natural, active motion by fish. (5) Increase of 51%–95% in converted power by the nonlinear oscillator compared to linear oscillator has been measured. (6) The adaptive damping converter reaches a plateau in harnessed efficiency at high flow velocity (fully developed galloping).

13 HYDRO ENERGY↗
DOE OSTI2020

Harnessing the Hydroelectric Potential of Engineered Drops (Final Technical Report)

The potential for low-head hydropower in the engineered drops in both federal and private irrigation system is well known and significant. The environmental and socio/recreational impacts of harnessing this renewable energy resource in man-made conduits are much less, and often insignificant, compared with comparable hydro-electric potential in natural water features on rivers, lakes, and streams. Yet, few new plants have been commissioned in more than two decades. Over the same time period, low head hydro installations in Germany have more than doubled. The challenge is in finding economical ways to harness the hydro-electric potential in the engineered drops, and efficiently deliver the power to the grid. The objectives of Percheron Power, LLC's (Percheron Power) Project were to design, develop, permit, and operate an innovative low-head hydro-electric generation facility on an existing engineered drop of a large irrigation canal system. The hydro-electric generation facility was designed to employ a new type of turbine and technology, called an Archimedes Hydrodynamic Screw (AHS), to harness the existing potential of the engineered drop. The goal was to demonstrate the new lower cost AHS technology system to federal agencies, irrigation districts and other system owners and to support further development of new small hydropower projects at previously marginal low-head sites in the U.S. The objective of this funding opportunity of the Department of Energy Water Power Technologies Office was to reduce the Levelized Cost of Energy (LCOE) for small hydropower to less than ${$}$0.07/kWh (${$}$70/MWh) to be competitive with existing base-load power sources such as coal-powered power plants.

13 HYDRO ENERGY↗
DOE OSTI2026

Reining in an Agentic Harness for High Energy Physics

Agentic systems now address tasks across theoretical, phenomenological, and experimental high energy physics (HEP), but their scientific capabilities remain difficult to reuse across different large language models, providers, and harnesses. We argue that stable parts of these workflows should be promoted into versioned scientific operations and exposed through common protocols. Existing general-purpose harnesses can then be specialized for HEP through task-specific sets of tools and skills, while community-maintained registries would make these capabilities discoverable and citable. We identify mismatches in conventions, assumptions, and domains of validity among independently developed operations as a potential obstacle to their composition, and discuss machine-readable scientific contracts as one possible solution. These design principles and evaluation guidelines provide a near-term path toward a portable and community-maintained agentic harness for HEP.

Menzo, Tony [Alabama U.; Fermilab] (ORCID:00000002↗
DOE OSTI2021

A comprehensive review of nonlinear oscillators in hydrokinetic energy harnessing using flow-induced vibrations

A comprehensive review of hydrokinetic energy converters based on alternating lift technology (ALT) is provided. Emphasis is on nonlinear oscillators based on Flow Induced Vibration (FIV) or Oscillation (FIO). Due to strong coupling in Fluid-Structure Interaction (FSI), and in order to maximize the hydrokinetic harnessed energy, design of nonlinear oscillators and analysis by model tests or computational fluid dynamics dominates this area. Research confirmed that the nonlinear oscillator can harvest energy from a stochastic excitation modeled by a generic wide spectrum, and overcome the most severe oscillator limitations: specifically, the need for continuous frequency tuning due to the narrow bandwidth response, and low efficiency outside the narrow bandwidth oscillator response. This review covers the following aspects of nonlinear oscillators in ALT converters: (1) Geometric changes in oscillator cross-section; e.g., circular, square, rectangular, or trilateral shapes. (2) Passive turbulence control of FIV/FIO. (3) Position based nonlinear stiffness. (4) Multi-cylinder synergistic FIV/FIO. (5) Mechanically linked oscillators. (6) Velocity-based, nonlinear, adaptive harnessing damping.

42 ENGINEERING↗
DOE OSTI2019

Harmony: A Harness Monitoring System for the Oak Ridge Leadership Computing Facility

Acceptance of a new system requires extensive testing and is often comprised of hundreds of tests. Summit, the latest flagship super-computer at the Oak Ridge Leadership Computing Facility (OLCF), and the number one system in the November 2018 Top500 list [2], completed its acceptance testing in 2018. To execute acceptance, the acceptance test (AT) team utilizes the OLCF test harness, a tool developed at the OLCF that automates the launch and verification of all acceptance tests. Acceptance requires analysis of test results and classification of all test failures. The sheer number of tests involved makes performing these tasks challenging. To complete these tasks more efficiently, in addition to lessen the personnel burden during acceptance testing, we developed a monitoring system for the OLCF test harness called Harmony.

Kuchta, Cameron↗
DOE OSTI2018

Harnessing the Materials Project for machine-learning and accelerated discovery

We present that improvements in computational resources over the last decade are enabling a new era of computational prediction and design of novel materials. The resulting resources are databases such as the Materials Project (www.materialsproject.org), which is harnessing the power of supercomputing together with state-of-the-art quantum mechanical theory to compute the properties of all known inorganic materials, to design novel materials, and to make the data available for free to the community, together with online analysis and design algorithms. The current release contains data derived from quantum mechanical calculations for more than 70,000 materials and millions of associated materials properties. The software infrastructure carries out thousands of calculations per week, enabling screening and predictions for both novel solids as well as molecular species with targeted properties. As the rapid growth of accessible computed materials properties continues, the next frontier is harnessing that information for automated learning and accelerated discovery. Here, we highlight some of the emerging and exciting efforts, and successes, as well as current challenges using descriptor-based and machine-learning methods for data-accelerated materials design.

36 MATERIALS SCIENCE↗
DOE OSTI2019

“Lattice Strain Matching”‐Enabled Nanocomposite Design to Harness the Exceptional Mechanical Properties of Nanomaterials in Bulk Forms

Abstract Nanosized materials are known to have the ability to withstand ultralarge elastic strains (4–10%) and to have ultrahigh strengths approaching their theoretical limits. However, it is a long‐standing challenge to harnessing their exceptional intrinsic mechanical properties in bulk forms. This is commonly known as “the valley of death” in nanocomposite design. In 2013, a breakthrough was made to overcome this challenge by using a martensitic phase transforming matrix to create a composite in which ultralarge elastic lattice strains up to 6.7% are achieved in Nb nanoribbons embedded in it. This breakthrough was enabled by a novel concept of phase transformation assisted lattice strain matching between the uniform ultralarge elastic strains (4–10%) of nanomaterials and the uniform crystallographic lattice distortion strains (4–10%) of the martensitic phase transformation of the matrix. This novel concept has opened new opportunities for developing materials of exceptional mechanical properties or enhanced functional properties that are not possible before. The work in progress in this research over the past six years is reported.

Zhang, Junsong↗
DOE OSTI2024

Harnessing High‐Throughput Computational Methods to Accelerate the Discovery of Optimal Proton Conductors for High‐Performance and Durable Protonic Ceramic Electrochemical Cells

Abstract The pursuit of high‐performance and long‐lasting protonic ceramic electrochemical cells (PCECs) is impeded by the lack of efficient and enduring proton conductors. Conventional research approaches, predominantly based on a trial‐and‐error methodology, have proven to be demanding of resources and time‐consuming. Here, this work reports the findings in harnessing high‐throughput computational methods to expedite the discovery of optimal electrolytes for PCECs. This work methodically computes the oxygen vacancy formation energy (E V ), hydration energy (E H ), and the adsorption energies of H 2 O and CO 2 for a set of 932 oxide candidates. Notably, these findings highlight BaSn x Ce 0.8‐x Yb 0.2 O 3‐δ (BSCYb) as a prospective game‐changing contender, displaying superior proton conductivity and chemical resilience when compared to the well‐regarded BaZr x Ce 0.8‐x Y 0.1 Yb 0.1 O 3‐δ (BZCYYb) series. Experimental validations substantiate the computational predictions; PCECs incorporating BSCYb as the electrolyte achieved extraordinary peak power densities in the fuel cell mode (0.52 and 1.57 W cm −2 at 450 and 600 °C, respectively), a current density of 2.62 A cm −2 at 1.3 V and 600 °C in the electrolysis mode while demonstrating exceptional durability for over 1000‐h when exposed to 50% H 2 O. This research underscores the transformative potential of high‐throughput computational techniques in advancing the field of proton‐conducting oxides for sustainable power generation and hydrogen production.

08 HYDROGEN↗
DOE OSTI2023

Harnessing Electrochemical‐Mechanical Couplings to Improve the Reliability of Solid‐State Batteries

Abstract One key barrier to using lithium‐metal anode batteries is that metal dendrites can penetrate solid electrolytes, causing short‐circuits and battery failures. It is established that this failure is likely caused by crack propagation due to electrodeposition‐induced stresses from lithium metal. This study explores ways to harness these electrochemical‐mechanical couplings to control dendrite growth and improve battery reliability using a phase‐field model and targeted fracture experiments. The results show that dendrite growth can be effectively mitigated by applying mechanical stresses or tailoring the material's fracture toughness. This study also outlines the requirements for compressive stress to halt or deflect dendrites as a function of the overpotential and discusses the role of microstructure in this process.

Monismith, Scott↗