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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 1,189 records · Page 66

An Optimized Trajectory for a Two-Stage, Surface to Orbit Titan Launch Vehicle

As part of a NIAC funded Titan sample return mission, NASA GRC’s Compass Team has investigated a two-stage, in-situ propellant, launch vehicle design. This paper presents a proposed trajectory for the vehicle and mission of interest. This trajectory is optimally solved to balance drag losses in the denser atmosphere along with gravity losses accumulated during vehicle ascent to select an optimal path from Titan’s surface to a parking orbit. The resulting trajectory is characterized by a slow, vertical climb to an altitude above the densest part of the atmosphere followed by a vehicle pitch-over and climb to orbital insertion. The resulting ∆V is 3.96 km/s.

trajectory↗

NASA Engineering and Safety Center Technical Bulletin No. 22-05: Launch Vehicle Flight Control Stability Margin Reduction Considerations

Launch vehicle ascent stability analyses typically rely on a combination of frequency and time domain analyses. Frequency domain analysis uses a sequence of high-fidelity linear models with constant parameters spanning the ascent trajectory. Complementary time domain analysis is performed using high-fidelity, nonlinear 6-DOF simulations. Analyses are typically dispersed to verify robustness to parameter variations by showing the vehicle meets frequency domain stability margin requirements and time domain performance metrics. This Technical Bulletin outlines standard stability margin best practices and provides recommendations for treatment of deviations from industry-standard launch vehicle stability margins due to vehicle flexibility, slosh dynamics, aerodynamics, other offending dynamics, or coupling thereof.

Launch Vehicle↗

Energy Augmentation Concepts for Advanced Airspace Mobility Vehicles

This introductory paper describes several concepts that could be used for augmenting the energy state of electric Vertical Take-Off and Landing (eVTOL) vehicles. Advanced Air Mobility (AAM) electric vehicles, just like conventional vehicles, could need additional charge due to depleted batteries (e.g., strong winds along the way) while approaching their destination. There are three indirect charging and five direct charging concepts presented in this paper. The concepts are in preliminary research stage and are being refined. Considering the concepts are for the year 2045 timeframe, there is sufficient time to evolve them, along with the designs of the AAM vehicles. The paper describes more details and discussion on the desirability, viability, and feasibility of these energy augmentation concepts. A discussion of barriers and initial investigation approach for three concepts is presented.

AAM vehicles↗

Energy Augmentation Concepts for Advanced Airspace Mobility Vehicles

This introductory paper describes several concepts that could be used for augmenting the energy state of electric Vertical Take-Off and Landing (eVTOL) vehicles. Advanced Air Mobility (AAM) electric vehicles, just like conventional vehicles, could need additional charge due to depleted batteries (e.g., strong winds along the way) while approaching their destination. There are three indirect charging and five direct charging concepts presented in this paper. The concepts are in preliminary research stage and are being refined. Considering the concepts are for the year 2045 timeframe, there is sufficient time to evolve them, along with the designs of the AAM vehicles. The paper describes more details and discussion on the desirability, viability, and feasibility of these energy augmentation concepts. A discussion of barriers and initial investigation approach for three concepts is presented.

AAM vehicles↗

Atmospheric Mining in the Outer Solar System: Interplanetary Transfer Vehicles, In-Situ Resource Utilization, and Moon Mining Issues

Atmospheric mining in the outer solar system has been investigated as a means of fuel production for high energy propulsion and power. Fusion fuels such as Helium 3 (3He) and deuterium can be wrested from the atmospheres of Uranus and Neptune and either returned to Earth or used in-situ for energy production. Helium 3 and deuterium were the primary gases of interest with hydrogen being the primary propellant for nuclear thermal solid core and gas core rocket-based atmospheric flight. A series of analyses were undertaken to investigate resource capturing aspects of atmospheric mining in the outer solar system. This included the gas capturing rate, storage options, and different methods of direct use of the captured gases. While capturing 3He, large amounts of hydrogen and 4He are produced. With these two additional gases, the potential for fueling small and large fleets of additional exploration and exploitation vehicles exists. Analyses of orbital transfer vehicles (OTVs), landers, and in-situ resource utilization (ISRU) mining factories are included. Preliminary observations are presented on near-optimal selections of moon base orbital locations, OTV power levels, and OTV and lander rendezvous points. Aerospacecraft with closed cycle gas core propulsion are used to capture the 3He and deuterium from the outer planet atmospheres. Water ice on the outer planet moons has been identified as critical resources for refueling the moon landers and the nuclear electric OTVs. The numbers of interplanetary transfer vehicles (ITVs) and the launch vehicles will be presented. Preliminary design parameters for the ITVs and their payload limits will be assessed. The number of mining machines and their associated issues are addressed.

chemical propulsion↗

Natural Gas Vehicle Basics

Natural gas powers about 175,000 U.S. vehicles and more than 23 million vehicles worldwide [1]. Natural gas vehicles (NGVs) are a good choice for high-mileage (high fuel-use) fleets - such as buses, medium- and heavy-duty trucks, and refuse vehicles - that are centrally fueled or operate within a limited area or along a route with natural gas fueling stations. The advantages of natural gas as an alternative fuel include its domestic production, established distribution network, relatively low cost, and emissions benefits.

30 DIRECT ENERGY CONVERSION↗

RouteE: A Vehicle Energy Consumption Prediction Engine

The emergence of connected and automated vehicles and smart cities technologies create the opportunity for new mobility modes and routing decision tools, among many others. To achieve maximum mobility and minimum energy consumption, it is critical to understand the energy cost of decisions and optimize accordingly. The Route Energy prediction model (RouteE) enables accurate estimation of energy consumption for a variety of vehicle types over trips or sub-trips where detailed drive cycle data are unavailable. Applications include vehicle route selection, energy accounting and optimization in transportation simulation, and corridor energy analyses, among others. The software is a Python package that includes a variety of pre-trained models from the National Renewable Energy Laboratory (NREL). However, RouteE also enables users to train custom models using their own data sets, making it a robust and valuable tool for both fast calculations and rigorous, data-rich research efforts. The pre-trained RouteE models are established using NREL's Future Automotive Systems Technology Simulator paired with approximately 1 million miles of drive cycle data from the Transportation Secure Data Center, resulting in energy consumption behavior estimates over a representative sample of driving conditions for the United States. Validations have been performed using on-road fuel consumption data for conventional and electrified vehicle powertrains. Transferring the results of the on-road validation to a larger set of real-world origin-destination pairs, it is estimated that implementing the present methodology in a green-routing application would accurately select the route that consumes the least fuel 90% of the time. The novel machine learning techniques used in RouteE make it a flexible and robust tool for a variety of transportation applications.

47 OTHER INSTRUMENTATION↗

Perspectives on Charging Medium- and Heavy-Duty Electric Vehicles

Electric vehicles (EVs) adoption is gaining momentum globally thanks to major technological advancements as well as policy actions and support from multiple stakeholders. EVs are well positioned to replace internal combustion engine vehicles for passenger cars, SUVs, vans, trucks, and buses, but a plethora of solutions is needed to provide effective, convenient, and affordable charging to different vehicles and for various applications. This talk focuses on charging of medium and heavy-duty vehicles, the second largest source of US transportation GHG emissions, providing an overview of charging needs for different applications. Moreover, we offer a deep dive on depot charging solutions for short-haul heavy-duty trucks based on a recent Nature Energy paper.

ADVANCED PROPULSION SYSTEMS↗

Aligning Electric Vehicle Customer Charging with Grid Needs

This talk to the National Association of Regulatory Utility Commissioners (NARUC) focuses on "Aligning Electric Vehicle Customer Charging with Grid Needs" to highlight the opportunities associated with managed electric vehicle charging and its value for consumers and the power system. Electric vehicles (EVs) are experiencing a rapid rise in popularity and adoption, and growing EV adoption offers an opportunity to increase electricity demand. With expected widespread EV adoption, supporting charging will require investments in generation, transmission, and distribution systems. Uncoordinated charging of EVs will lead to increased system peak load, possibly exceeding the maximum power that can be supported by distribution systems and generally increasing power system stress. However, vehicles are underutilized assets parked ~96% of the time: managed EV charging can satisfy mobility needs while also supporting the grid. EVs are not a burden for the grid, but a resource: The demand-side flexibility provided by managed EV charging offers significant potential benefits for the grid over multiple timescales and applications., especially for high-renewable systems. Managed charging can support power system planning and operations during normal and extreme conditions, benefitting EV owners and other electricity consumers. Managed charging is shown to consistently provide hundreds of dollars in cost savings per EV each year.

ADVANCED PROPULSION SYSTEMS↗

Electric Vehicles for Consumers

More consumers are choosing electric vehicles (EVs) as new, competitively priced models with longer ranges hit the market. More public charging stations are also rapidly becoming available, and some offer quick charges to get drivers back on the road in minutes. New EVs are released all the time, with models designed to meet a wider variety of needs. To learn whether an EV is right for you, assess your driving requirements, available vehicles, and cost considerations. Easily compare costs and benefits of specific vehicles using the FuelEconomy.gov vehicle comparison tool.

ADVANCED PROPULSION SYSTEMS↗

At a Glance: Electric Vehicles

Electric vehicles (EVs) include all-electric vehicles - also referred to as battery electric vehicles (BEVs) - and plug-in hybrid electric vehicles (PHEVs).

ADVANCED PROPULSION SYSTEMS↗

At a Glance: Electric Vehicles (French Translation)

Electric vehicles (EVs) include all-electric vehicles - also referred to as battery electric vehicles (BEVs) - and plug-in hybrid electric vehicles (PHEVs). This is the French translation of NREL/FS-5400-87123 (https://www.nrel.gov/docs/fy23osti/87123.pdf).

ADVANCED PROPULSION SYSTEMS↗

Power Quality and Load Capacity Evaluations of an Electric Vehicle for Multi-Robot System Applications

This paper evaluates the capability of a fully electric pickup truck, using the Ford F-150 Lightning as an example, to provide power to the circuit of a multi-robot system. The case study was conducted on a simulated INL Autonomous Pit Exploration System (APES) designed for the inspection of nuclear waste tank pits. Through a series of controlled tests, the vehicle’s power delivery consistency, load-handling capability, and battery performance were assessed under various conditions. First of all, the load test demonstrated that the vehicle provided stable power with low distortion and no unexpected interruptions. Second, during the operational limit test, the 240V system sustained loads up to 7.4 kW before tripping, providing insights into its operational limits. Last but not least, during a simulated full-scale APES operation, the vehicle’s battery depleted by only 6% over an hour, indicating sufficient capacity for extended use while retaining reserve power for transportation needs. This study highlights the potential of electric vehicles as reliable power sources for field operations, contributing to the advancement of sustainable technologies by reducing reliance on traditional fossil fuel generators and promoting the integration of clean energy solutions in remote and challenging environments.

Electric vehicle↗

Vehicle Technologies and Hydrogen and Fuel Cell Technologies Research and Development Programs Benefits Assessment Report for 2020

The U.S. Department of Energy’s Vehicle Technologies and Hydrogen and Fuel Cell Technologies Offices (VTO and HFTO) support research and development of efficient and sustainable transportation technologies that will improve energy efficiency, minimize emissions, and enable America to use less petroleum. VTO and HFTO regularly revisit and update relevant research and development goals and areas of emphasis in response to the latest technological advancements and in alignment with current national priorities. As such, analyses of expected benefits resulting from VTO and HFTO investments and anticipated goal achievements are updated periodically and will be again for 2021 in the context of the latest national-level transportation decarbonization goals. The analysis in the present report is based on technical progress goals established in VTO and HFTO in the years immediately prior to and including 2020, and it summarizes the estimated energy and emissions benefits corresponding to achievement of those goals. The goals span research activities on batteries, electric drive technologies (EDT), combustion, lightweight materials, fuel cells, and hydrogen storage. The evaluation includes detailed analyses into the benefits of technology improvements on the U.S. light-duty (LD) vehicle fleet and separately on the U.S. medium- and heavy-duty (MDHD) vehicle fleet. This report summarizes the outcomes from each of these analyses both independently and in combination.

08 HYDROGEN↗

Electric Vehicle Infrastructure Consequence Assessment

With consumers’ growing interest in electric vehicles, extreme fast charging stations are poised to provide high-power charging to rapidly recharge light-duty passenger vehicles. High-power charging requires high-level communication between vehicle and charger to govern the charging process. The coupling of power and communication increases the potential scale of cyberattacks. Using a full Western Electricity Coordinating Council planning model, load manipulation from high-power charging infrastructure is investigated. Two cases of load manipulation are studied: (i) a discrete, widespread system event and (ii) loads modulated near the Western Interconnect’s resonant frequency. In (i) some generation trips and in (ii) oscillations are observed on the California Oregon Intertie. Neither scenario results in significant adverse effects to the grid.

33 ADVANCED PROPULSION SYSTEMS↗

A Report on Actions for Medium- and Heavy-Duty Vehicle Energy and Emissions Innovation

A Report on Actions for Medium- and Heavy-Duty Vehicle Energy and Emissions Innovation (the MHDV Plan) summarizes strategies and actions to substantially reduce emissions in the U.S. commercial on-road medium- and heavy-duty vehicle (MHDV) sector. This includes all on-road vehicles over 8,500 pounds used for commercial purposes. The intended audience of this report are industry and stakeholders who will take on the suite of actions needed to drive forward MHDV emissions reduction and decarbonization in a sustainable and economic way.

33 ADVANCED PROPULSION SYSTEMS↗

Understanding the Charging Flexibility of Shared Automated Electric Vehicle Fleets

The combined anticipated trends of vehicle sharing (ride-hailing), automated control, and powertrain electrification are poised to disrupt the current paradigm of predominately owner-driven gasoline vehicles with low levels of utilization. Shared, automated, electric vehicle (SAEV) fleets offer the potential for lower cost and emissions and have garnered significant interest among the research community. While promising, unmanaged operation of these fleets may lead to unintended negative consequences. One potentially unintended consequence is a high quantity of SAEVs charging during peak demand hours on the electric grid, potentially increasing the required generation capacity. This research explores the flexibility associated with charging loads demanded by SAEV fleets in response to servicing personal mobility travel demands. Travel demand is synthesized in four major United States metropolitan areas: Detroit, MI; Austin, TX; Washington, DC; and Miami, FL. In each of these four cities, SAEV simulations are performed using local projected electricity prices from the Regional Energy Deployment System (ReEDS) for a handful of supply side scenarios. A coordinated charging model is introduced that seeks to reduce fleet charging costs in response to time-varying electricity prices and increasing shares of personal trip demand served (between 1% and 25% of all metro trips served by the SAEV fleet). Simulation results are presented across various scenarios assuming fleetwide coordination to minimize charging energy costs while constrained by offering adequate mobility service to fleet customers. The results indicate that the SAEV charging load is highly flexible; energy costs were shown to reduce between 13% and 46% across a wide range of simulated scenarios. In addition, these savings were realized without detrimentally impacting the fleet’s ability to service trips.

autonomous vehicle↗

Electric Vehicles for Fleets

Electric vehicles can fulfill many daily driving needs, making them a great solution for fleets. They offer several benefits and can fill roles in light-duty, medium-/heavy-duty (MD/HD), and even off-road applications. The unique fleet environment presents considerations beyond those that consumers must address before going electric. For example, fleet managers must understand the impacts of charging multiple vehicles while maintaining fleet operations. Larger MD/HD vehicles bring additional factors to consider.

charging↗