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NASA NTRSDate not supplied

Methods for Developing Successful Systems Engineers

Systems Engineering (SE) is a complex and challenging field that incorporates the knowledge of systems engineering processes, the ability to synthesize a wide-range of engineering disciplines, and the ability to lead a team of people to successfully accomplish the goals of a project. It requires hard technical skills and soft-skill leadership savvy. As a result, three main development needs are identified: 1. Knowledge of SE processes, the benefits of these processes to a project and their tailored application 2. Knowledge of a wide-range of engineering disciplines, how they interrelate in a system, and the development of sound technical judgement 3. Team leadership to direct and motivate a team of subsystem and discipline experts This paper describes the establishment of a comprehensive training and development program for Systems Engineers at NASA Ames Research Center that addresses in part each of these three areas from the perspective of the implementing manager. A variety of methods have been utilized including the establishment of a SE Community of Practice, a unique and innovative web tool, on-line videos, classroom training in NASA’s 17 Common Technical Processes, guidance on the tailored application of these processes, monthly technical talks, mentoring in both technical judgment and team leadership, and NASA’s Leadership Development Programs. While much of professional SE development must come through project experience, the approaches listed above can accelerate development. The diversity of skills required of Systems Engineering demands a multi-faceted approach to successfully train and develop this critical skill.

development↗

DOE OSTI2020

Measurement of engine-oil fuel dilution using laser induced florescence spectroscopy

An optical diagnostic, based on laser-induced fluorescence (LIF), has been developed for on-engine measurements of real-time fuel dilution of engine oil, or fuel in oil (FiO). Fuel dilution of oil is believed to be one of the underlying mechanisms that promotes low speed pre-ignition (LSPI) during high-load engine operations. While standard (e.g., ASTM D3524-90) methods are not capable of transient measurements, the LIF technique resolves transient dilution on the minutes time scale, making it possible to study the relation between FiO and LSPI. The measurement is based on adding a dye (ca. 500 ppm) to the fuel and monitoring for its presence in the oil via LIF. The instrument contains a 532-nm laser diode, and a spectrometer to resolve the LIF spectra. A fiber-optic assembly links the instrument to the engine measurement location; the probe is in a Y-configuration with the six fibers around one on a common probe end that connects to the engine; the Y-assembly legs are connected to the instrument; the two legs are the six fibers for transporting the laser light, and the single fiber for the fluorescence. We have expanded on our previous work (Parks et al, SAE paper 2007-01-4108, 2007), by demonstrating the diagnostic technique with to measure transient oil dilution on a 2.0-liter GM ECOTEC LNF single cylinder SI engine. The proposed LIF diagnostic will be critical in studying oil-dilution correlation with LSPI events.

Neupane, Sneha↗

DOE OSTI2023

Lubricant impacts on piston deposit formation in the Enterprise marine diesel research engine

The impact of lubricant formulation on piston deposits was studied using the Enterprise, a reduced-scale, single-cylinder, two-stroke crosshead marine diesel research engine. The Enterprise engine was specially designed for marine diesel lubricant research, with a custom reduced-scale cylinder lubricant injection system and extensive instrumentation of thermal boundary conditions on both the liner and piston. Lubricant conditions typical of full-scale marine diesel engines are obtained by matching mean piston speed, liner temperature profile, and combustion metrics to realistic values.Piston deposit thicknesses were measured after a set period of operation, with a focus on lubricant-based deposits on the lands and ring grooves, using both optical and contact-based measurement techniques. Engine operation for each lubricant was conducted according to a standardized protocol, with precise control of engine speed and load, cylinder lubricant injection rate, coolant temperatures, and system oil temperature; the liner and piston temperatures are continuously monitored during operation. After operation with each lubricant was completed, the engine was disassembled, and the piston and ring deposits were characterized. The piston was then thoroughly cleaned, and the lubricant system flushed, between each lubricant formulation being evaluated. The impacts on piston deposits of the lubricants being evaluated can thus be accurately quantified and are described herein.

Kaul, Brian↗

DOE OSTI2022

Passive selective catalytic reduction (SCR) system and method for low-temperature combustion (LTC) engine

A combustion mode module is configured to switch operation of a low-temperature combustion (LTC) engine between a spark ignition (SI) mode, a positive valve overlap (PVO) mode, and a negative valve overlap (NVO) mode. A spark control module is configured to control a spark plug to generate a spark in a cylinder of the LTC engine when the LTC engine is operating in the SI mode. A valve control module is configured to control intake and exhaust valves of the cylinder to yield a PVO and a NVO when the LTC engine is operating in the PVO mode and the NVO mode, respectively. An air/fuel (A/F) control module is configured to adjust a desired A/F ratio of the LTC engine to a rich A/F ratio when operation of the LTC engine is switched to the PVO mode from either one of the SI mode and the NVO mode.

Yun, Hanho↗

DOE OSTI2022

Technology Enablers for Advanced Gasoline Compression Ignition Engines

To meet current emission regulations and increasingly demanding global fleet CO2 standards on fuel economy and future trends towards life cycle GHG emissions, advanced combustion engines remain significant in the passenger vehicle sector to achieve high efficiency and low emissions over the full operating range. Lean burn gasoline compression ignition (GCI) technology has shown to have the most potential in reaching these goals, although it faces challenges in the operating range. In this study, an advanced GCI engine is considered with the capability to operate under two combustion modes, namely low temperature combustion (LTC) and GCI. They are enabled with the use of two Hyundai in-house developed technologies; an advanced valve control mechanism known as continuously variable valve duration (CVVD) and a high-pressure gasoline injection system. At low load, the engine utilizes dual CVVD and dual CVVT (continuously variable valve timing) mechanisms for both intake and exhaust valvetrains to enable NVO (negative valve overlap) to trap hot residuals. The hot residuals enable low load auto-ignition, and the phasing control of that auto-ignition is achieved by varying the degrees of NVO, and in turn, the amount of hot residuals. This is done in real time with respect to the changes in engine loads or operating conditions, significantly improving cylinder-phasing control in LTC mode, and subsequently is able to realize a fuel economy gain and reduced emission benefits. Early direct injection during NVO or intake stroke is used to form homogenous or quasi-homogenous air-fuel mixture for LTC. At mid to high loads, late direct injection of gasoline or GCI mode is employed to take advantage of the high volatility and high resistance to auto-ignition of gasoline fuel, so that diesel-engine like high combustion efficiency can be achieved with lower soot emissions for the same NOx level as diesel combustion. In this paper, the key control and fueling technologies that enable this multiple mode combustion are introduced, and the resultant analysis on engine test and CFD simulation at LTC and GCI operating conditions are presented in detail.

Gasoline compression ignition, low temperature com↗

DOE OSTI2024

Heat exchanger(s) for recovering water and/or heat energy from turbine engine combustion products

A turbine engine is provided that includes a fan section, a turbine engine core and a recovery system. The turbine engine core is configured to power the fan section. The turbine engine core includes a core compressor section, a core combustor section and a core turbine section. A centerline axis of the turbine engine core is offset from a centerline axis of the turbine engine. The recovery system includes an evaporator module and a condenser module. A core flowpath extends sequentially through the core compressor section, the core combustor section, the core turbine section, the evaporator module and the condenser module from an inlet into the core flowpath to an exhaust from the core flowpath.

Sobanski, Jon E.↗

DOE OSTI2025

Evaluating Chemical Kinetics Predictions for Propane Using 3-D and 0-D Models in a Boosted Spark-Ignited Engine

Propane has been shown to be a promising alternative fuel to reduce emissions while simultaneously achieving high efficiencies in medium- and heavy-duty engines. These high-power density applications require boosted engines which, combined with high compression ratio, can lead to auto-ignition and knock. While three-dimensional (3-D) computational fluid dynamics (CFD) models are often used for resolving the complex fluid flow in engines, these models can become computationally expensive when simulating detailed chemical kinetics. Likewise, zero-dimensional (0-D) models are computationally concise enough for kinetics development, but lack any flow-field information which governs the flame propagation processes in spark ignition (SI) engines. This work presents a comprehensive comparison between 3-D and 0-D closed cycle simulations at knocking conditions in a high compression ratio high stroke-to-bore ratio propane engine. In order to initialize the flow-field for the 3-D closed cycle (intake valve closing, (IVC) to exhaust valve opening, (EVO)) simulation, a motored multi-cycle 3-D model was run using Converge to create a map at IVC, reducing the computational time. The map allowed a non-homogeneous 3-D closed cycle simulation to be satisfactorily validated against experiments, while a homogeneous case using only the turbulence field mapping was also simulated, mimicking 0-D modeling. The 3-D simulations were used to prescribe the initial conditions (e.g., IVC thermodynamics, speciation, burn-rate profile) for a 2-zone 0-D SI engine model in Chemkin Pro for both cases. It was found that 2-zone 0-D modeling underpredicted the knock onset timing, likely due to the lack of thermal stratification in the unburned gas region. Future work will carry multi-zone 0-D modeling to capture the fuel auto-ignition in the unburned region.

Douvry-Rabjeau, Julien [Oakland University, Roches↗

DOE OSTI2020

Portable interactive visualization of large-scale simulations in geotechnical engineering using Unity3D

Development in large-scale geotechnical engineering simulation places tremendous demand for efficient visualization of such simulation data. This study presents a lightweight software tool, i.e. Geotechnical Interactive Visualization (GIV), as a solution to this challenge, which achieves efficient interactive visualization of large-scale simulations data in geotechnical engineering. Visualization data flow and algorithms specifically optimized for common geotechnical engineering applications are implemented in GIV. GIV can visualize geotechnical structure models with time-varying attributes attached to mesh with fixed topology, and also models with time-varying mesh topologies but no attributes attached, the two most common visualization tasks in geotechnical engineering. Furthermore, challenges for large-scale simulation data visualization, including parallel simulation data redundancy, massive data size, dynamic user interaction, and portability are overcome via specifically designed algorithms for simulation data preprocessing and optimized visualization modules using the powerful 3D rendering and interactive game engine Unity3D. Comparison of GIV with several widely used visualization tools for the visualization of large-scale idealized datasets and realistic geotechnical simulations highlights the visualization efficiency, smooth interactivity, and lightweight features of GIV.

42 ENGINEERING↗

DOE OSTI2026

MARVEL Reactor Digital Engineering Developments

The MARVEL reactor project has served to introduce a new generation of engineers to the processes required to transform a reactor design from simply an idea on paper into what will be an approved, constructed, and operational nuclear power system. Much as there have been advances in materials, analysis, and evaluation methodologies over the 50 years since the last reactor was built at INL, so too has the technology for managing the engineering process itself advanced. Digital Engineering tools and methods provide improved coordination between previously siloed engineering disciplines, reduced burdens of non-value-added data transcription processes and bring forward insights and improvements that might otherwise fall later in the design stage, where changes are much more costly. While the tools and techniques to support the full digital engineering vision are not yet complete, the MARVEL design processes provide valuable demonstrations and validations of key aspects and illuminate further areas for implementation by subsequent projects.

21 - SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLAN↗

DOE OSTI2024

The Digital Engineering Vision for DOME: Facilitating Design, Deployment, and Operations [Poster]

DOME is a planned microreactor test facility at INL’s Materials and Fuels Complex. It is a complex system with several interdependent sub-systems such as the reactor (up to 20 MWth), radioactive confinement, temperature and pressure regulation system, ventilation system, etc. The engineering design process for such a system traditionally involves several documents from various sources and the system information is scattered across these documents. Digital engineering represents a paradigm shift through which systems are designed using digital models and integrated data. The digital engineering vision for DOME utilizes a model-based systems engineering (MBSE) approach. The system architecture, physical components, control logic, and verification experiments are all designed using MathWorks MATLAB and Simulink. This hierarchical model can combine data from multiple sources at various levels of abstraction. It can be used to simulate the facility’s operations and to test the system using different sets of parameters. Its capabilities can be expanded by interfacing it with high-fidelity multi-physics models, risk analysis tools, etc. The same model can evolve into a digital twin that can monitor operations and conduct predictive analysis using real-time sensor data from the facility. The eventual goal of this effort is to transform the end-to-end engineering of nuclear facilities in every phase of their lifecycle, including design, deployment, and operations.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

NASA NTRS2005

The systems engineering upgrade intiative at NASA's Jet Propulsion Laboratory

JPL is implementing an initiative to significantly upgrade our systems engineering capabilities. This Systems Engineering Upgrade Initiative [SUI] has been authorized by the highest level technical management body of JPL and is sponsored with internal funds. The SUI objective is to upgrade system engineering at JPL to a level that is world class, professional and efficient compared to the FY04/05 baseline. JPL system engineering, along with the other engineering disciplines, is intended to support optimum designs; controlled and efficient implementations; and high quality, reliable, cost effective products. SUI technical activities are categorized into those dealing with people, process and tools. The purpose of this paper is to describe the rationale, objectives/plans and current status of the JPL SUI.

Systems Engineering Upgrade Initiative (SUI)↗

NASA NTRS2017

Preliminary Evaluation of Altitude Scaling for Turbofan Engine Ice Crystal Icing

Preliminary evaluation of altitude scaling for turbofan engine ice crystal icing simulation was conducted during the 2015 LF11 engine icing test campaign in PSL.The results showed that a simplified approach for altitude scaling to simulate the key reference engine ice growth feature and associated icing effects to the engine is possible. But special considerations are needed to address the facility operation limitation for lower altitude engine icing simulation.

altitude scaling↗

NASA NTRS2017

Preliminary Evaluation of Altitude Scaling for Turbofan Engine Ice Crystal Icing

engine ice crystal icing↗

DOE OSTI2024

On the Application of Cyber-Informed Engineering (CIE)

The 2023 National Cybersecurity Strategy has recommended a transition to secure-by-design methodologies in critical infrastructure. This paper presents the adoption of the National Cyber-Informed Engineering (CIE) Strategy as initiated by the U.S. DOE’s CESER office, advocating for the integration of cybersecurity at the earliest stages of system design. The strategy targets design engineers responsible for energy infrastructure to embed CIE principles within the engineering lifecycle, thus enhancing cyber resilience. This paper discusses the expansion of secure-by-design concepts to cyber-physical systems, moving beyond traditional IT security to include engineering considerations that can mitigate cyber risks through design choices. The paper introduces Digital Risk Management, balancing traditional cybersecurity with CIE to reduce both likelihood and impact of cyber threats. A set of CIE starter questions derived from 12 core principles is detailed, aiding engineers to consider cybersecurity in their designs and highlights the importance of CIE in anticipating and reducing the impacts of cyber attacks, suggesting that such integration is essential for national security and infrastructure resilience.

42 ENGINEERING↗

DOE OSTI2024

Opportunities and Challenges for Machine Learning-Assisted Enzyme Engineering

Enzymes can be engineered at the level of their amino acid sequences to optimize key properties such as expression, stability, substrate range, and catalytic efficiency or even to unlock new catalytic activities not found in nature. Because the search space of possible proteins is vast, enzyme engineering usually involves discovering an enzyme starting point that has some level of the desired activity followed by directed evolution to improve its “fitness” for a desired application. Recently, machine learning (ML) has emerged as a powerful tool to complement this empirical process. ML models can contribute to (1) starting point discovery by functional annotation of known protein sequences or generating novel protein sequences with desired functions and (2) navigating protein fitness landscapes for fitness optimization by learning mappings between protein sequences and their associated fitness values. In this Outlook, we explain how ML complements enzyme engineering and discuss its future potential to unlock improved engineering outcomes.

60 APPLIED LIFE SCIENCES↗

NASA NTRSDate not supplied

Exploration of the Versatile Electrically Augmented Turbine Engine Gearbox Concept

Integration of electric machines with the shafts of gas turbine engines is implied in various electrified aircraft propulsion concepts. This includes implementation of the Turbine Electrified Energy Management (TEEM) concept, a motivator for the Versatile Electrically Augmented Turbine Engine (VEATE) gearbox. The VEATE gearbox is a mechanical power transmission concept that seeks to interface electric machines with a gas turbine engine in a synergistic manner. It enables a hybrid electro-mechanical approach for managing power in a gas turbine engine. It is hypothesized that the mechanical design of the VEATE gearbox could be leveraged to enhance the versatility of the present electrical hardware. The VEATE gearbox concept is first introduced and applied to an electrified two-spool advanced geared turbofan meant for powering a single-aisle commercial aircraft. A modeling approach for the gearbox is presented and studies are conducted to investigate the potential application to TEEM and power extraction. There is evidence that the VEATE gearbox could help to reduce the size of the TEEM power system, provide flexibility in power extraction implementation, and exhibit fail-safe design attributes.

Electrified Aircraft Propulsion↗

DOE OSTI2023

Using Cyber-Informed Engineering for Cyber Defense Workbook

This workbook was prepared for a detailed workshop in Cyber-Informed Engineering. It is designed to provide an audience of electrical cooperative engineering staff with an opportunity to practice leveraging the principles of Cyber-Informed Engineering for a hypothetical system upgrade. This workbook contains material describing the fictional project, information about Cyber-Informed Engineering, hands-on exercises, and a copy of the slides presented during the workshop. It can stand alone as a CIE resource.

42 ENGINEERING↗

DOE OSTI2024

Cyber-Enabled Sabotage, Critical Function Assurance, and Cyber-Informed Engineering

Cyber-enabled Sabotage, Critical Function Assurance, and Cyber-Informed Engineering: This discussion will introduce the idea of cyber-enabled sabotage, and the role engineering plays in the cyber defense of critical functions with a focus on electric power systems. It will outline how and why engineering practice must be used to apply cybersecurity principles to establish safe and reliable operations even in the face of determined and skilled adversaries, and give an overview of INL’s Consequence-Driven Cyber-Informed Engineering methodology to apply these principles. There will be an opportunity for audience questions and answers at the end of the session.

42 ENGINEERING↗