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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 181 records · Page 10

Cyber-Informed Engineering: Incorporating CIE into Engineering Curricula

Cyber-Informed Engineering (CIE) is an engineering approach that mitigates the consequences of cyber risk to critical infrastructure by integrating engineered controls into system design and operation. CIE-focused education is necessary to prepare future engineers and technicians to understand and mitigate digital risk in modern engineered systems. This session explores how universities can incorporate CIE into their curricula, provides examples of how existing universities are already leveraging CIE in their programs, and highlights resources to support adoption.

99 - GENERAL AND MISCELLANEOUS↗

Cyber-Informed Engineering Adoption in University Engineering Programs: An Overview of CIE Integration Successes at Nine U.S. Educational Institutions

This report examines the adoption of Cyber-Informed Engineering (CIE) in university engineering programs, driven by the need to protect critical energy infrastructure from adversarial threats. CIE equips current and future engineers and technicians with the necessary mindset, skills, and competencies to enhance the resilience of engineered systems against cyber attacks. This report highlights nine academic partners who are incorporating CIE into their curricula through various approaches, including lectures, courses, and certificates.

42 ENGINEERING↗

Perfect quantum state engineering by the combination of the counterdiabatic driving and the reverse-engineering technique

We propose a method to design shortcuts to adiabaticity for implementing perfect quantum state engineering by the combination of the counterdiabatic driving and the reverse engineering technique. Based on the method, we can design simple schemes to realize the intended dynamics. For the sake of clearness, we apply this method to several examples including two-level, three-level and four-level system. We show that fast quantum state engineering can be realized by utilizing simply-designed auxiliary Hamiltonian. Furthermore, a suitable choice of the control parameters can eliminate the additional couplings in the introduced auxiliary Hamiltonian. Numerical simulation reveals that the constructed scheme is reliable and robust against various dissipation effects and the fluctuations of control parameters in current technology. - Highlights: • Fast and feasible quantum state engineering can be realized by using the method. • The method allows one to control accurately the evolution of the system. • The scheme is fast and robust against dissipation effects and parameter errors. • The scheme can be generalized to realize N-dimensional quantum state engineering.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Chemical kinetics of octane sensitivity in a spark-ignition engine (Chemical Kinetics of Octane Sensitivity in a Spark Ignition Engine)

This article uses a chemical kinetic modeling approach to study the influences of fuel molecular structure on Octane Sensitivity (OS) in Spark Ignition (SI) engines. Octane Sensitivity has the potential to identify fuels that can be used in next-generation high compression, turbocharged SI engines to avoid unwanted knocking conditions and extend the range of operating conditions that can be used in such engines. While the concept of octane numbers of different fuels has been familiar for many years, the variations of their values and their role in determining Octane Sensitivity have not been addressed previously in terms of the basic structures of the fuel molecules. In particular, the importance of electron delocalization on low temperature hydrocarbon reactivity and its role in determining OS in engine fuel is described here for the first time. Finally, the role of electron delocalization on fuel reactivity and Octane Sensitivity is illustrated for a very wide range of engine fuel types, including n-alkane, 1-olefin, n-alcohol, and n-alkyl benzenes, and the unifying features of these fuels and their common trends, using existing detailed chemical kinetic reaction mechanisms that have been collected and unified to produce an overall model with unprecedented capabilities.

30 DIRECT ENERGY CONVERSION↗

Master of Engineering Energy Systems Engineering Program: Smart Campus Energy Systems Demonstration DE-SC0005523

Program Purpose and Position: The mission of the Master of Engineering in Energy Systems Engineering program is to invigorate the pipeline of new engineering graduates interested in energy oriented careers and thus produce a new generation of technical leaders for the energy and power industries. Over the next decade, nearly 50% of the skilled workers and technical leaders in the gas and electric utility industries will retire -- a much larger void than the current available and qualified professionals could fill [CEWD, 2012 survey]. The Masters of Engineering in Energy System Engineering program provides an opportunity for cross-discipline education for graduates interested in a career in the energy industry. It focuses on electric power and the challenges and opportunities to develop a sustainable, reliable and resilient system that meets human needs in an increasingly sustainable manner through the use of environmentally sound energy resources and delivery. Both graduates and employers benefit from a well-trained professional workforce that is ready to hit the road running and be immediately productive in meeting these challenges, through this innovative and unique program.

Dodge, Martha↗

Insights into Engine Knock: Comparisons of Knock Metrics across Ranges of Intake Temperature and Pressure in the CFR Engine

Of late there has been a resurgence in studies investigating parameters that quantify combustion knock in both standardized platforms and modern spark-ignition engines. However, it is still unclear how metrics such as knock (octane) rating, knock onset, and knock intensity are related and how fuels behave according to these metrics across a range of conditions. As part of an ongoing study, the air supply system of a standard Cooperative Fuel Research (CFR) F1/F2 engine was modified to allow mild levels of intake air boosting while staying true to its intended purpose of being the standard device for American Society for Testing and Materials (ASTM)-specified knock rating or octane number tests. For instance, the carburation system and intake air heating manifold are not altered, but the engine was equipped with cylinder pressure transducers to enable both logging of the standard knockmeter readout and state-of-the-art indicated data. For this study, the engine was operated using primary reference fuel 90 (PRF90) at 600 rpm, first following the procedures of the ASTM D2699 research octane number test protocol in order to define the geometric compression ratio set point for standard knock number. Thereafter, compression ratio sweeps were conducted at intake temperatures ranging from 30 to 150°C and intake air boost extending from 0 to 0.3 bar above ambient. The resulting operating map provided a broad envelope of compressed in-cylinder conditions relevant to modern spark-ignition engines. Detailed analysis of the indicated data highlighted a poor correlation between established knock intensity metrics and the knockmeter reading, which is used to characterize a fuel’s octane number. It was further found that the auto-ignition characteristics of PRF90 could be perturbed by means of intake air boosting and heating without being captured by the knockmeter reading.

Rockstroh, Toby↗

Quiet engine program flight engine design study

The results are presented of a preliminary flight engine design study based on the Quiet Engine Program high-bypass, low-noise turbofan engines. Engine configurations, weight, noise characteristics, and performance over a range of flight conditions typical of a subsonic transport aircraft were considered. High and low tip speed engines in various acoustically treated nacelle configurations were included.

Klapproth, J. F.↗

Study of small turbofan engines applicable to single-engine light airplanes

The design, efficiency and cost factors are investigated for application of turbofan propulsion engines to single engine, general aviation light airplanes. A companion study of a hypothetical engine family of a thrust range suitable to such aircraft and having a high degree of commonality of design features and parts is presented. Future turbofan powered light airplanes can have a lower fuel consumption, lower weight, reduced airframe maintenance requirements and improved engine overhaul periods as compared to current piston engined powered airplanes. Achievement of compliance with noise and chemical emission regulations is expected without impairing performance, operating cost or safety.

Merrill, G. L.↗

Aero-acoustic performance comparison of core engine noise suppressors on NASA quiet engine C

The relative aero-acoustic effectiveness of two core engine suppressors, a contractor-designed suppressor delivered with the Quiet Engine, and a NASA-designed suppressor was evaluated. The NASA suppressor was tested with and without a splitter making a total of three configurations being reported in addition to the baseline hardwall case. The aerodynamic results are presented in terms of tailpipe pressure loss, corrected net thrust, and corrected specific fuel consumption as functions of engine power setting. The acoustic results are divided into duct and far-field acoustic data. The NASA-designed core suppressor did the better job of suppressing aft end noise, but the splitter associated with it caused a significant engine performance penality. The NASA core suppressor without the spltter suppressed most of the core noise without any engine performance penalty.

Bloomer, H. E.↗

Aero-acoustic performance comparison of core engine noise suppressors on NASA quiet engine 'C'

The purpose of the experimental program reported herein was to evaluate and compare the relative aero-acoustic effectiveness of two core engine suppressors, a contractor-designed suppressor delivered with the Quiet Engine, and a NASA-designed suppressor, designed and built subsequently. The NASA suppressor was tested with and without a splitter making a total of three configurations being reported in addition to the baseline hardwall case. The aerodynamic results are presented in terms of tailpipe pressure loss, corrected net thrust, and corrected specific fuel consumption as functions of engine power setting. The acoustic results are divided into duct and far-field acoustic data. The NASA-designed core suppressor did the better job of suppressing aft end noise, but the splitter associated with it caused a significant engine performance penalty. The NASA core suppressor without the splitter suppressed most of the core noise without any engine performance penalty.

Bloomer, H. E.↗

Definition study for variable cycle engine testbed engine and associated test program

The product/study double bypass variable cycle engine (VCE) was updated to incorporate recent improvements. The effect of these improvements on mission range and noise levels was determined. This engine design was then compared with current existing high-technology core engines in order to define a subscale testbed configuration that simulated many of the critical technology features of the product/study VCE. Detailed preliminary program plans were then developed for the design, fabrication, and static test of the selected testbed engine configuration. These plans included estimated costs and schedules for the detail design, fabrication and test of the testbed engine and the definition of a test program, test plan, schedule, instrumentation, and test stand requirements.

Vdoviak, J. W.↗

Performance deterioration based on in-service engine data: JT9D jet engine diagnostics program

Results of analyses of engine performance deterioration trends and levels with respect to service usage are presented. Thirty-two JT9D-7A engines were selected for this purpose. The selection of this engine fleet provided the opportunity of obtaining engine performance data starting before the first flight through initial service such that the trend and levels of engine deterioration related to both short and long term deterioration could be more carefully defined. The performance data collected and analyzed included in-flight, on wing (ground), and test stand prerepair and postrepair performance calibrations with expanded instrumentation where feasible. The results of the analyses of these data were used to: (1) close gaps in previously obtained historical data as well as augment the historical data with more carefully obtained data; (2) refine preliminary models of performance deterioration with respect to usage; (3) establish an understanding of the relationships between ground and altitude performance deterioration trends; (4) refine preliminary recommendations concerning means to reduce and control deterioration; and (5) identify areas where additional effort is required to develop an understanding of complex deterioration issues.

Sallee, G. P.↗

Data engineering systems: Computerized modeling and data bank capabilities for engineering analysis

The Data Engineering System (DES) is a computer-based system that organizes technical data and provides automated mechanisms for storage, retrieval, and engineering analysis. The DES combines the benefits of a structured data base system with automated links to large-scale analysis codes. While the DES provides the user with many of the capabilities of a computer-aided design (CAD) system, the systems are actually quite different in several respects. A typical CAD system emphasizes interactive graphics capabilities and organizes data in a manner that optimizes these graphics. On the other hand, the DES is a computer-aided engineering system intended for the engineer who must operationally understand an existing or planned design or who desires to carry out additional technical analysis based on a particular design. The DES emphasizes data retrieval in a form that not only provides the engineer access to search and display the data but also links the data automatically with the computer analysis codes.

Kopp, H.↗

LEADER - An integrated engine behavior and design analyses based real-time fault diagnostic expert system for Space Shuttle Main Engine (SSME)

The LEADER expert system has been developed for automatic learning tasks encompassing real-time detection, identification, verification, and correction of anomalous propulsion system operations, using a set of sensors to monitor engine component performance to ascertain anomalies in engine dynamics and behavior. Two diagnostic approaches are embodied in LEADER's architecture: (1) learning and identifying engine behavior patterns to generate novel hypotheses about possible abnormalities, and (2) the direction of engine sensor data processing to perform resoning based on engine design and functional knowledge, as well as the principles of the relevant mechanics and physics.

Gupta, U. K.↗

Status report on a real time Engine Diagnostics Console for rocket engine exhaust plume monitoring

This paper describes the work done on the Engine Diagnostics Console during the past year of development at Stennis Space Center. The Engine Diagnostics Console (EDC) is a hardware and software package which provides near real time monitoring of rocket engine exhaust plume emissions during ground testing. The long range goal of the EDC development program is to develop an instrument that can detect engine degradation leading to catastrophic failure, and respond by taking preventative measures. The immediate goal for the past year's effort is the ability to process spectral data, taken from a rocket engine's exhaust plume, and to identify in an automated and high speed manner, the elemental species and multielemental materials that are present in the exhaust plume.

Bircher, F. E.↗

Combustion time in the engine cylinder and its effect on engine performance

As part of a general program to study combustion in the engine cylinder and to correlate the phenomena of combustion with the observed performance of actual engines, this paper presents a sketchy outline of what may happen in the engine cylinder during the burning of a charge. It also suggests the type of information needed to supply the details of the picture and points out how combustion time and rate affect the performance of the engine. A theoretical concept of a flame front which is assumed to advance radially from the point of ignition is presented, and calculations based on the area and velocity of this flame and the density of the unburned gases are made to determine the mass rate of combustion. From this rate the mass which has been burned and the pressure at any instant during combustion are computed. This process is then reversed in an effort to determine actual rates of combustion and flame velocities from the pressures as recorded on indicator diagrams. The effects of different rates of combustion on engine performance are then discussed and the importance of proper spark advance is emphasized.

Marvin, Charles F , Jr↗

Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions

Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures. The cooling air temperature was varied from approximately 80 degrees F. to 230 degrees F. and the carburetor-air temperature from approximately 40 degrees F. to 160 degrees F. Tests were made over a large range of engine speeds, brake mean effective pressures, and pressure drops across the cylinder. The correction factors obtained experimentally are compared with those obtained from the semiempirical equations and a fair agreement is noted.

Schey, Oscar W↗