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Viewing 211 to 240 of 21013
2014-09-16
Technical Paper
2014-01-2189
Andrew Slippey, Michael Ellis, Bruce Conway, Hyo Chang Yun
Abstract Carbon fiber reinforced polymer (CFRP) composite material is an attractive structural material in applications where mass is critical. The carbon fiber matrix provides strength comparable to steel with only 25% of the density. The CFRP sheet can often also be made thinner than metal with similar mechanical properties, further increasing the mass savings. However, thermal challenges have arisen with the increased use of composites. In the area of electronics enclosures, traditional metal structures conduct and spread heat over large surfaces, but composites act as insulation. Heat generated by components causes internal temperatures to rise and has detrimental impact on the performance and reliability of the electronics. A method is proposed and tested that utilizes constant conductance heat pipes (CCHPs) that penetrate through the CFRP walls. The CCHPs are capable of transporting significant heat energy through a limited cross-section with a minimal temperature penalty. CCHPs are passive, two-phase, thermal transport devices which have extremely high effective thermal conductivities on the order of thousands of W/m-K.
2014-09-16
Technical Paper
2014-01-2188
Riko Bornholdt, Frank Thielecke
Abstract Due to a shift of the major aviation concerns to focus on enhancements of the successful programs instead of pushing their successors, the need for new methodologies for aircraft system architecture design emerges. Challenging the existing requirements and reconsidering the functions and their allocation could help to dissolve the system specific development paradigm and lead to beneficial architecture concepts. To help understand the mechanisms and boundary conditions of developing fault-tolerant systems, the first part of the paper gives an overview of the successive process of architecture design. The significant architectural design decisions and the concurrent safety assessment process are discussed. One crucial step in the design space exploration of future aircraft system architectures is the allocation of the consumers to the available power sources. Within the paper a methodology for the optimization of the power allocation for flight control systems is proposed. With this methodology the evaluation of a large amount of architecture permutations on the basis of a preliminary system safety assessment regarding multiple top failure events is possible in a short time period.
2014-09-16
Technical Paper
2014-01-2169
Yves C.J. Lemmens, Tuur Benoit, Rob De Roo, Jon Verbeke
Vives College University and Kulab (KU Leuven University campus Ostend) in Belgium are undertaking an aeronautical research program about the development of a new Unmanned Aerial Vehicle (UAV). Since the UAV is completely electrically powered, the analysis of the energy management of the integrated electrical system was critical to the development of the UAV. LMS, A Siemens Business, is involved in the project to support the development of a multi-physics simulation model for electro-thermal analysis of the aircraft. This paper reports on the subsequent investigation of integrating the detailed electrical system model for a Pilot-in-the-Loop simulation. In order to perform this simulation, the model of the electrical system was converted into a real-time simulation model. The aim was to perform more realistic flight simulations to evaluate the performance of the aircraft before its first flight by taking into account the electrical system's behavior. Furthermore, the behavior of the electrical system can be directly assessed during and after the Pilot-in-the-Loop tests.
2014-09-16
Technical Paper
2014-01-2174
Nicholas Ernest, Kelly Cohen, Corey Schumacher, David Casbeer
Abstract Looking forward to an autonomous Unmanned Combat Aerial Vehicle (UCAV) for future applications, it becomes apparent that on-board intelligent controllers will be necessary for these advanced systems. LETHA (Learning Enhanced Tactical Handling Algorithm) was created to develop intelligent managers for these advanced unmanned craft through the novel means of a genetic cascading fuzzy system. In this approach, a genetic algorithm creates rule bases and optimizes membership functions for multiple fuzzy logic systems, whose inputs and outputs feed into one another alongside crisp data. A simulation space referred to as HADES (Hoplological Autonomous Defend and Engage Simulation) was created in which LETHA can train the UCAVs intelligent controllers. Equipped with advanced sensors, a limited supply of Self-Defense Missiles (SDM), and a recharging Laser Weapon System (LWS), these UCAVs can navigate a pre-defined route through the mission space, counter enemy threats, and destroy mission-critical targets.
2014-09-16
Technical Paper
2014-01-2176
Niloofar Rashidi Mehrabadi, Bo Wen, Rolando Burgos, Dushan Boroyevich, Chris Roy
Abstract The development of the concepts, terminology and methodology of verification and validation is based on practical issues, not the philosophy of science. Different communities have tried to improve the existing terminology to one which is more comprehensible in their own field of study. All definitions follow the same concept, but they have been defined in a way to be most applicable to a specific field of study. This paper proposes the Verification, Validation, and Uncertainty Quantification (VV&UQ) framework applicable to power electronic systems. Although the steps are similar to the VV&UQ frameworks' steps from other societies, this framework is more efficient as a result of the new arrangement of the steps which makes this procedure more comprehensible. This new arrangement gives this procedure the capability of improving the model in the most efficient way. Since the main goal of the VV&UQ process is to quantitatively assess the confidence in modeling and simulation, the second part of this paper focuses on uncertainty quantification.
2014-09-16
Technical Paper
2014-01-2173
Aurelie Beaugency, Marc Gatti, Didier Regis
Abstract Since 2000, avionics is facing several changes, mostly driven by technological improvements in the electronics industry and innovation requirements from aircraft manufacturers. First, it has progressively lost its technological leadership over innovation processes. Second, the explosion of the electronics consumer industry has contributed to shorten even more its technology life cycles, and promoted the use of COTS. Third, the increasing complexity of avionics systems, which integrate more and more functions, have encouraged new players to enter the market. The aim of this article is to analyze how technological changes can affect the competitiveness of avionics firms. We refer to criticality levels as a determinant of the market competitiveness. Certification processes and costs could stop new comers to bring innovations from the consumer electronics industry and protects traditional players. The study will compare three avionics systems regarding their patent dynamics since 1980: flight controls, Integrated Modular avionics and Head-Up Displays.
2014-09-16
Technical Paper
2014-01-2175
Jay Wilhelm, Joseph Close, Wade Huebsch
A Hybrid Projectile (HP) is a ballistically launched round that transforms into an Unmanned Aerial Vehicle (UAV) at a designated point during flight. Aerodynamic control surfaces and associated control laws were sought that would extend the projectile's range using body lift and include guidance for a selected point of impact. Several challenges were encountered during the modification of an existing projectile, in this case a 40mm round, to achieve range extension and controllability. The control surfaces must be designed to allow for de-spin, controllability, and natural static stability. Also, a control system with laws and guidance relationships between heading, pitch or glide rate, and the associated aerodynamic surface movements needed to be developed. The designed aerodynamic surfaces, external ballistics, and control methods developed were modeled in a projectile flight simulator built in MATLAB. The base model was an M781 practice round and the aerodynamic coefficients and mass data were found in literature.
2014-09-16
Technical Paper
2014-01-2129
Vincent Metzger, Douglas Parker, Alain Philippe, Sebastien Claudot
Abstract Fiber optic physical contact connection technology has been used with multimode fiber in civilian aircraft for over 30 years with very good proven reliable performance. The extensive use of singlemode fiber (SMF) in FTTx Telecom market rollouts speeds up the development of passive optical components which significantly decreases the cost, expands capability and increases the reliability level of singlemode components. SMF transmission seems mandatory for future applications even in mil-aero and other harsh environment applications due to increased data rate requirements and new sensors applications. In harsh environment applications, is it realistic to use SMF with cores that are 30 times smaller in area compared to multimode fiber (MMF) when highly exposed to contamination? The present paper presents a technology of beam expansion interconnection that mixes a physical contact (PC) with an expanded optical surface. The optical connector brings together benefits of both technologies resulting in a reliable connection requiring low maintenance for SMF fiber optic applications.
2014-09-16
Technical Paper
2014-01-2127
Karl Strauss
Abstract “Today's electronic components rely on principles of physics and science with no manufacturing precedence and little data on long term stability and reliability.” [1] Yet many are counting on their reliable performance years if not decades into the future, sometimes after being literally abandoned in barns or stored neatly in tightly sealed bags. What makes sense? To toss everything away, or use it as is and hope for the best? Surely there must be a middle ground! With an unprecedented number of missions in its future and an ever-tightening budget, NASA faces the daunting task of doing more with less. One proven way for a project to save money is to use already screened and qualified devices from the spares of its predecessors. But what is the risk in doing so? How can a project reliably count on the value of spare devices if the risk of using them is not, in itself, defined? With hundreds of thousands of devices left over from previous missions, the parts bins of NASA hold a wealth of electronic components, (possibly) ready for use many years after their production.
2014-09-16
Technical Paper
2014-01-2125
Janice Meraglia, Mitchell Miller
Abstract Counterfeit items can be viewed as the by-product of a supply chain which has been compromised. While many industries are impacted, certain types of products can mean the difference between life and death. Electronics are of special interest, however, mechanical parts can also have dire consequences. The point is that the counterfeiting community is very diverse. The business model is fluid and unrestricted. Electronics today…hardware tomorrow. All of this leads to the need for an authentication platform that is agnostic to product. Most supply chains would benefit from a technical way to have assurance of authenticity - a benefit that could be shared by all. A comprehensive marking program, such as SigNature DNA, offers value to all supply chain participants as outlined below: Manufacturers will have the ability to effectively monitor their legacy components Authorized distributors will have an absolute way to verify and accept returns Defense contractors and agencies will have forensically authentic and traceable inventory at their disposal End users will have the power to authenticate stock to the component level
2014-09-16
Technical Paper
2014-01-2117
Michael L. Zierolf, Thomas Brinson, Andrew Fleming
Abstract Recent emphasis on optimization of engine technologies with ancillary subsystems such as power and thermal management has created a need for integrated system modeling. These systems are coupled such that federated design methods may not lead to the most synergetic solution. Obtaining an optimal design is often contingent on developing an integrated model. Integrated models, however, can involve combining complex simulation platforms into a single system of systems, which can present many challenges. Model organization and configuration control become increasingly important when orchestrating various models into a single simulation. Additionally, it is important to understand such details as the interface between models and signal routing to ensure the integrated behavior is not contaminated or biased. This paper will present some key learnings for model integration to help alleviate some of the challenges with system-based modeling.
2014-09-16
Technical Paper
2014-01-2150
Martin Bradish, Obed Sands, Ted Wright, Casey Bakula, Daniel Oldham, William Ivancic, Michael Lewis, Joseph Klebau, Nicholas Tollis, Andrew Jalics
Abstract This paper summarizes the Power, Avionics and Software (PAS) 1.0 subsystem integration testing and test results that occurred in August and September of 2013. This paper covers the capabilities of each PAS assembly to meet integration test objectives for non-safety critical, non-flight, non-human-rated hardware and software development. This test report is the outcome of the first integration of the PAS subsystem and is meant to provide data for subsequent designs, development and testing of the future PAS subsystems. The two main objectives were to assess the ability of the PAS assemblies' to exchange messages and to perform audio tests of both inbound and outbound channels. This paper describes each test performed, defines the test, the data, and provides conclusions and recommendations.
2014-09-16
Technical Paper
2014-01-2148
Jon Hagar
Abstract System testing can, in part, be defined as the application of concepts as an attempt to demonstrate that the implementation does not meet its intended use. Unfortunately, some industry verification test efforts only show that a system meets requirements which while necessary, are not sufficient to fully address a product's system-software testing. Managers, engineers, and testers may not be familiar with the wide variety of test concepts, approaches, and standards available for system-software testing-many of which can save projects money and effort in the long run. Newer software test standards and advanced techniques can offer a wealth of knowledge and improvement opportunities for software products. This paper offers a review of emerging software test concepts and standards in which teams will find potential value toward their improvement efforts including: Math-based techniques which apply combinatorial, statistical, Design of Experiments (DOE), or domain-based concepts Attack-based testing which focuses on common industry error taxonomies Independent model-based testing using tools and standards New standards-driven testing to address verification and validation (V&V), testing, and documentation.
2014-09-16
Technical Paper
2014-01-2146
Rudolf Neydorf, Sergey Novikov, Nikita Kudinov
Abstract Airship designers research application versions of systems with several ballonets for adjustment of airship roll and/or pitch as a whole. This requires effective automatic status management of each separate ballonet. But multi-ballonet system control issue encounters the absence of industrially measurable variables of each separate ballonet status. Thus status control issue of the system becomes uncertain. The fact requires the issue studying and shaping new scientific and technical solutions. This publication represents research results implying that fairly simple implementation and effective result can be achieved by application of fuzzy control concept. Its application is built on generating the representative quantity of fuzzy production rules. They are based on present set evaluation of known parameters and measured variables. This results in fuzzy but meaningful image of ballonet system status and airship as a whole. Thus achieving fairly good control over multi-ballonet system.
2014-09-16
Technical Paper
2014-01-2139
Serhiy Bozhko, Seang Shen Yeoh, Fei Gao, Tao Yang, Christopher Hill
Abstract The paper reports the control design for an aircraft electric starter-generator system based-on high-speed permanent magnet machine operated in a flux-weakening mode and controlled by an active front-end rectifier. The proposed system utilizes advances of modern power electronics allowing the use of novel machine types and the introduction of controlled power electronics into the main path of energy flow. The paper focuses on control design for such system and includes development of flux weakening control of high-speed permanent magnet machine and droop control of the system output dc-link current. The achieved analytical design results and the expected system performance are confirmed by time-domain simulations.
2014-09-16
Technical Paper
2014-01-2113
Fei Gao, Serhiy Bozhko, Greg Asher
Abstract Stability is a great concern for the Electrical Power System (EPS) in the More Electric Aircraft (MEA). It is known that tightly controlled power electronic converters and motor drives may behave as constant power loads (CPLs) which may produce oscillations and cause instability. The paper investigates the stability boundaries for dc multi-source EPS under different power sharing strategies. For each possible strategy the corresponding reduced-order models are derived. The impedance criterion is then applied to study the EPS stability margins and investigates how these margins are influenced by different parameters, such as main bus capacitance, generator/converter control dynamics, cabling arrangements etc. These results are also illustrated by the root contours of reduced-order EPS models. Theoretical results achieved in the paper are confirmed by the time-domain simulations.
2014-09-16
Technical Paper
2014-01-2115
Brian C. Raczkowski, Benjamin Loop, Jason Wells, Eric Walters, Oleg Wasynczuk, Sean Field, Jason Gousy
Abstract Future more electric aircraft (MEA) architectures that improve electrical power system's (EPS's) source and load utilization will require advance stability analysis capabilities. Systems are becoming more complex with bidirectional flows from power regeneration, multiple sources per channel and higher peak to average power ratios. Unknown load profiles with large transients complicate common stability analysis techniques. Advancements in analysis are critical for providing useful feedback to the system integrator and designers of multi-source, multi-load power systems. Overall, a framework for evaluating stability with large displacement events has been developed. Within this framework, voltage transient bounds are obtained by identifying the worst case load profile. The results can be used by system designers or integrators to provide specifications or limits to suppliers. Subsystem suppliers can test and evaluate their design prior to integration and hardware development. By identifying concerns during the design phase, a more streamlined approach to hardware development can save on rework, integration delays and cost.
2014-09-16
Technical Paper
2014-01-2111
Shweta Sanjeev, Goutham Selvaraj, Patrick Franks, Kaushik Rajashekara
Abstract The transition towards More Electric Aircraft (MEA) architectures has challenges relating to integration of power electronics with the starter generator system for on-engine application. To efficiently operate the power electronics in the hostile engine environment at high switching frequency and for better thermal management, use of silicon carbide (SiC) power devices for a bi-directional power converter is examined. In this paper, development of a 50 kVA bi-directional converter operating at an ambient temperature of about 2000C is presented. The design and operation of the converter with details of control algorithm implementation and cooling chamber design are also discussed.
2014-09-16
Technical Paper
2014-01-2101
Joseph Dygert, Melissa Morris, Patrick Browning
Abstract The high demand for traditional air traffic as well as increased use of unmanned aerial systems (UAS) has resulted in researchers examining alternative technologies which would result in safer, more reliable, and better performing aircraft. Active methods of aerodynamic flow control may be the most promising approach to this problem. Research in the area of aerodynamic control is transitioning from traditional mechanical flow control devices to, among other methods, plasma actuators. Plasma actuators offer an inexpensive and energy efficient method of flow control. Dielectric Barrier Discharge (DBD), one of the most widely studied forms of plasma actuation, employs an electrohydrodynamic (EHD) device which uses dominant electric fields for actuation. Unlike traditional flow control methods, a DBD device operates without moving components or mass injection methods. Publications discussing the optimization of DBD flow control versus a single variable such as gap width, voltage, dielectric constant, etc., have been widely published, and instigated a 2003 paper published by the IEEE-DEIS-EHD Technical Committee titled “Recommended International Standard for Dimensionless Parameters Used in Electrohydrodynamics.”
2014-09-16
Technical Paper
2014-01-2267
George Nicholas Bullen
Abstract Rapid advances in cloud-based computing, robotics and smart sensors, multi-modal modeling and simulation, and advanced production are transforming modern manufacturing. The shift toward smaller runs on custom-designed products favors agile and adaptable workplaces that can compete in the global economy. This paper and presentation will describe the advances in Digital Manufacturing that provides the backbone to tighten integration and interoperability of design methods interlinked with advanced manufacturing technologies and agile business practices. The digital tapestry that seamlessly connects computer design tools, modeling and simulation, intelligent machines and sensors, additive manufacturing, manufacturing methods, and post-delivery services to shorten the time and cost between idea generation and first successful product-in-hand will be illustrated.
2014-09-16
Technical Paper
2014-01-2201
Fan Frank Wang
Abstract This article is about the issues associated with the published thermal data from commercial off the shelf (COTS) component manufacturers. Some of the published electrical component thermal data can be confusing and/or misleading. This article discusses the possibility of wrong design decisions that can be made using published COTS thermal data. There are two major issues of the published thermal data associated with the use of COTS components. One is the published ambient temperature rating. Another is the published thermal resistance. This paper will discuss these two major issues in details and provide mitigation suggestions.
2014-09-16
Technical Paper
2014-01-2104
Jon Zumberge, John Mersch
Cost and performance requirements are driving military and commercial systems to highly integrated, optimized systems which require more sophisticated, highly complex controls. To realize benefits and make confident decisions, the validation of both plant and control models becomes critical. To quickly develop controls for these systems, it is beneficial to develop models and determine the uncertainty of those models so as to predict performance and stability. A process of model validation for a boost circuit based on acceptance sampling is presented here. The validation process described in this paper includes the steps of defining requirements, performing a screening and exploration of the system, completing a system and parameter identification, and finally executing a validation test. To minimize the cost of experimentation and simulation, design of experiments is used extensively to limit the amount of data taken without losing information. One key contribution in this paper is the use of tolerance intervals as an estimation of model accuracy.
2014-09-16
Technical Paper
2014-01-2128
Ephraim Suhir, Alain Bensoussan
Abstract The attributes of and challenges in the recently suggested probabilistic design for reliability (PDfR) concept, and the role of its major constituents - failure oriented accelerated testing (FOAT) and physically meaningful predictive modeling (PM) - are addressed, advanced and discussed. The emphasis is on the application of the powerful and flexible Boltzmann-Arrhenius-Zhurkov (BAZ) model, and particularly on its multi-parametric aspect. The model can be effectively used to analyze and design optoelectronic (OE) devices and systems with the predicted, quantified, assured, and, if appropriate and cost-effective, even maintained probability of failure in the field. The numerical example is carried out for an OE system subjected to the combined action of the ionizing radiation and elevated voltage as the major stimuli (stressors). The measured leakage current is used as a suitable characteristic of the degree of degradation. It is concluded that the suggested methodology can be accepted as an effective means for the evaluation of the operational reliability of the aerospace electronics and OE systems and that the next generation of qualification testing (QT) specifications and best practices for such systems could be viewed and conducted as a “quasi-FOAT,” a sort of an “initial stage of FOAT” that adequately replicates the initial non-destructive segment of the previously conducted comprehensive “full-scale” FOAT.
2014-09-16
Technical Paper
2014-01-2122
Fidele Moupfouma, Amadou Ndoye, Mohsen Jalali, William Tse
Abstract Advanced commercial aircraft increasingly use more composite or hybrid (metal and composite) materials in structural elements and, despite technological challenges to be overcome, composites remain the future of the aviation industry. Composite and hybrid aircraft today are equipped with digital systems such as fly by wire for reliable operations no matter what the flying environment is. These systems are however very sensitive to electromagnetic energy. During flight, aircraft can face High Intensity Radiated Fields (HIRF), static electricity, or lightning. The coupling of any of these threats with airframe structure induces electromagnetic energy that can impair the operation of avionics and navigation systems. This paper focuses on systems susceptibility in composite aircraft and concludes that the same electromagnetic rules dedicated to all metal aircraft for systems and wiring integration cannot be applied directly as such for composite aircraft.
2014-09-16
Technical Paper
2014-01-2123
Andre Hessling
Abstract Advanced technologies in LED's have the potential to reduce maintenance and improve aircraft safety. Aircrafts need adequate illumination for night time landing. New technology such as high-power LEDs allow for better suited light distributions, more whitish light compatible for mesopic lighting conditions and reduced glare in adverse weather conditions. LEDs and the associated electronics are more susceptible to harsh environmental conditions and this needs to be accounted for in the design of the equipment. Highly conductive metal core PCBs (MCPCB) allow for adequate cooling in a mirror telescopic optical arrangement when coupled with robust active cooling. Closed loop optical feedback of output flux ensures constant performance over the lifetime of the light unit and allows for indication of remaining useful life to the operator to plan maintenance activities. Parylene coating inhibits premature degradation of the LEDs induced by water vapor and corrosive gases.
2014-09-16
Technical Paper
2014-01-2120
Jennifer C. Shaw, Patrick Norman, Stuart Galloway, Graeme Burt
Abstract Radical new electrically propelled aircraft are being considered to meet strict future performance goals. One concept design proposed is a Turboelectric Distributed Propulsion (TeDP) aircraft that utilises a number of electrically driven propulsors. Such concepts place a new and significant reliance on an aircraft's electrical system for safe and efficient flight. Accordingly, in addition to providing certainty that supply reliability targets are being met, a contingency analysis, evaluating the probability of component failure within the electrical network and the impact of that failure upon the available thrust must also be undertaken for architecture designs. Solutions that meet specified thrust requirements at a minimum associated weight are desired as these will likely achieve the greatest performance against the proposed emissions targets. This paper presents a Fault Tree Analysis (FTA) based design approach for the electrical system and thrust reliability analysis of TeDP aircraft architectures.
2014-09-16
Technical Paper
2014-01-2119
Steven David Angus Fletcher, Patrick Norman, Stuart Galloway, Graeme Burt
Abstract The development of the More-Electric Engine (MEE) concept will see an expansion in the power levels, functionality and criticality of electrical systems within engines. However, to date, these more critical electrical systems have not been accounted for in existing engine certification standards. To begin to address this gap, this paper conducts a review of current engine certification standards in order to determine how these standards will impact on the design requirements of More-Electric Engine (MEE) electrical system architectures. The paper focuses on determining two key architectural requirements: the number of individual failures an architecture can accommodate and still remain functional and the rate at which these failures are allowed to occur. The paper concludes by discussing how the derived failure rates begin to define a set of design requirements for MEE electrical architectures, considering various operating strategies, and demonstrates their application to example MEE electrical system architecture designs.
2014-09-16
Technical Paper
2014-01-2217
Javier Gazzarri, Nishant Shrivastava, Robyn Jackey, Craig Borghesani
Abstract Battery Management System (BMS) design is a complex task requiring sophisticated models that mimic the electrochemical behavior of the battery cell under a variety of operating conditions. Equivalent circuits are well-suited for this task because they offer a balance between fidelity and simulation speed, their parameters reflect direct experimental observations, and they are scalable. Scalability is particularly important at the real time simulation stage, where a model of the battery pack runs on a real-time simulator that is physically connected to the peripheral hardware in charge of monitoring and control. With modern battery systems comprising hundreds of cells, it is important to employ a modeling and simulation approach that is capable of handling numerous simultaneous instances of the basic unit cell while maintaining real time performance. In previous publications we presented a technique for the creation of a battery cell model that contains the electrochemical fingerprints of a battery cell based on equivalent circuit model fitting to experimental data.
2014-09-16
Technical Paper
2014-01-2204
Gregory J. Moore, Frank Puglia, Lawrence Myron, Stephen Lasher, Bob Doane, Joe Gnanaraj, Seth Cohen, Arthur Dobley, Ryan Lawrence, Rong Yan
Abstract For 70 years Yardney has been a leader in specialty battery and energy systems for military, space, avionics, weapon systems and undersea vehicles. In addition to battery systems, Yardney also delivers hybrid systems for ground, space, undersea and avionic applications. The beauty of hybrid systems, combining energy sources such as batteries, capacitors, fuel cells and solar, is that they can be used to optimize energy and power density, and with proper design, the systems can also lead to longevity of components and an overall cost savings. For ground applications, utilization of hybrid systems can assist in conservation of fuel by making vehicle applications more efficient. For space applications, satisfying pulses can be improved by a capacitor and battery hybrid energy storage system. To optimize aircraft performance and decrease operating costs, avionics are beginning to move towards more electric aircrafts (MEA). This embraces the concept of utilizing electrical power for driving aircraft subsystems currently powered by mechanical means.
2014-09-16
Technical Paper
2014-01-2170
Michelle Bash, Michael Boyd, Chad Miller
Abstract This paper presents the details of an engine emulation system utilized within a Hardware-in-the-Loop (HIL) test environment for aircraft power systems. The paper focuses on the software and hardware interfaces that enable the coupling of the engine model and the generator hardware. In particular, the rotor dynamics model that provides the critical link between the modeled dynamics of the engine and the measured dynamics of the generator is described in detail. Careful consideration for the measured torque is included since the measurement contains inertial effects as well as torsional resonances. In addition, the rotor model is equipped with the ability to apply power and speed scaling between the engine and generator. This scaling approach provides significant flexibility that can be useful when hardware resources are limited such that a direct engine-generator match is not possible or when one wants to evaluate turboshaft engine dynamics for a variety of applications and power levels.
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