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2014-10-06
Standard
AS5671
This SAE Aerospace Standard (AS) provides design criteria for onboard stairways intended for use by passengers aboard multi-deck transport category airplanes. It is not intended for stairways designed for use only by crewmembers, supernumeries, or maintenance personnel. Additionally, this AS does not apply to fuselage mounted or external stairways used for boarding passengers, which are covered by ARP836. The purpose of this AS is to assist airplane manufacturers in designing stairways on which users will be less likely to experience a misstep or fall during normal operations and on which movement during an emergency evacuation will be as efficient as is possible.
2014-10-01
Magazine
Propulsion: Energy Sources Flying on vegetation Avionics/Electronics Avionics heat up, in a good way Unmanned Vehicles Reaching the benchmark in secure unmanned vehicle software Thermal Management Submersion and directed flow cooling technology for military applications RF & Microwave Technology Airborne antenna considerations for C-Band telemetry systems Software-designed system improves wireless test speed and coverage
2014-09-30
Article
Brose is manufacturing different vehicle mechatronic systems from its recently renovated New Boston, MI, plant.
2014-09-30
Technical Paper
2014-01-2429
C Venkatesan, V Faustino, S Arun, S Ravi Shankar
Abstract The automotive industry needs sustainable seating products which offer good climate performance and superior seating comfort. The safety requirement is always a concern for current seating systems. The life of the present seating system is low and absorbs moisture over a period of time which affects seat performance (cushioning effect). Recycling is one of the major concerns as far as polyurethane (PU) is concerned. This paper presents the development of an alternative material which is eco-friendly and light in weight. Thermoplastic Polyolefin (PO) materials were tried in place PU for many good reasons. It is closed cell foam which has better tear and abrasion resistance. It doesn't absorb water and has excellent weathering resistance. Also it has a better cushioning effect and available in various colours. Because of superior tear resistance, it is possible to eliminate upholstery and would reduce system level cost. The development involves testing and characterization of the materials, making of prototypes and validations.
2014-09-30
Technical Paper
2014-01-2406
Marco Carriglio, Alberto Clarich, Rosario Russo, Enrico Nobile, Paola Ranut
Abstract The main purpose of this study is the development of an innovative methodology for Heat Exchangers (HE) design to replace the conventional design procedures. The new procedure is based on the definition of a software package managed by modeFRONTIER, a multi-objective optimization software produced by ESTECO, able to create HE virtual models by targeting several objectives, like HE performance, optimal use of material, HE minimal weight and size and optimal manufacturability. The proposed methodology consists first in the definition of a workflow for the automatic CFD simulation of a parametric model of a periodic HE cellular element. This is followed by the definition of a Response Surface (meta-model) covering all the possible range of parameters' combination, the definition of a “bridge”, e.g. low-fidelity - standard or macroscopic - models to extend the behavior of the liquid and air HE cellular elements to a real scale HE, and an optimization process to obtain the optimal HE design for any proposed application and requirements.
2014-09-30
Technical Paper
2014-01-2395
Gurunathan Varun Kumar, Meer Reshma Sheerin, Vedachalam Saravana Prabu, Kallikadan Jean, Chaitanya Rajguru, Murugesan Dinesh, Andrew Croft
Abstract Automotive climate control systems are evolving at a rapid pace to meet the overall vehicle requirements and the user expectations for comfort and convenience. This poses a challenge in the product development life cycle of multi-platform vehicle systems with respect to development time and optimal performance in the Heating, Ventilation and Air Conditioning (HVAC) system. This paper proposes rapid HVAC plant model design and development using simplified one-dimensional (1D) simulation models for fast simulations. The specific accuracy limitations of such a simplified model are overcome using limited three-dimensional computational fluid dynamics (3D CFD) modelling. User-level control strategy is developed in an integrated simulation environment that includes a reference 1D model and a control algorithm simulator. The simulation data is used to study and analyse the temperature and airflow distribution in the system. Based on these results, simpler models for the HVAC system are derived.
2014-09-30
Technical Paper
2014-01-2343
Manfei Bai, Gangfeng Tan, Yadong Deng, Wenying Wang, Hui Yan
Abstract To make full use of engine exhaust heat and further improve the utilization of the energy efficiency of the heavy truck, thermoelectric module is used to contribute to thermoelectric power generation. The hot-end temperature of the module varies with the engine operating condition because it is connected with the exhaust pipe. The cold-end of the thermoelectric module is mainly cooled by engine cooling system. Increasing the temperature difference between the hot-end and cold-end of the thermoelectric module is a good way to improve the thermoelectric conversion efficiency. For the poor controllability of the hot-end temperature of the thermoelectric module, this study puts forward by lowering the cold-end temperature of the thermoelectric module so as to ensure the improvement of the thermoelectric conversion efficiency. The cooling circle for the cold-end of the thermoelectric module which is independent of the engine cooling system is built. The nucleate boiling flow is adopted to strengthen the heat transfer from the thermoelectric module cold side to the cooling water.
2014-09-30
Technical Paper
2014-01-2325
Michael Franke, Shirish Bhide, Jack Liang, Michael Neitz, Thomas Hamm
Abstract Exhaust emission reduction and improvements in energy consumption will continuously determine future developments of on-road and off-road engines. Fuel flexibility by substituting Diesel with Natural Gas is becoming increasingly important. To meet these future requirements engines will get more complex. Additional and more advanced accessory systems for waste heat recovery (WHR), gaseous fuel supply, exhaust after-treatment and controls will be added to the base engine. This additional complexity will increase package size, weight and cost of the complete powertrain. Another critical element in future engine development is the optimization of the base engine. Fundamental questions are how much the base engine can contribute to meet the future exhaust emission standards, including CO2 and how much of the incremental size, weight and cost of the additional accessories can be compensated by optimizing the base engine. This paper describes options and potentials to improve the base engine for future commercial and industrial engines.
2014-09-30
Technical Paper
2014-01-2341
Salvador Sermeno, Eric Bideaux, Tessa Morgan, Duc Nguyen
Abstract Vehicle thermal management covers the engineering field of solutions that maintain the complete vehicle in acceptable operating conditions regarding component and fluid temperatures in an engine. The maximum efficiency rating of a Diesel engine reaches up to 45%. In order to improve the fuel efficiency of the vehicle one can reduce the losses generated by the cooling system. Ideally, the full motive force of the engine should be used for propulsion and new and more efficient energy sources have to be explored to power the secondary systems (cooling, compressed air…). This paper introduces a dynamic programming algorithm which is used to determine the maximum gains during operation for a given architecture of the cooling system of a Heavy Duty Truck. The algorithm, based in Bellman principle, will determine the best control trajectory for the pump and the fan according to energetic and control goals (fuel economy, regulation of temperature…). For this purpose, a reduced model of the cooling system based on energy balance equations has been determined and validated through simulations.
2014-09-30
WIP Standard
J2377
This SAE Recommended Practice (RP) provides test procedures for air braked trucks and truck-tractors used to tow single and multiple trailer combinations on highways. This RP is not intended for off-highway applications.
2014-09-26
WIP Standard
AIR4766/2A
This SAE Aerospace Information Report (AIR) provides information on aircraft cabin air quality, including: - Airborne contaminant gases, vapors, and aerosols. - Identified potential sources. - Comfort, health and safety issues. - Airborne chemical measurement. - Regulations and standards. - Operating conditions and equipment that may cause aircraft cabin contamination by airborne chemicals (including Failure Conditions and normal Commercial Practices). - Airborne chemical control systems. It does not deal with airflow requirements.
2014-09-17
WIP Standard
J2670
This SAE standard applies to any and all additives and chemical solutions intended for aftermarket use in the refrigerant circuit of vehicle air-conditioning systems with belt-driven compressors, except as noted below. This standard provides testing and acceptance criteria for determining the stability and compatibility of additives and flushing materials (solutions) with A/C system materials and components, that may be intended for use in servicing or operation of vehicle air conditioning systems. This standard does not provide test criteria for additive, compressor lubricant, or flushing solution effectiveness; such testing is the responsibility of the additive and/or solution manufacturer/supplier. This standard does not cover additives or flushing materials for electrically driven compressors. The use of additives with electrically driven compressors might cause electrical shorting and compressor failure. It is not the intent of this document to identify the requirements for ultraviolet leak detection dyes.
2014-09-17
WIP Standard
J2297
This SAE Standard applies to dyes intended to be introduced into a mobile air-conditioning system refrigerant circuit for the purpose of allowing the application of ultraviolet leak detection. In order to label any product(s) they shall meet SAE J2297, and the certification process as described in SAE J2911 must be followed and the documentation described in the appendix shall be submitted to SAE.
2014-09-16
Technical Paper
2014-01-2202
Gene Tu, Wei Shih, Walter Yuen
Abstract To meet pulse power mode component cooling application needs, we developed, fabricated and tested a concept to use energy storage material and phase change material to enhance the heat dissipation of a conventional heat sink. Test results demonstrated the ESM/PCM heat sink has unique thermal performance. Under the same working condition, the peak temperature of ESM/PCM heat sink is 1.5°C lower than of a conventional heat sink. An optimized design can lead to a significant weight reduction for the heat sink in applications with high peak load and low duty power cycle power.
2014-09-16
Technical Paper
2014-01-2203
Daniel Schlabe, Jens Lienig
Abstract This paper describes a novel Thermal Management Function (TMF) and its design process developed in the framework of the Clean Sky project. This TMF is capable of calculating optimized control signals in real-time for thermal management systems by using model-based system knowledge. This can be either a physical model of the system or a data record generated from this model. The TMF provides control signals to the air and vapor cycle which are possible sources of cooling power, as well as load reduction or shedding signals. To determine an optimal cooling split between air cycle, vapor cycle, and its associated ram air channels, trade factors are being used to make electrical power offtake and ram air usage (i.e. drag) comparable, since both have influence on fuel consumption. An associated development process is being elaborated that enables a fast adaptation of the TMF to new architectures and systems. This will be illustrated by means of a bleedless thermal management architecture.
2014-09-16
Technical Paper
2014-01-2192
Philip Abolmoali, Javier A. Parrilla, Awatef Hamed
Abstract The optimal integration of vehicle subsystems is of critical importance in the design of future energy efficient fighter aircraft. The INVENT (INtegrated Vehicle ENergy Technology) program has been dedicated to this endeavor through modeling/simulation of thermal management, power generation & distribution, & actuation subsystems. Achieving dual cooling & power generation capability from a single subsystem would be consistent with current efforts in system integration optimization. In this paper, we present a reconfiguration of an archetypal closed-loop air cycle system for a modern fighter as an open-loop gas generator cycle operating interchangeably between refrigeration and auxiliary power modes. A numerical model was developed within NPSS to assess maximum power extraction capabilities of a system originally designed for cooling purposes under different operating conditions. Presented results demonstrate variations in maximum power extraction, flow rates, and turbomachinery performance parameters over a range of flight altitudes and Mach numbers.
2014-09-16
Technical Paper
2014-01-2190
Michael Ellis, William Anderson, Jared Montgomery
Under a program funded by the Air Force Research Laboratory (AFRL), Advanced Cooling Technologies, Inc. (ACT) has developed a series of passive thermal management techniques for cooling avionics. Many avionics packages are often exposed to environment temperatures much higher than the maximum allowable temperatures of the electronics. This condition prevents the rejection of waste heat generated by these electronics to the surrounding environment and results in significant ambient heat gain. As a result, heat must be transported to a remote sink. However, sink selection aboard modern aircraft is limited at best. Often, the only viable sink is aircraft fuel and, depending on mission profile, the fuel temperature can become too high to effectively cool avionics. As a result, the electronic components must operate at higher than intended temperatures during portions of the mission profile, which reduces component lifetime and significantly increases the probability of failure. To address this issue, ACT developed two passive thermal management approaches for avionics packages: heat pipe assemblies to reduce the internal temperature gradient and a Loop Heat Pipe (LHP) to transport thermal energy to alternative sinks.
2014-09-16
Technical Paper
2014-01-2191
Mark Donovan, Pedro Del valle
As aviation enters the future, new technologies and philosophies are required to keep up with ever changing demands and increased market competition. Aircraft designers are required to come up with new and innovative ways to optimise systems and improve efficiencies. Onboard thermal management is an area that can take advantage of several new technologies to do just that. This paper is based on the development project “Advanced Thermal Management in Aeronautics” (ATMIA). Project ATMIA focuses on the use of Loop Heat Pipes (LHPs) in the aeronautical industry, specifically their onboard feasibility and the unique requirements found on an aeronautical platform such as those due to vibrations, gravitational forces and the need for disassembly due to maintenance. LHPs are passive two-phase devices that allow free-energy heat transportation between certain subsystems without needing additional power consumption. Their use in aeronautics is interesting as they can passively transport seemingly “waste” heat to areas where it can be reused.
2014-09-16
Technical Paper
2014-01-2195
James H. Graham, Roger Dixon, Peter Hubbard, Ian Harrington
On future UAVs it is envisaged that the power requirements of all on-board electrical systems will increase. In most flight (mission) situations the installed power generation will have adequate capacity to operate the aircraft. It is possible that during abnormal situations such as coolant blockage the generators on-board may be forced to operate under very high load conditions. The main failure mechanism for a generator is overheating and subsequent disintegration of windings, hence the research problem being addressed here is to manage the loads upon the generator to prevent overheats. The research presented here summarizes the modeling of the generator and formation of the load management system. Results are presented showing the system reallocating loads after a fault during flight, preventing overheat of the generators and successfully completing the mission.
2014-09-16
Technical Paper
2014-01-2224
Stephen Emo, Jamie Ervin, Travis E. Michalak, Victor Tsao
Abstract Numerous previous studies have highlighted the potential efficiency improvements which can be provided to aircraft thermal management systems by the incorporation of vapor cycle systems (VCS), either in place of, or in conjunction with, standard air cycle systems, for providing the needed thermal management for aircraft equipment and crews. This paper summarizes the results of a cycle-based VCS control architecture as tested using the Vapor Cycle System Research Facility (VCSRF) in the Aerospace Systems Directorate of the Air Force Research Laboratory at Wright-Patterson Air Force Base. VCSRF is a flexible, dynamic, multi-evaporator VCS which incorporates electronic expansion valves and a variable speed compressor allowing the flexibility to test both components and control schemes. The goal of this facility is to reduce the risk of incorporating VCS into the thermal management systems (TMS) of future advanced aircraft. In this paper, the authors discuss the hardware configuration, as well as the differences between a baseline control architecture (consisting of evaporator superheat and system capacity control) and the suggested cycle-based control.
2014-09-16
Technical Paper
2014-01-2225
Hidefumi Saito, Shoji Uryu, Norio Takahashi, Noriko Morioka, Hitoshi Oyori
Abstract To improve an energy optimization issue of ECS for MEA, we propose our concept in which ACS is replaced with VCS. A VCS is generally evaluated as auxiliary or limited cooling system of an aircraft. Cooling demand of commercial aircraft usually becomes large due to ventilation air at hot day conditions. In case of using conventional VCS for whole cooling demand, the ECS becomes too heavy as aircraft equipment. Though ACS's light weight is advantageous, the issue that VCS will be available for aircraft ECS is important for saving energy. ECS of commercial aircraft should work for three basic functions, i.e. pressurization, ventilation, and temperature control. The three functions of the ECS for bleed-less type of MEA can be distributed among equipment of the ECS. MDFAC works for pressurization and ventilation. Therefore, we should select appropriate system for only temperature control. For the function of temperature control, system with higher COP should be selected due to energy saving.
2014-09-16
Technical Paper
2014-01-2213
Noriko Morioka, Hidefumi Saito, Norio Takahashi, Manabu Seta, Hitoshi Oyori
Abstract Electrical power management is a key technology in the AEA (All-Electric Aircraft) system, which manages the supply and demand of the electrical power in the entire aircraft system. However, the AEA system requires more than electrical power management alone. Adequate thermal management is also required, because the heat generated by aircraft systems and components increases with progressive system electrification, despite limited heat-sink capability in the aircraft. Since heat dissipation from power electronics such as electric motors, motor controllers and rectifiers, which are widely introduced into the AEA, becomes a key issue, an efficient cooling system architecture should be considered along with the AEA system concept. The more-electric architecture for the aircraft has been developed; mainly targeting reduced fuel burn and CO2 emissions from the aircraft, as well as leveraging ease of maintenance with electric/electronic components. The AEA should pursue more efficient and eco-friendlier systems, which are easier to maintain than those of conventional aircraft/MEA (More-Electric Aircraft), to enhance benefits for passengers and operators.
2014-09-16
Technical Paper
2014-01-2220
Jesse Miller, John Hoke, Frederick Schauer
Abstract Two compact intercoolers are designed for the Rotax 914 aircraft engine to increase engine power and avoid engine knock. A study is performed to investigate the effects of unsteady airflow on intercooler performance. Both intercoolers use air-to-liquid cross flow heat exchangers with staggered fins. The intercoolers are first tested by connecting the four air outlets of the intercooler to a common restricted exit creating a constant back pressure which allows for steady airflow. The intercoolers are then tested by connecting the four air outlets to a 2.4 liter, 4 cylinder engine head and varying the engine speed from 6000 to 1200 RPM corresponding to decreasing flow steadiness. The test is performed under average flight conditions with air entering the intercooler at 180°F and about 5 psig. Results from the experiment indicate that airflow unsteadiness has a significant effect on the intercooler's performance. Temperature spread across the intercooler's outlets varies from 30°F to 5°F as airflow unsteadiness increases.
2014-09-16
Technical Paper
2014-01-2160
Wei Wu, Yeong-Ren Lin, Louis Chow
Abstract In this paper, we address the thermal management issues which limit the lifespan, specific power and overall efficiency of an air-cooled rotary Wankel engine used in Unmanned Air Vehicles (UAVs). Our goal is to eliminate the hot spots and reduce the temperature gradients in the engine housing and side plates by aggressive heat spreading using heat pipes. We demonstrate by simulation that, for a specific power requirement, with heat spreading and more effective heat dissipation, thermal stress and distortion can be significantly reduced, even with air cooling. The maximum temperature drop was substantial, from 231°C to 129°C. The temperature difference (measure of temperature uniformity) decreased by 8.8 times (from 159°C to 18°C) for a typical UAV engine. Our heat spreaders would not change the frontal area of the engine and should have a negligible impact on the installed weight of the propulsion assembly. We expect our approach could lead to a very significant reduction in thermal stress-induced warping which is primarily responsible for wear and high friction.
2014-09-16
Technical Paper
2014-01-2155
Javier A. Parrilla
Abstract Current industry trends demonstrate aircraft electrification will be part of future platforms in order to achieve higher levels of efficiency in various vehicle level sub-systems. However, electrification requires a substantial change in aircraft design that is not suitable for re-winged or re-engined applications as some aircraft manufacturers are opting for today. Thermal limits arise as engine cores progressively get smaller and hotter to improve overall engine efficiency, while legacy systems still demand a substantial amount of pneumatic, hydraulic and electric power extraction. The environmental control system (ECS) provides pressurization, ventilation and air conditioning in commercial aircraft, making it the main heat sink for all aircraft loads with exception of the engine fuel thermal management system. To mitigate the architecture thermal limits in an efficient manner, the form in which the ECS integrates with the engine will have to be enhanced as to reduce the overall energy consumed and achieve an energy optimized solution.
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
2014-01-2152
Pedro Del valle, Pablo Blazquez Munoz
Abstract Advance thermal management systems are being developed to optimise the energy balance within aircraft. This is being done in parallel to the concept of the More Electrical Aircraft (MEA) which has been developing throughout the last decades. The objective of such complex systems is to use efficiently the hot and cold sources available within the air vehicle to reduce the engine fuel consumption. A reduction of electrical power consumption, minimisation of weight, optimisation of aircraft aerodynamics (for example RAM inlets area minimisation) and the reduction of bleed air from engine all result in a fuel consumption saving. Any thermal management system to optimise energy consumption implies complex and advanced systems. This requires a high engineering effort to design and integrate the system within an aircraft due to the large quantity of variables and interfaces that need to be taken into account. Models and simulations are essential from the beginning of the system development and design phase.
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
2014-01-2111
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
2014-01-2201
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.
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