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2015-09-29
Technical Paper
2015-01-2888
Devadatta Mukutmoni, Tristan Donley, Jaehoon Han, Karthik Mahadevan Muthuraman, P. David Campbell, Tom Mertz
Design and evaluation of construction equipments and vehicles constitute a very important but expensive and time consuming part of the engineering process. This is especially so because of the large number of variants and the relatively small production volume of each variant leading to large costs of engineering and design of vehicles as a proportion of total sales. A simulation based methodology could potentially reduce the cost and time of the entire design process. In this study, we look into an alternative simulation based approach to the design process. However, given the enormity of the task, we limit the scope of this investigation to design evaluation and improvement for thermal considerations only. In particular, thermal evaluation of the electronic control units are looked into.
2015-09-29
Technical Paper
2015-01-2792
Olof Erlandsson, Thomas Skare, Arnaud Contet
The automotive industry have become more and more interesting in recovering waste heat from internal combustion engines (ICE) , especially with future, tighter fuel and CO2 emission regulations in sight. Potential systems that recover waste heats have in all in common that they have lower efficiency than the ICE itself (otherwise the use of ICE would be questioned), hence the recovery system also need to expel a lot of waste heat to the surrounding. In this study we consider a simple automotive Rankine waste heat recovery system (WHRS) on a long-haulage truck that transform some of the ICE waste heat into useful energy but it still needs to return remaining heat to the surrounding, either through a direct condenser (CDS) or from an indirect CDS via a Low temperature radiator (LTR) to the surrounding, and this in the regular cooling module of the vehicle.
2015-09-29
Technical Paper
2015-01-2809
Sajit Pillai, Julian LoRusso, Matthew Van Benschoten
Abstract Cylinder deactivation was evaluated both analytically and experimentally on a six cylinder diesel engine to understand potential fuel economy and emission improvements. The benefits of cylinder deactivation in Spark Ignited (SI) engines are well documented, however there is little information on the application of the technology for diesel engines. The analytical model was evaluated at low load, steady state conditions. The modified baseline model that includes cylinder deactivation maintains comparable emission levels through the optimization of Exhaust Gas Recirculation (EGR) and Variable Geometry Turbocharger (VGT). The results demonstrated reductions in Brake Specific Fuel Consumption (BSFC) and higher exhaust gas temperatures for low and part load operating points. An experimental test validated the analytical results. Disabling fuel injectors and the valve train on half of the engine's cylinders allowed for the implementation of cylinder deactivation.
2015-09-15
Journal Article
2015-01-2416
Charles E. Oberly, Michelle Bash, Benjamin R. Razidlo, Travis E. Michalak, Fernando Rodriguez
Abstract An IPTMS hardware facility has been established in the laboratories of the Aerospace Systems Directorate of the Air Force Research Laboratory (AFRL) at Wright-Paterson Air Force Base (WPAFB). This hardware capability was established to analyze the transient behavior of a high power Electrical Power System (EPS) coupled virtually to a Thermal Management System (TMS) under fast dynamic loading conditions. The system incorporates the use of dynamic electrical load, engine emulation, energy storage, and emulated thermal loads operated to investigate dynamics under step load conditions. Hardware architecture and control options for the IPTMS are discussed. This paper summarizes the IPTMS laboratory demonstration system, its capabilities, and preliminary test results.
2015-09-15
Technical Paper
2015-01-2561
Fernando Stancato, Sandro Conceicao, Ramon Papa, Luis Santos
Abstract Nowadays CFD analysis including virtual manikins is vastly applied to evaluate thermal comfort inside different working environments, such as buildings cars and aircrafts. Inside aircraft cabins, added to the numerical challenges due to geometrical complexity, the available subjective responses used to judge occupant local thermal comfort are usually based on buildings and cars experiments [1]. In the present paper however, it is applied an aircraft based subjective responses to evaluate thermal comfort which was specifically developed using regional jet mock-up experiments. The evaluation for the two approaches will be compared providing insight of the main differences.
2015-09-15
Technical Paper
2015-01-2582
Andre Silva, Nayeff Najjar, Shalabh Gupta, Paul D'Orlando, Rhonda Walthall
Abstract The Environmental Control System (ECS) of an aircraft provides thermal and pressure control of the engine bleed air for comfort of the crew members and passengers onboard. For safe and reliable operation of the ECS under complex operating environments, it is critical to detect and diagnose performance degradations in the system during early phases of fault evolution. One of the critical components of the ECS is the heat exchanger, which ensures proper cooling of the engine bleed air. This paper presents a wavelet-based fouling diagnosis approach for the heat exchanger.
2015-09-15
Technical Paper
2015-01-2420
Henry A. Catherino
Abstract The heat generation rate of a lithium ion cell was estimated using a reversible heat generation rate equation. Because the equation is based on the energy conservation law, the influence of kinetically slow processes should be considered. In this analysis, the influence of kinetically slow processes is present but it is small within the domain of the test measurements. This approximation can be of significant usefulness for modeling the thermal response of single cells and multi-cell batteries.
2015-09-15
Technical Paper
2015-01-2419
Naoki Seki, Noriko Morioka, Hidefumi Saito, Hitoshi Oyori
Abstract This paper describes the concept of an air/fuel integrated thermal management system, which employs the VCS (Vapor Cycle System) for the refrigeration unit of the ECS (Environment Control System), while exchanging the heat between the VCS refrigerant and the fuel into the engine, and presents a feasibility study to apply the concept to the future all electric aircraft systems. The heat generated in an aircraft is transferred to the ECS heat exchanger by the recirculation of air and exhausted into the ram air. While some aircraft employ the fluid heat transfer loop, the transferred heat is exhausted into the ram air. The usage of ram air for the cooling will increase the ram drag and the fuel consumption, thus, less usage of ram air is preferable. Another source for heat rejection is the fuel. The heat exchange with the fuel does not worsen the fuel consumption, thus, the fuel is a preferable source.
2015-09-15
Technical Paper
2015-01-2415
Kyle Shimmin, Greg Russell, Robert A. Reuter, Steven Iden
Abstract A reduced order dynamic aircraft model has been created for the purpose of enabling constructive simulation studies involving integrated thermal management subsystems. Such studies are motivated by the increasing impact of on-board power and thermal subsystems to the overall performance and mission effectiveness of modern aircraft. Previous higher-order models that have been used for this purpose have the drawbacks of much higher development time, along with much higher execution times in the simulation studies. The new formulation allows for climbs, accelerations and turns without incurring computationally expensive stability considerations; a dynamic inversion control law provides tracking of user-specified mission data. To assess the trade-off of improved run-time performance against model capability, the reduced order formulation is compared to a traditional six degree-of-freedom model of the same air vehicle.
2015-09-15
Technical Paper
2015-01-2418
Ricardo Gandolfi, Luiz Ribeiro, Jorge Oliveira, Kleber Paiva, Marcia Mantelli
Abstract Due to the increasing power density of onboard electric and electronic equipment and heat dissipation in civil and military aircraft, more efficient ways of transferring heat and new cooling techniques are necessary. A passive heat transfer prototype was developed and experimentally evaluated in laboratory and on ground and flight tests in an Embraer test aircraft. The passive heat transfer device consists of a loop-thermosyphon with two condensers and a common evaporator, using water as the heat transfer working fluid. An electric resistance and a variable power source were used to dissipate heat inside the evaporator simulating heat transfer from an onboard electronics bay. The fuselage/external air stream and the air flow inside an air conditioning system duct were used as heat sinks. Prior to flight test, laboratory tests were conducted simulating ground and flight operations.
2015-09-06
Technical Paper
2015-24-2533
Mirko Bovo, Joop Somhorst
The focus on engine thermal management is rapidly increasing due to the significant effect of heat losses on fuel consumption, engine performance and emissions. This work presents a time resolved, high resolution 3D engine heat balance model, including all relevant components. Notably, the model calculates the conjugated heat transfer between the solid engine components, the coolant and the oil. Both coolant and oil circuits are simultaneously resolved with a CFD solver in the same finite volume model as the entire engine solid parts. The model includes external convection and radiation. The necessary boundary conditions of the thermodynamic cycle (gas side) are mapped from a calibrated 1D gas exchange model of the same engine. The boundary conditions for the coolant and at the oil circuits are estimated with 1D models of the systems. The model is calibrated and verified with measurement data from the same engine as modeled.
2015-09-06
Journal Article
2015-24-2443
Jesus Benajes, Jaime Martin, Antonio Garcia, David Villalta, Alok Warey, Vicent Domenech, Alberto Vassallo
In the last two decades engine research has been mainly focused on reducing pollutant emissions. This fact together with growing awareness about the impacts of climate change are leading to an increase in the importance of thermal efficiency over other criteria in the design of internal combustion engines (ICE). In this framework, the heat transfer to the combustion chamber walls can be considered as one of the main sources of indicated efficiency diminution. In particular, in modern direct-injection diesel engines, the radiation emission from soot particles can constitute a significant component of the efficiency losses. Thus, the main of objective of the current research was to evaluate the amount of energy lost to soot radiation relative to the input fuel chemical energy during the combustion event under several representative engine loads and speeds. Moreover, the current research characterized the impact of different engine operating conditions on radiation heat transfer.
2015-09-06
Journal Article
2015-24-2536
Julien Bouilly, Francois Lafossas, Ali Mohammadi, Roger Van Wissen
Abstract In the automotive field, reducing harmful pollutant, CO2 emissions and fuel consumption of vehicles while increasing customer comfort is a continuous challenge that requires more and more sophisticated technology implementations. However, it is often difficult to anticipate the advantages and drawbacks of a technology without having its prototype parts and/or knowing the optimal control strategy. In order to meet these challenges, the authors have developed a vehicle thermal model in AMESim platform to evaluate the benefits of an Active Grille Shutter (AGS) on fuel economy when applied. The vehicle model was based on a C-Segment vehicle powered by a 1.4L Diesel engine. The complete oil and coolant circuits were modeled as well as a friction model based on engine coolant and oil temperature.
2015-09-03
WIP Standard
J3109
To define a test standard for the measurement of efficiency and a usage-weighted evaluation for the purpose of reporting to EPA for emissions credits.
2015-08-28
Standard
J2064_201508
The Scope of SAE J2064 covers coupled hose assemblies intended for containing and circulating lubricant, liquid and gaseous R134a and/or R-1234yf refrigerant in automotive air-conditioning systems. Historically, requirements for the hose used in coupled automotive refrigerant air conditioning assemblies was included in SAE J2064. SAE J2064 has been changed to establish the requirements for factory and field coupled hose assemblies. SAE J3062 has been issued to define requirements for the hose used in these assemblies into its own standard. SAE J2064 also provides the necessary values used in SAE J2727 Mobile Air Conditioning System Refrigerant Emission charts for R-134a and R-1234yf. The certified coupling of MAC hose assemblies is required in meeting certain regulatory requirements. A hose which has met the requirements of SAE J3062 and certified in J2911 must be used as part of the coupled assembly.
2015-08-04
Magazine
Chipping in to get more from battery packs Power semiconductors help extend range, keeping their cool while improving efficiency at higher voltages.
2015-07-13
Standard
ARP1796B
This SAE Aerospace Recommended Practice (ARP) discusses design philosophy, system and equipment requirements, installation environment and design considerations for military and commercial aircraft systems within the Air Transport Association (ATA) ATA 100 specification, Chapter 36, Pneumatic. This ATA system/chapter covers equipment used to deliver compressed air from a power source to connecting points for other systems such as air conditioning, pressurization, ice protection, cross-engine starting, air turbine motors, air driven hydraulic pumps, on board oxygen generating systems (OBOGS), on board inert gas generating systems (OBIGGS), and other pneumatic demands.
2015-07-08
Standard
J3030_201507
The purpose of this SAE Standard is to establish the specific minimum equipment requirements for recovery/recycling/recharge equipment intended for use with both R-1234yf and R-134a in a common refrigerant circuit that has been directly removed from, and is intended for reuse in, mobile air-conditioning (A/C) systems. This document does not apply to equipment used for R-1234yf and R-134a having a common enclosure with separate circuits for each refrigerant, although some amount of separate circuitry for each refrigerant could be used.
2015-07-01
Standard
J1726_201507
This SAE Recommended Practice provides test methods and criteria for evaluating the internal cleanliness and air leakage for engine charge air coolers. This SAE Recommended Practice also provides nomenclature and terminology in common use for engine charge air coolers, related charge air cooling system components, and charge air cooling system operational performance parameters.
2015-06-30
Standard
J3062_201506
The Scope of SAE J3062 covers hose intended for containing and circulating lubricant, liquid and gaseous R134a and/or R-1234yf refrigerant in automotive air-conditioning systems. The hose shall be designed to minimize permeation of the refrigerant, contamination of the system, and to be functional over a temperature range of -30 to 125 °C. Specific construction details are to be agreed upon between the user and supplier. Requirements for the hose used in coupled automotive refrigerant air-conditioning assemblies had been included in SAE J2064. SAE J3062 separates requirements for the hose used in these assemblies into its own standard. SAE J2064 also provides the necessary values used in SAE J2727 Mobile Air-Conditioning System Refrigerant Emission charts for R-134a and R-1234yf. Mobile air-conditioning system refrigerant emissions rates are established in SAE J2727 Emission charts and are important.
2015-06-15
Technical Paper
2015-01-2273
Curtis Jones, Zhengyu Liu, Suhas Venkatappa, James Hurd
Abstract This paper presents the methodology of predicting vehicle level automotive air-handling system air-rush noise sound quality (SQ) using the sub-system level measurement. Measurement setup in both vehicle level and sub-system levels are described. To assess the air-rush noise SQ, both 1/3 octave band sound pressure level (SPL) and overall Zwicker's loudness are used. The “Sound Quality Correlation Functions (SQCF)” between sub-system level and vehicle level are developed for the specified climate control modes and vehicle segment defined by J.D. Power & Associates, while the Zwicker's loudness is calculated using the un-weighted predicted 1/3 octave band SPL. The predicting models are demonstrated in very good agreement with the measured data. The methodology is applied to the development of sub-system SQ requirement for upfront delivery of the optimum design to meet global customer satisfaction
2015-06-15
Technical Paper
2015-01-2249
Saad Bennouna, Said Naji, Olivier Cheriaux, Solene Moreau, Boureima Ouedraogo, Jean Michel Ville
Abstract Passengers' thermal comfort inside a car cabin is mainly provided by the Heating, Ventilation and Air Conditioning (HVAC) module. Air provided by HVAC is blown via a blower, passing through different components: flaps, thermal exchangers, ducts… and then distributed to car cabin areas. Interaction between airflow and HVAC components generates noises that emerge in car cabin. Due to this fact, noise is naturally created and its level is linked to flow rate. Valeo is aiming, though CEVAS project, to develop a prediction tool which will provide HVAC spectrum and sound quality data. This tool will be based, in particular, on aeroacoustic measurements using 2N-ports model and Particle Image Velocimetry methods to provide characteristics of HVAC components.
2015-06-15
Journal Article
2015-01-2275
Manfred Koberstein, Zhengyu Liu, Curtis Jones, Suhas Venkatappa
Abstract In the thermal expansion valve (TXV) refrigerant system, transient high-pitched whistle around 6.18 kHz is often perceived following air-conditioning (A/C) compressor engagements when driving at higher vehicle speed or during vehicle acceleration, especially when system equipped with the high-efficiency compressor or variable displacement compressor. The objectives of this paper are to conduct the noise source identification, investigate the key factors affecting the whistle excitation, and understand the mechanism of the whistle generation. The mechanism is hypothesized that the whistle is generated from the flow/acoustic excitation of the turbulent flow past the shallow cavity, reinforced by the acoustic/structural coupling between the tube structural and the transverse acoustic modes, and then transmitted to evaporator. To verify the mechanism, the transverse acoustic mode frequency is calculated and it is coincided to the one from measurement.
2015-06-15
Journal Article
2015-01-2276
Zhengyu Liu, Donald Wozniak, Manfred Koberstein, Curtis Jones, Jan Xu, Suhas Venkatappa
Abstract Refrigerant flow-induced gurgling noise is perceived in automotive refrigerant systems. In this study, the condition of the gurgling generation is investigated at the vehicle level and the fundamental root cause is identified as the two-phase refrigerant flow entering the TXV for system equipped with variable displacement compressors. By conducting literature reviews, the acoustic characteristics of the flow patterns and the parameters affecting the flow regimes in horizontal and vertical tubes are summarized. Then the gurgling mechanism is explained as the intermittent flow is developed at the evaporator inlet. In the end, the improved and feasible design for avoiding the intermittent flow (slug, plug or churn flow) or minimizing its formation is proposed and verified in refrigerant subsystem (RSS) level. Finally, the guidelines for the attenuation and suppression of the gurgle are provided.
2015-06-15
Journal Article
2015-01-2323
Abdelhakim Aissaoui, Ravindra S Tupake, Vilas Bijwe, Mohammed Meskine, Franck Perot, Alain Belanger, Rohit J Vaidya
For the automotive industry, acoustic comfort is of increasing importance. The market and customer expectation make the HVAC system noise quality a question to be addressed as early as possible in the vehicle development process. On one hand, the so-called traditional sources of annoyance such as engine, road-tires contact, exhaust systems and wind-noise have been significantly reduced for most traditional combustion engine vehicles. On the other hand, considered in the past as secondary noise sources, HVAC systems become the main sources for hybrid and electric and Stop-start vehicles. Previous studies have demonstrated the ability of a CFD/CAA approach based on the Lattice Boltzmann Method (LBM) to predict HVAC system noise including real and complex ducts, registers, mixing unit and blower geometries.
2015-06-10
WIP Standard
J2914
This document provides an overview on how and why EGR coolers are utilized, defines commonly used nomenclature, discusses design issues and trade-offs, and identifies common failure modes. The reintroduction of exhaust gas into the combustion chamber is just one component of the emission control strategy for internal combustion (IC) engines, both diesel and gasoline, and is useful in reducing exhaust port emission of Nitrogen Oxides (NOx). Other means of reducing NOx exhaust port emissions are briefly mentioned, but beyond the scope of this document.
2015-06-02
Standard
AIR1069B
Determine the required minimum oxygen concentration to be breathed prior to, during, and after a loss of cabin pressurization, and determine recommended means necessary to provide the required oxygen concentrations.
2015-05-29
Standard
ARP986D
This SAE Aerospace Recommended Practice (ARP) defines recommended analysis and test procedures for qualification of pneumatically, electrically, manually, and hydraulically actuated air valves. They may be further defined as valves that function in response to externally applied forces or in response to variations in upstream and/or downstream duct air conditions in order to maintain a calibrated duct air condition (e.g., air flow, air pressure, air temperature, air pressure ratio, or air shutoff). Qualification testing performed on the airplane to verify compatibility of the valve function and stability as part of a complete system is outside the scope of this document. Refer to ARP1270 for design and certification requirements for cabin pressurization control system components. As this document is only a guide, it does not supersede or relieve any requirements contained in detailed Customer specifications.
2015-05-07
Standard
J2842_201505
The intent of this standard is to establish a framework to assure that all evaporators for R-744, R-1234yf, and R-445A mobile air conditioning (MAC) systems meet appropriate testing and labeling requirements. SAE J639 requires vehicle manufacturers to perform assessments to minimize reasonable risks in production MAC systems. The evaporator (as designed and manufactured) shall be part of that risk assessment and it is the responsibility of the vehicle manufacturer to assure all relevant aspects of the evaporator are included. It is the responsibility of all vehicle or evaporator manufacturers to comply with the standards of this document at a minimum. (Substitution of specific test procedures by vehicle manufactures that correlate well to field return data is acceptable.) As appropriate, this standard can be used as a guide to support risk assessments.
2015-05-01
Magazine
Unmanned Aerial Systems Deploying Next-Generation UAS Platforms with 3U VPX Unmanned Ground Vehicles UGVs - On the Cutting Edge of Thermal Management Unmanned Surface/Underwater Vehicles Controlling the Seas - Introducing a New Concept in Autonomous Surface/Underwater Vehicles Robotics Connectivity in Robotic Systems
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