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Technical Paper

“Aluminium Hot Forming: - Opportunities and Challenges in Automotive Light Weighting”

2023-05-25
2023-28-1304
In today’s Automotive world, there is NO need to advocate “Light weighting”. Government policies for carbon footprint reduction combined with high safety standards are driving OEMs to adopt advanced manufacturing technologies. Steel hot forming is selected as most preferred way to reduce weight as it is easy to adopt and commercially known. It had many advantages compare to conventional cold stamping of standard and high tensile steel. The process consists of heating blank to nearly 1000 °C and quenching it in tool to for martensitic structure. Higher strength up to 2000 MPa can be achieved by this process. There are many examples where part weight is reduced by 15 to 20 % by this method. But Steel hot forming has limitation as specific density of steel is still high. Thus, there is limitation to its weight reduction capability. For further reduction, OEMs have started exploring Aluminium hot forming.
Technical Paper

“All Electric” Controls and Accessories for Ground Vehicle Gas Turbine Propulsion Systems

1986-02-01
860238
This paper discusses the use of electromechanical devices as the kinematic portions of a microprocessor based gas turbine control system. Specific applications are: 1. An electric motor driven, positive displacement pump, which provides metered high pressure fuel to the distribution manifold. Fuel metering to be provided by varying the motor angular velocity. 2. An electric motor driven lube oil pump. 3. Electromechnical actuators for motion and control of compressor and power turbine variable geometry. 4. A starter/generator integral with the gas generator. Topics covered include: Comparison to conventional hydro-mechanical systems. Response characteristics of the fuel pump and actuator systems. Brushless D.C. motor characteristics. Power electronics requirements for brushless D.C. motors. Control electronics interface with brushless D.C. motor systems. Reliability and maintainability issues. Diagnostic/prognostic enhancements.
Technical Paper

‘Wheel Slip-Based’ Evaluation of Road Friction Potential for Distributed Electric Vehicle

2016-04-05
2016-01-1667
As a typical parameter of the road-vehicle interface, the road friction potential acts an important factor that governs the vehicle motion states under certain maneuvering input, which makes the prior knowledge of maximum road friction capacity crucial to the vehicle stability control systems. Since the direct measure of the road friction potential is expensive for vehicle active safety system, the evaluation of this variable by cost effective method is becoming a hot issue all these years. A ‘wheel slip based’ maximum road friction coefficient estimation method based on a modified Dugoff tire model for distributed drive electric vehicles is proposed in this paper. It aims to evaluate the road friction potential with vehicle and wheel dynamics analyzing by using standard sensors equipped on production vehicle, and fully take the advantage of distributed EV that the wheel drive torque and rolling speed can be obtained accurately.
Technical Paper

‘Skins’ by Design: Humans to Habitats

2003-07-07
2003-01-2655
Whether we live on land, underwater, or out there in space, what makes it possible is our ‘skin’. The one we were born with, the one we wear, the one we live in, and the one we travel in. The skin is a response to where we live: it protects as our first line of defense against a hostile environment; it regulates as part of our life-support system; and, it communicates as our interface to everything within and without. In the context of space architecture – we, our space suits, vehicles and habitats are all equipped with highly specialized ‘skins’ that pad us, protect us and become an integral part of the design expression. This paper approaches the subject from a holistic perspective considering ‘skins’ and their manifestation as structure, as vessel, as texture, and as membrane. The paper then goes on to showcase innovative use of materials in practice through two case studies: the ‘spacesuit’ and ‘inflatable habitats’.
Technical Paper

λDSF: Dynamic Skip Fire with Homogeneous Lean Burn for Improved Fuel Consumption, Emissions and Drivability

2018-04-03
2018-01-0891
Dynamic skip fire (DSF) has shown significant fuel economy improvement potential via reduction of pumping losses that generally affect throttled spark-ignition (SI) engines. In DSF operation, individual cylinders are fired on-demand near peak efficiency to satisfy driver torque demand. For vehicles with a downsized-boosted 4-cylinder engine, DSF can reduce fuel consumption by 8% in the WLTC (Class 3) drive cycle. The relatively low cost of cylinder deactivation hardware further improves the production value of DSF. Lean burn strategies in gasoline engines have also demonstrated significant fuel efficiency gains resulting from reduced pumping losses and improved thermodynamic characteristics, such as higher specific heat ratio and lower heat losses. Fuel-air mixture stratification is generally required to achieve stable combustion at low loads.
Technical Paper

β-Carotene Content of Dehydrated Hydroponic Sweetpotatoes Grown under Different Lighting Conditions

2007-07-09
2007-01-3051
The sweetpotato (Ipomoea batatas L. LAM.) is a versatile and underexploited food crop. Consumption of sweetpotato based processed foods provide β-carotene, which is the major precursor of vitamin A. The sweetpotato has the potential to provide antioxidants that may help reduce the radiation risks astronauts face while in space. Therefore the objective of this experiment was to evaluate β-carotene in dehydrated hydroponic sweetpotato cultivars. Hydroponic cultivars WHATLEY/LORETAN and NCC-58 were grown with and without 7-10 μmole of light. WHATLEY/LORETAN contained the highest amount of β-carotene content average of 31 μg/100g in dehydrated hydroponic sweetpotatoes compared to NCC-58 with 18.5 μg/100g.
Technical Paper

ΔV, BEV and Coefficient of Restitution Relationships as Applied to the Interpretation of Vehicle Crash Test Data

2001-03-05
2001-01-0499
Prior theoretical work relating barrier equivalent velocity (BEV) and change in vehicle velocity, ΔV, has either neglected restitution or mischaracterized its role. Based on fundamental structural dynamics principles, improved relationships between BEV, ΔV, coefficient of restitution, and vehicle mass and stiffness are formulated. These corrected relationships are then utilized in the assessment of four classes of vehicular impact testing: vehicle to vehicle (VTV), vehicle to infinitely massive rigid barrier (VRB), vehicle to infinitely massive compliant barrier (VCB) and vehicle to finite mass movable rigid barrier (VFMB).
Technical Paper

µMist® - The next generation fuel injection system: Improved atomisation and combustion for port-fuel-injected engines

2011-08-30
2011-01-1890
The Swedish Biomimetics 3000's μMist® platform technology has been used to develop a radically new injection system. This prototype system, developed and characterized with support from Lotus, as part of Swedish Biomimetics 3000®'s V₂IO innovation accelerating model, delivers improved combustion efficiency through achieving exceptionally small droplets, at fuel rail pressures far less than conventional GDI systems and as low as PFI systems. The system gives the opportunity to prepare and deliver all of the fuel load for the engine while the intake valves are open and after the exhaust valves have closed, thereby offering the potential to use advanced charge scavenging techniques in PFI engines which have hitherto been restricted to direct-injection engines, and at a lower system cost than a GDI injection system.
Standard

xEV Labels to Assist First and Second Responders, and Others

2017-03-02
CURRENT
J3108_201703
This recommended practice prescribes clear and consistent labeling methodology for communicating important xEV high voltage safety information. Examples of such information include identifying key high voltage system component locations and high voltage disabling points. These recommendations are based on current industry best practices identified by the responder community. Although this recommended practice is written for xEVs with high voltage systems, these recommendations can be applied to any vehicle type.
Journal Article

uACPC: Client-Initiated Privacy-Preserving Activation Codes for Pseudonym Certificates Model

2020-07-27
Abstract With the adoption of Vehicle-to-everything (V2X) technology, security and privacy of vehicles are paramount. To avoid tracking while preserving vehicle/driver’s privacy, modern vehicular public key infrastructure provision vehicles with multiple short-term pseudonym certificates. However, provisioning a large number of pseudonym certificates can lead to an enormous growth of Certificate Revocation Lists (CRLs) during its revocation process. One possible approach to avoid such CRL growth is by relying on activation code (AC)-based solutions. In such solutions, the vehicles are provisioned with batches of encrypted certificates, which are decrypted periodically via the ACs (broadcasted by the back-end system). When the system detects a revoked vehicle, it simply does not broadcast the respective vehicle’s AC. As a result, revoked vehicles do not receive their respective AC and are prevented from decrypting their certificates.
Technical Paper

the use of Radioactive Tracer Techniques to determine the effect of operating variables on Eng ine Wear

1960-01-01
600035
RADIOTRACERS were used to study the wear effects of engine speed, load, jacket water temperature, fuel temperature, and chromium-plated rings in a medium-speed diesel engine. One distillate fuel and two residual fuels were tested. This paper describes the tests and their results. Some of the conclusions are: The brake thermal efficiency with high viscosity residual fuel was essentially equal to distillate diesel fuel over a wide range of loads, providing the residual fuel was heated to the proper temperature. Engine speed did not affect the wear rate of cast-iron rings when distillate fuel was used, while with residual fuel wear decreased with increased speed. With distillate fuel, engine load had essentially no effect on cast-iron ring wear. With residual fuel, decreasing engine load produced a marked increase in ring wear*
Technical Paper

the potential of Unconventional Powerplants for Vehicle Propulsion

1959-01-01
590039
COMPARISON of work capacity per unit mass and volume of different energy carriers shows that liquid hydrocarbons are superior to other energy sources. Solar and nuclear powerplants as well as their use in conjunction with a steam engine are examined in this paper. Suitability of an electric drive is discussed. Using a production 2-stroke diesel engine and its development forecast, a comparison is made of spark ignition, diesel, and gas turbine engines. The status of the free-piston engine turbine combination is reviewed.
Technical Paper

the identification and characterization of RUMBLE AND THUD

1960-01-01
600015
SIMULTANEOUS RECORDINGS of cylinder pressure, audible sound, and crankshaft motion have shown that rumble is a noise associated with bending vibrations of the crankshaft. The vibrations are caused by abnormally high rates of pressure rise near the top dead center piston position. In this study the high rates of pressure rise were obtained by inducting deposits into the the engine. Thud is a torsional vibration of the crankshaft, similar in sound to rumble but resulting from much earlier occurrence of the maximum rates of pressure rise. Rumble vibrations consisted of a fundamental frequency of 600 cps and higher harmonics in the 11/1 compression ratio V-8 laboratory engine used in the investigation. The audible noise of rumble was predominantly composed of the second harmonic or about 1200 cps.
Technical Paper

the behavior of Radiation-Resistant ANP TURBINE LUBRICANTS

1959-01-01
590051
RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.
Technical Paper

some metallurgical aspects of … Pontiac V-8 Engine Pearlitic Malleable Iron Crankshaft

1958-01-01
580013
PEARLITIC malleable iron crankshafts are being used in the new Pontiac engine as a result of recent developments. This paper discusses the physical properties of pearlitic malleable iron such as elastic modulus, fatigue endurance, and tensile strength. According to the author, definite machining economies result from using pearlitic malleable iron crankshafts.
Technical Paper

preliminary design considerations for the Structure of a Trisonic Transport

1960-01-01
600045
STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*
Technical Paper

p>Thermomechanical Analysis of the Cylinder Head and Cylinder Block with the Liner of AFV Diesel Engine

2011-10-06
2011-28-0118
This paper deals with the Coupled thermo mechanical analysis of a cylinder head, cylinder block and crank case with the liner of an uprated engine. The existing engine develops 780 hp output with mechanical driven supercharger and the engine is uprated to 1000 hp by replacing the supercharger with a turbocharger and new Fuel injection equipment. For uprating any engine, the piston and cylinder head are the most vulnerable members due to increased mechanical and thermal loadings. Mechanical loading is due to the gas pressure in the gas chamber and its magnitude can be judged in terms of peak pressure. Thermal loading is due to temperature and the heat transfer conditions in the piston surface, cylinder liner and the cylinder head. The relative importance of the various loads applied on the head and cylinder block in operation are assessed and a method of predicting their influence on the structural integrity of the components described.
Technical Paper

mDSF: Improved Fuel Efficiency, Drivability and Vibrations via Dynamic Skip Fire and Miller Cycle Synergies

2019-04-02
2019-01-0227
mDSF is a novel cylinder deactivation technology developed at Tula Technology, which combines the torque control of Dynamic Skip Fire (DSF) with Miller cycle engines to optimize fuel efficiency at minimal cost. mDSF employs a valvetrain with variable valve lift plus deactivation and novel control algorithms founded on Tula’s proven DSF technology. This allows cylinders to dynamically alternate among 3 potential states: high-charge fire, low-charge fire, and skip (deactivation). The low-charge fire state is achieved through an aggressive Miller cycle with Early Intake Valve Closing (EIVC). The three operating states in mDSF can be used to simultaneously optimize engine efficiency and driveline vibrations. Acceleration performance is retained using the all-cylinder, high-charge firing mode.
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