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2014-10-16
WIP Standard
AS25050B
This specification covers the chromaticity and transmission requirements of equipment light transmitting ware in the descending order of transmission. It is intended for use in military aircraft lighting.
2014-10-15
WIP Standard
J2403DA
This document is intended to supplement SAE J2403 by providing the content of Table 1, Table 2, and Table 3 from SAE J2403 in a form that can be sorted and searched for easier use. It is NOT intended as a substitute for the actual document, and any discrepancies between this Digital Annex and the published SAE J2403 document must be resolved in favor of the published document. This document provides the content of Table 1 and Table 2 published in SAE J2403 into the single table in the 'Term' tab, while the 'Recommended Term Definitions' tab provides the content of Table 3 in SAE J2403 and the 'Glossary' tab provides the content of Table 4 in SAE J2403.
2014-10-15
WIP Standard
AS85731/1B
No scope available.
2014-10-15
WIP Standard
AS85731/2A
No scope available.
2014-10-15
WIP Standard
AS85731B
This specification covers positive locking fasteners intended for use in aircraft to secure electronic line replaceable units (LRUs).
2014-10-14
Standard
AS20708B
This specification relates to Synchros, 60 and 400 Hz. It is not complete in itself, but shall be used in conjunction with MIL DTL-81963, in which the latter shall be recognized as forming an inherent part of this specification. This standard requires a Qualified Products List (see 6.4).
2014-10-13
Technical Paper
2014-01-2590
Yuanzhe Zhong, Sahil Sane
Abstract Electronic controls in internal combustion engines require an in-cylinder combustion sensor to produce a feedback signal to the ECU (Engine Control Unit). Recent research indicated that the ion current sensor has many advantages over the pressure transducer, related mainly to lower cost. Modified glow plugs in diesel engines, and fuel injectors in both gasoline and diesel engines can be utilized as ion current sensors without the addition any part or drilling holes in the cylinder head needed for the pressure transducer. Multi sensing fuel injector (MSFI) system is a new technique which instruments the fuel injector with an electric circuit to perform multiple sensing tasks including functioning as an ion sensor in addition to its primary task of delivering the fuel into the cylinder. It is necessary to fundamentally understand MSFI system. In this study the author will firstly explore the influence of piston motion (as one side of variable capacitance) on the ion sensor signal through modeling and simulation, and then look into the origin of the MSFI signal of fuel injection; and finally the author will look at how to analyze MSFI signal to duplicate the injection command profile for on-board diagnostics (OBD).
2014-10-13
Technical Paper
2014-01-2584
Krisada Wannatong, Sompach Kongviwattanakul, Thananchai Tepimonrat, Thanadech Priroon
Abstract End of line test (EOL) of Engine Control Units (ECU) is the process of ECU functions validation before releasing ECUs to the car assembly process. Examples of ECU function that need to be validated are idle control, air path control and faults manager function. To perform EOL, a vehicle and a chassis dynamometer are used to enable control functions validation inside the ECU. However, this poses high operating cost and long setup time. This paper presents the development of Hardware-in-the-Loop (HiL) system, which imitates real vehicle behavior on a chassis dynamometer. The diesel high pressure pump model was developed using an empirical dynamic modeling approach. The engine model was developed using AVL BOOST RT software, an engine cycle simulation modeling approach. The vehicle model was developed using AVL CRUISE software. In order to interface the engine and vehicle models with the ECU, HiL system was implemented. In the new EOL process, the vehicle was operated following the Extra Urban Driving Cycle (EUDC) including short engine idling time.
2014-10-13
Technical Paper
2014-01-2589
Chunshan Li, Guoying Chen, Changfu Zong
Abstract The passive fault-tolerant approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles has been investigated in this study. An adaptive control based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization. The FTC approach is based on the reconfigurable control allocation which reallocates the generalized forces/moments among healthy actuators once the actuator failures is detected.
2014-10-13
Technical Paper
2014-01-2711
Nicolas Arnault, Guy Monsallier
Abstract Cold weather is a challenge for compression ignition engines. As Diesel fuel creates wax crystals when temperature goes down enough, it comes to plug the fuel filter and the fuel injection system, leading to undesirable effects like loss of power, engine stall after start or even the engine not starting at all. Moreover, it has been shown that FAME Biodiesel has additional negative impacts on vehicle cold flow operability. Despite fuel additives which can support cold conditions, the whole fuel injection system has to be designed to support engine operability in variable environments, meaning also in very cold conditions, with variable fuel qualities. The Diesel Fuel Filter is a key element of the fuel injection system, as it could become to get plugged by wax and deposit formed at cold temperatures. This can generate fuel shortage on the common rail and high pressure fuel injectors. Addressing this filter plugging effect, can be crucial for vehicle operability. In order to understand and quantify the cold fuel flow impact on the Diesel fuel filter, a design of experiment has been set-up and achieved.
2014-10-13
Technical Paper
2014-01-2709
Xianjing Li, Liguang Li
Abstract Gasoline Direct Injection (GDI) engines have attracted interest as automotive power-plants because of their potential advantages in down-sizing, fuel efficiency and in emissions reduction. However, GDI engines suffer from elevated unburned hydrocarbon (HC) emissions during start up process, which are sometimes worsened by misfires and partial burns. Moreover, as the engine is cranked to idle speed quickly in HEVs (Hybrid Electric Vehicle), the transients of quick starts are more dramatically than that in traditional vehicle, which challenge the optimization of combustion and emissions. In this study, test bench had been set up to investigate the GDI engine performances for ISG (Integrated Starter and Generator) HEVs during start up process. Based on the test system, cycle-controlled of the fuel injection mass, fuel injection timing and ignition timing can be obtained, as well as the cycle-resolved measurement of the HC concentrations and NO emissions. This paper focus on the detailed effects of coolant temperature, fuel temperature, cranking speed, injection timing and total equivalence ratio on the combustion and emission characteristics of the GDI engine under stratified combustion condition during the engine quick start process cycle by cycle.
2014-10-13
Technical Paper
2014-01-2712
Dai Liu, Hongming Xu, Ramadhas Arumugam Sakunthalai, Jianyi Tian
Abstract Cold start is a critical operating condition for diesel engines because of the pollutant emissions produced by the unstable combustion and non-performance of after-treatment at lower temperatures. In this research investigation, a light-duty turbocharged diesel engine equipped with a common rail injection system was tested on a transient engine testing bed to study the starting process in terms of engine performance and emissions. The engine (including engine coolant, engine oil and fuel) was soaked in a cold cell at −7°C for at least 8 hours before starting the test. The engine operating parameters such as engine speed, air/fuel ratio, and EGR rate were recorded during the tests. Pollutant emissions (Hydrocarbon (HC), NOx, and particles both in mode of nucleation and accumulation) were measured before and after the Diesel Oxidation Catalyst (DOC). The results show that conversion efficiency of NOx was higher during acceleration period at −7°C start than the case of 20°C start.
2014-10-13
Technical Paper
2014-01-2715
Ramadhas Arumugam Sakunthalai, Hongming Xu, Dai Liu, Jianyi Tian, Miroslaw Wyszynski, Jakub Piaszyk
Abstract The cold start performance of a diesel engine has been receiving more attention as the European Commission emission regulations directed to include cold start emissions in the legislative emission driving cycles. The cold start performance of diesel engines is influenced by the ambient temperature conditions, engine design, fuel, lubricant and engine operating conditions. The present research work investigates the effect of cold ambient conditions on the diesel engine's performance and the exhaust emission (gaseous and particulate emissions) characteristics during the cold start and followed by idle. The engine startability and idling tests were carried out on the latest generation of diesel engine in a cold cell at various ambient temperatures ranging between +20°C and −20°C. Higher fuel consumption and peak speed were observed at very cold ambient compared to those at normal ambient during the cold start. The engine exhaust emissions were reached a peak value during the acceleration period of the cold start, and it decreased to maintain the idle speed.
2014-10-13
Technical Paper
2014-01-2714
Cheng Tan, Hongming Xu, He Ma, Jianyi Tian, Akbar Ghafourian
Abstract Automotive engines especially turbocharged diesel engines produce higher level of emissions during transient operation than in steady state. In order to improve understanding of the engine transients and develop advanced technologies to reduce the transient emissions, the engine researchers require accurate data acquisition and appropriate post-processing techniques which are capable of dealing with noise and synchronization issues. Four alternative automated methods namely FFT (Fast Fourier Transform), low-pass, linear and zero-phase filters were implemented on in-cylinder pressure. The data of each individual cycle was compared and analyzed for the suitability of combustion diagnostic. FFT filtering was the best suited method since it eliminated most pressure fluctuation and provided smooth rate of heat release profiles for each cycle. The outputs from the linear and zero-phase filters were close, but zero-phase filter had no phase distortion and eliminated the unwanted fluctuations more effectively.
2014-10-13
Technical Paper
2014-01-2704
Yinbo Cao, Zhongye Xue, Qiqi Miao, Jun Deng, Liguang Li
Abstract Gasoline direct injection (GDI) technology is admitted to be one of the most effective measures to improve the fuel economy for the spark ignition (SI) engines. Homogeneous Charge Compression Ignition (HCCI) combustion has advantages of low fuel consumption and ultra low NOx emissions. But the difficulty in the autoignition control and the narrow operation region inhibit the practical application of this technology. A hybrid combustion mode which combines SI mode and HCCI mode in separated working regions was regarded as a promising technology for HCCI engines. In addition, monitoring and providing feedback to the in-cylinder combustion characteristics is generally considered to be an effective method to improve and to optimize the combustion process. A lot of combustion information is included in the ion current generated by the in-cylinder combustion, and hence the ion current detection technique is considered to be a potential combustion feedback method. A strategy used in the SI/HCCI combustion mode switch based on ion current was established and experimented in a GDI-HCCI engine assisted by negative valve overlap (NVO).
2014-10-13
Technical Paper
2014-01-2707
Brian C. Kaul, Benjamin J. Lawler, Charles E.A. Finney, Michelle L. Edwards, Robert M. Wagner
Abstract Advances in engine controls and sensor technology are making advanced, direct, high-speed control of engine combustion more feasible. Control of combustion rate and phasing in low-temperature combustion regimes and active control of cyclic variability in dilute SI combustion are being pursued in laboratory environments with high-quality data acquisition systems, using metrics calculated from in-cylinder pressure. In order to implement these advanced combustion controls in production, lower-quality data will need to be tolerated even if indicated pressure sensors become available. This paper examines the effects of several data quality issues, including phase shifting (incorrect TDC location), reduced data resolution, pressure pegging errors, and random noise on calculated combustion metrics that are used for control feedback. Symbolic data analysis is an effective technique for identifying underlying patterns in noisy data, and has been applied to cyclic variability of dilute SI combustion, identifying deterministic effects that underlie the stochastic variations that are present.
2014-10-13
Technical Paper
2014-01-2708
Antonino La Rocca, David MacMillan, Paul Shayler, Michael Murphy, Ian Pegg
Abstract Cold idle operation of a modern design light duty diesel engine and the effect of multiple pilot injections on stability were investigated. The investigation was initially carried out experimentally at 1000rpm and at −20°C. Benefits of mixture preparation were initially explored by a heat release analysis. Kiva 3v was then used to model the effect of multiple pilots on in-cylinder mixture distribution. A 60° sector of mesh was used taking advantage of rotational symmetry. The combustion system and injector arrangements mimic the HPCR diesel engine used in the experimental investigation. The CFD analysis covers evolutions from intake valve closing to start of combustion. The number of injections was varied from 1 to 4, but the total fuel injected was kept constant at 17mm3/stroke. Start of main injection timing was fixed at 7.5°BTDC. The experimental study shows that increasing the number of pilots improves stability and leads to fuel preparation resulting in higher initial peak rate of heat release.
2014-10-13
Technical Paper
2014-01-2744
Alessandro Montanaro, Luigi Allocca, Ugo Sorge, Anqi Zhang, Michela Costa
Abstract Diesel sprays from an axially-disposed single-hole injector are studied under both non-vaporizing and vaporizing conditions in a constant-volume vessel. A hybrid shadowgraph/Mie-scattering imaging set-up is used to acquire the liquid and vapor phases of the fuel distribution in a near-simultaneous visualization mode by a high-speed camera (40,000 fps). A diesel injector with k0 factor is used, having the exit-hole diameter of 0.1 mm and the ratio L/d =10. The studies are performed at the injection pressures of 70, 120, and 180 MPa, 25.37 kg/m3 ambient gas density, at the environment temperature of 373, 453 and 900 K. The instantaneous tip penetration of the liquid and vapor phases is extracted from the collected images and processed by a properly assessed software, under the various operating conditions. The AVL FIRE™ code is also used to simulate the spray dynamics. The model is validated on the ground of the collected experimental data. The results dependence upon the cell size of the computational mesh is preliminary discussed.
2014-10-13
Technical Paper
2014-01-2613
Mario Farrugia, Andrew Briffa, Michael Farrugia
Abstract A conversion to LPG of a SI engine that was originally carbureted gasoline is reported in this work. The conversion was implemented on a 1988 Skoda 120L with a 1174cc rear engine. The conversion to run on Liquefied Petroleum Gas (LPG) was carried out using a programmable Engine Control Unit (ECU) that operated a single point fuel injection system. The LPG used was a commercially available mixture of butane and propane. The fuel injection system was designed to operate with the LPG in the liquid state. A circulating pump was used to maintain availability of LPG in liquid state at the inlet to the fuel injector. This made possible the use of similar fuel injection parts as in a gasoline system. Injection of the fuel in the liquid state provided cooling to the intake air as measured during driving of the vehicle and also on chassis dynamometer runs. Engine power output measured on the chassis dynamometer showed equal power between gasoline and LPG around mid RPM of 2500 RPM with a slight decline (4%) in power of the LPG system at 5000 RPM.
2014-10-13
Technical Paper
2014-01-2836
Haichao Fu, Yinhui Wang, Xinyan Li, Shi-Jin Shuai
Abstract An experimental study of particulate matter (PM) emission was conducted on four cars from Chinese market. Three cars were powered by gasoline direct injection (GDI) engines and one car was powered by a port fuel injection (PFI) engine. Particulate mass, number and size distribution were measured based on a chassis dynamometer over new European driving cycle (NEDC). The particulate emission behaviors during cold start and hot start NEDCs were compared to understand how the running conditions influence particulate emission. Three kinds of gasoline with RON 91.9, 94.0 and 97.4 were tested to find the impact of RON on particulate emission. Because of time and facilities constraints, only one cold/hot start NEDC was conducted for every vehicle fueled with every fuel. The test results showed that more particles were emitted during cold start condition (first 200s in NEDC). Compared with cold start NEDC, the particulate mass and number of hot start NEDC decreased by a wide margin. The particulate mass and number reductions of hot start NEDC mainly resulted from ECE cycle sections.
2014-10-13
Technical Paper
2014-01-2860
Ramdas Ugale
Abstract Emerging markets like India is very cost sensitive for small engines like motorcycle. Capacitive discharge Ignition (CDI) with carburetor is popular low cost solution with good engine performance. CDI system accumulates charge inside the ignition capacitor, until a point at which a signal allows to release discharge of the stored charge to the spark plug through high tension coil. This paper will focus on single spark digital two teeth DC CDI solution and below design challenges with two sparks. 1 Higher power dissipation in step up fly back converter2 Need higher CPU speed, flash size and restrictions on engine map profile for advance angles This paper will elaborate above problems and their solutions with test results for optimizing solution cost and achieve performance. Solutions include, exploring 8 bit microcontroller peripherals usage and smart software to boost MCU performance for engine dynamic conditions and to achieve lower losses in flyback converter.
2014-10-13
Technical Paper
2014-01-2899
Lukasz Grabowski, Konrad Pietrykowski, Michal Geca, Grzegorz Baranski
Abstract City buses are equipped with an increasing number of electrical devices that are designed to improve the driver work and increase passengers' comfort. The alternator must therefore meet the requirements of increased levels of electric energy demand. In this paper, the focus is set on the amount of chemical energy in the fuel transformed into electric energy by the alternator, especially in the case of urban transport. The article presents the results of operating states of the alternator in the city bus while driving. During the study waveforms of rotational speed and load current of power generation system were recorded. The results of measurements made it possible to draw histograms showing the share of working time in different points of the alternator work. Only about 43% of the total working time corresponds to the bus stop and the operation of the idle speed of the alternator 2250 rpm. The remaining time corresponds to the average speed about 4200 rpm and does not exceed 6600 rpm.
2014-10-13
Technical Paper
2014-01-2896
Krzysztof Jan Siczek
Abstract Conditions of the bacterial battery have been presented in the article. The models of different design configurations of bacterial battery and its assembly with electric circuit has been elaborated. The obtained values of voltage and currents obtained in such models has been compared with the case of similar circuit using lithium-ion battery and presented in the paper.
2014-10-13
Technical Paper
2014-01-2894
Boru Jia, Zhengxing Zuo, Huihua Feng, Guohong Tian, A. P. Roskilly
Abstract The free-piston engine generator (FPEG) is a novel type of energy conversion device; it integrates a two stroke combustion engine and a linear electric machine into a single unit. As an alternative to conventional engines, the FPEG is a promising power generation system due to its simplicity and high thermal efficiency and has attracted considerable research interests recently. This paper presents the development for a spark-ignited free-piston engine generator prototype, and the design of major sub-systems is introduced. The electrical linear machine is operated as a motor to start the engine and switched to a generator after successful ignition. Ignition is one of the most crucial problems for the generating process, thus a unique control sub-system to generate ignition signals at the correct ignition timing based on the piston position was completed. Then experiments of the starting process were carried out with the prototype. The results indicate that with a fixed motor force of 110N, the maximum in-cylinder gas pressure can reach 12 bar and the compression ratio can reach 8:1.
2014-10-13
Technical Paper
2014-01-2901
Albert Albers, Kevin Matros, Matthias Behrendt, Johannes Henschel, Heidelinde Holzer, Wolfram Bohne
The requirement of the start of the internal combustion engine (ICE) not only at vehicle standstill is new for full hybrid electric vehicles in comparison to conventional vehicles. However, the customer will not accept any deterioration with respect to dynamics and comfort. ICE-starting-systems and -strategies have to be designed to meet those demands. Within this research, a method was developed which allows a reproducible maneuver-based analysis of ICE-starts. In the first step, a maneuver catalogue including a customer-oriented maneuver program with appropriate analysis criteria was defined. Afterwards, the maneuvers were implemented and verified in a special test bench environment. Based on the method, two sample hybrid vehicles were benchmarked according to the maneuver catalogue. The benchmarking results demonstrate important dependencies between the criteria-based assessment of ICE-starts and the embedded ICE-starting-system and -strategy. Those findings led to recommendations regarding the selection of suitable starting-systems and the design of the starting-strategy.
2014-10-13
Technical Paper
2014-01-2748
Dehao Ju, Tingting Zhang, Jin Xiao, Zhen Huang
Abstract In order to quantitatively investigate the macroscopic characteristics of flash-boiling atomization, the spray injected through a plain-orifice nozzle under atmospheric conditions was directly imaged and analyzed by the multi-threshold algorithm. The spray images were acquired at various times after the start of actuation using a high-speed visualization system. The light intensity level of images implies the local relative mass concentration of droplets in the spray. Transient contour plots of spray images at various thresholds were analyzed and compared with turbulent round jets of diesel. A new term, transient continuous cone angle, was defined to characterize the flash-boiling spray. The relative mass concentration distributions and continuous cone angles of the sprays during the start, development and end periods of the atomization were discussed for two different sprays. The grayscale levels of sprays in the outer and end regions of the sprays were lower compared to those in the center regions, because the droplets at the outer and end regions were well-atomized by the volatile nature of the material and the friction between the injected droplets and the surrounding gas.
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