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Viewing 1 to 30 of 21965
2017-10-08
Technical Paper
2017-01-2198
Zhihong Li, Guoxiu Li, Lan Wang, Hongmeng Li, Jie Wang, Haizhou Guo, Shuangyi He
The electromagnetic valve driving mechanism is the significant equipment, which plays a vital role in the unit pump injection system; therefore, the performance of the electromagnetic valve directly influences the function of the control system. Based on the operation conditions of the unit pump injection system, a steady electromagnetic valve model was modified to study the influence factors of electromagnetic force and the best combination to get the maximum electromagnetic force. The validation model was verified by experiment. The effects of some crucial parameters upon the electromagnetic force were investigated in the present paper, (including working airspace, magnetic pole’s cross-sectional area, coil position, coil turn, the armature thickness). The result shows that the electromagnetic force of the solenoid valve enhanced with the increasing driving current and reduced with the decreasing of working condition.
2017-10-08
Technical Paper
2017-01-2309
hua Wen, Shuaishuai Liang, Peng Chen, Guangjun Jiang
In this paper, a contrast experiment has been carried out for discussing the phenomenon of fuel dripping at the end of injection by using the different nozzles with varied materials. The experiment results show that the nozzle deformation has an important effect on the fuel dripping at the end of injection. The duration of the fuel shut-off process with the steel nozzle which producing smaller deformation is shorter than the polymethyl methacrylate nozzle. The mass of fuel dripping with the steel nozzle is less. For implementing a deep analysis on the experimental phenomenon about the fuel dripping with the polymethyl methacrylate nozzle, a three dimensional numerical simulation research was carried out for analyzing the influence of fuel flow inside nozzle on the solid deformation and stress distribution of the nozzle by using Fluid-Structure-Interaction method.
2017-10-08
Technical Paper
2017-01-2226
Edward S. Richardson, Bruno S. Soriano, Mathew Middleton, Michael J. Gill
Cylinder deactivation enables improvements in fuel economy in spark-ignition engines by reducing pumping losses during part load operation. The efficiency benefits of a new intake valve system that enables cycle-by-cycle deactivation of different cylinders is investigated in this study. The system minimises the need for throttling by varying the fraction of strokes that are deactivated in order to vary engine output. The intake valve system involves two intake valves in series, with a fast solenoid-actuated valve upstream of a conventional cam-actuated intake valve. Compared to conventional cam-actuated valves, the new valve system has potential to achieve very rapid closing rates with a high degree of flexibility in respect of the timing of inlet valve closure. The fuel economy benefits provided by a number of valve control strategies are evaluated using a one-dimensional modelling approach, considering a vehicle following the New European Drive Cycle.
2017-10-08
Technical Paper
2017-01-2423
Xiaoming Ye, Yan Fu, Wei Li, Yuze Jiang, Shixin Zhu
Crankshaft main bearing is the key component of internal combustion engine(ICE), which is used to support the movement of crank link mechanism and realize the conversion of energy. The lubrication performances and wear life of the crankshaft main bearing will directly affect the working efficiency and reliability of ICE. Therefore, it is very important to study the lubrication performances of the crankshaft main bearings. In this paper, a 16V marine diesel engine was studied as the research object. Based on the AVL-Designer software platform, the crank link mechanism dynamics model and the main bearing fluid lubrication numerical model were established. Numerical analysis was carried out on the lubrication performances of the crankshaft main bearings under different rotating speed conditions. The stress state, the maximum oil film pressure, the minimum oil film thickness, the axis orbit and other lubrication performance parameters were obtained from the results.
2017-10-08
Technical Paper
2017-01-2427
Suresh Kumar Kandreegula, Rahul Jain, Shivdayal Prasad
Automotive vehicle includes various systems like engine, transmission, exhaust, air intake, cooling and many more systems. No doubt the performance of individual system depends upon their core design. But for performance, the system needs to be fastened properly. In automotive, most of the joints used fasteners which helps in serviceability of the components. There are more than thousands of fasteners used in the vehicle. At various locations, we found issue of bolt loosening and because of this the design intent performance is not met by the system. During product development of ECS (Engine cooling system), various issues reported to loosening the bolt. The pre-mature failure of bolt loosening, increases the interest in young engineers for understanding the behavior of fastener in vehicle running conditions. This paper focuses on the design of wedge shape of washer to avoid bolt loosening.
2017-09-28 ...
  • September 28-29, 2017 (8:30 a.m. - 4:30 p.m.) - Ft. Worth, Texas
Training / Education Classroom Seminars
The avionics hardware industry world-wide is now commonly required to follow DO-254 Design Assurance Guidance for Airborne Electronic Hardware for literally all phases of development: Safety, Requirements, Design, Logic Implementation, V&V, Quality Assurance, etc. The DO-254 standard is a companion to the software DO-178B standard; however, there are many differences between hardware and software which must be understood. This basic course introduces the intent of the DO-254 standard for commercial avionics hardware development.
2017-09-28 ...
  • September 28, 2017 (8:30 a.m. - 4:30 p.m.) - Ft. Worth, Texas
Training / Education Classroom Seminars
The challenges associated with using composites as a replacement for aluminum reside primarily in the complex manufacturing processes and technologies for fabricating composite parts. The high cost of composites material and its manufacturing complexity have been inhibitors to the wide transfer of this technology to the non-aerospace market. The search for solutions to high manufacturing costs and efficient manufacturing processes have resulted in intense research by government, aerospace industry companies, and space agencies worldwide.
2017-09-19
Technical Paper
2017-01-2098
Didier Friot, Loic Meiffre, Christophe Vandaele
With air traffic demand constantly increasing and several years of aircraft production in backlog, major Aircraft manufacturers are now shifting focus to improving assembly process efficiency. One of the most promising solutions, known as “One Side Assembly”, aims to perform the whole assembly sequence from one side of the structure (drilling, temporary fastener installation and removal, blind fastener installation, assembly control) and with high level of integrated automation. A one-sided, or blind, fastener that is capable of matching the performance of current two sided structural fasteners while meeting volume and cost objectives can be a major driver for assembly process efficiency improvements. To achieve a blind fastener assembly capable of both fully automated and manual installations while providing robust cycle times and assembly cost reductions is full of challenges.
2017-09-12
Event
2017-09-04
Technical Paper
2017-24-0073
Carlo Beatrice, Giacomo Belgiorno, Gabriele Di Blasio, Ezio Mancaruso, Luigi Sequino, Bianca Maria Vaglieco
Technologies for direct injection of fuel in compression ignition engines are in continuous development in order to get an increasingly high injection pressure. One of the most investigated component of this system is the injector; in particular, main attention is given to the nozzles characteristics as diameter, number, angle, internal shape. The reduction of nozzle hole diameter seems the simplest way to increase the fuel velocity and to promote the atomization process. On the other hand, the number of the holes must increase to keep the desired mass flow. On this basis, a new logic has been applied for the development of the next generation of injectors. The tendency to increase the nozzle number and to reduce the diameter has led to the replacement of the nozzle with a circular plate that moves vertically. The plate motion allows to obtain a cylindrical surface for the delivery of the fuel on 360° degrees; while the plate lift is calibrated to obtain the desired fuel mass flow.
2017-09-04
Technical Paper
2017-24-0101
Pedro Marti-Aldaravi, Kaushik Saha, Jaime Gimeno, Sibendu Som
Abstract Actual combustion strategies in internal combustion engines rely on fast and accurate injection systems to be successful. One of the injector designs that has shown good performance over the past years is the direct-acting piezoelectric. This system allows precise control of the injector needle position and hence the injected mass flow rate. Therefore, understanding how nozzle flow characteristics change as function of needle dynamics helps to choose the best lift law in terms of delivered fuel for a determined combustion strategy. Computational fluid dynamics is a useful tool for this task. In this work, nozzle flow of a prototype direct-acting piezoelectric has been simulated by using CONVERGE. Unsteady Reynolds-Averaged Navier-Stokes approach is used to take into account the turbulence. Results are compared with experiments in terms of mass flow rate. The nozzle geometry and needle lift profiles were obtained by means of X-rays in previous works.
2017-09-04
Technical Paper
2017-24-0108
Alessandro Montanaro, Marianna Migliaccio, Luigi Allocca, Carlo Beatrice, Valentina Fraioli, Roberto Ianniello
Abstract In the present paper, a new concept of open nozzle spray was investigated as possible application for compression ignition engines. The study concerns an experimental and numerical characterization of a spray generated through a prototype high-pressure hollow-cone nozzle (HCN). The experimental description of the injection process was carried out under evaporative and non-evaporative conditions injecting the fuel in a constant-volume combustion vessel controlled in pressure and temperature in order to measure the spatial and temporal fuel pattern at engine-like gas densities. OpenFOAM libraries in the lib-ICE version of the numerical code were employed for simulating the spray dynamics after a first validation phase based on the experimental data. Results show a typical spray structure of the outward-opening nozzle with the overall fluid-dynamic arrangement having a good fuel distribution along the hollow-cone geometry but showing a reduced spatial penetration.
2017-09-04
Technical Paper
2017-24-0111
Heechang Oh, JuHun Lee, Seungkook Han, Chansoo Park, Choongsik Bae, Jungho Lee, In Keun Seo, Sung Jae Kim
Abstract In this study, the effect of the nozzle tip geometry on the nozzle tip wetting and particulate emissions was investigated. Various designs for the injector nozzle hole were newly developed for this study, focusing on the step hole geometry to reduce the nozzle tip wetting. The laser induced fluorescence technique was applied to evaluate the fuel wetting on the nozzle tip. A vehicle test and an emissions measurement in a Chassi-Dynamo were performed to investigate the particulate emission characteristics for injector nozzle designs. In addition, the in-cylinder combustion light signal measurement by the optical fiber sensor was conducted to observe diffusion combustion behavior during the vehicle test. Results showed that the step hole surface area is strongly related to nozzle tip wetting and particulate emissions characteristics.
Viewing 1 to 30 of 21965

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