Search Results

Direct fuel injection is becoming mandatory in two-stroke S.I. engines, since it prevents one of the major problems of these engines, that is fuel loss from the exhaust port. Another important problem is combustion irregularity at light loads, due to excessive presence of residual gas in the charge, and can be solved by charge stratification. High-pressure liquid fuel injection is able to control the mixing process inside the cylinder for getting either stratified charge at partial loads or quasi-stoichiometric conditions, as it is required at full load. This paper shows the development of this solution for a small engine for moped and light scooter, using numeric and experimental tools. In order to obtain the best charge characteristics at every load and engine speed, different combustion chambers have been conceived and studied, examining the effects of combustion chamber geometry, together with injector position and injection timing

This paper presents 1D engine simulation used for engine control strategy optimization for a twin-scroll turbocharged gasoline direct injection 2.0 L engine with twin camphaser. The results show good agreement of the engine model behavior with testbed acquisitions for a large amount of steady state set points and under transient operating conditions. The presented method demonstrates that a 1D engine code represents a useful and efficient tool during all steps of the engine control development process from design to real-time for such an advanced engine technology.

Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumption and NOx emissions. Currently, CAI combustion is constrained at part load operation conditions because of misfire at low load and knocking combustion at high load, and the lack of effective means to control the combustion process. Extending its operating range including high load boundary towards full load and low load boundary towards idle in order to allow the CAI engine to meet the demand of whole vehicle driving cycles, has become one of the key issues facing the industrialisation of CAI/HCCI technology. Furthermore, this combustion mode should be compatible with different fuels, and can switch back to conventional spark ignition operation when necessary. In this paper, the CAI operation is demonstrated on a 2-stroke gasoline direct injection (GDI) engine equipped with a poppet valve train.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

Wing panels for Boeing's new 777 airplane are assembled using fastening machines called Wing Fastener Systems (WFS). Compared to the wing riveting machines currently used to squeeze rivets for other airplane models, the 777 WFS provides significantly more features in that it also installs two part fasteners, collects process data for Statistical Process Control analysis, plus other functions. Historically, new operators for wing riveting machines have needed six months of on-the-job training to achieve basic qualification. Because of the increased functionality of the 777 WFS, an eight to nine month O.J.T. requirement was anticipated. Training requirements were further compounded by our need for up to thirty qualified operators in a relatively short time frame and a maintenance staff thoroughly trained in the new control architecture. Boeing's response to this challenge was to use simulation methods similar to those used to train pilots for our customer airlines.

During the production controller and software development process, one critical step is the controller and software verification. There are various ways to perform this verification. One of the commonly used methods is to utilize an HIL (hardware-in-the-loop) test bench to emulate powertrain hardware for development and validation of powertrain controllers and software. A key piece of an HIL bench is the plant dynamics model used to emulate the external environment of a modern controller, such as engine (ECM), transmission (TCM) or powertrain controller (PCM), so that the algorithms and their software implementation can be exercised to confirm the desired results. This paper presents a 6-speed automatic transmission plant dynamics model development for hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software. The modeling method, model validation, and application in an HIL test environment are described in details.

The military aviation services pay a phenomenal price due to turbine engine stall. Several of the major factors which comprise a substantial portion of the total price are presented. Included are weapon system development time, operational limitations, field maintenance problems, overhaul costs and accident rates. Also presented, in a general fashion, are several technical approaches to the solution of turbine engine stall. Fundamental research and orderly development of basic engine components, power control systems, and airframe and installation factors are discussed. Emphasis is placed on the need for tighter control of production tolerances and the requirement for united efforts in the integration of components into a complete system.

This paper presents a hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software, with a focus on a closed-loop vehicle drive-train model incorporating a detailed automatic transmission plant dynamics model developed for certain applications. Specifically, this paper presents the closed-loop integration of a 6-speed automatic transmission model developed for our HIL transmission controller and algorithm test bench (Opal-RT TestDrive based). The model validation, integration and its application in an HIL test environment are described in details.

This paper discusses a design of Internet-based remote manufacturing system, which would help a global company to centralize its production, to control and to monitor the operation from the remote sites. In our design, we describe our system in two main categories, which are the design system and the manufacturing system. In the design system, we use the Internet-based client-server architecture to allow multiple clients to design products collaboratively and simultaneously. After the design is finished, it will be sent to the manufacturing system. At this stage, the clients can control and monitor the process from geographically distributed locations via the Internet.

The classical use for zinc alloy die castings for plated trim and non-structural applications is being supplemented with new engineered applications. New alloys such as ZA-27 offer higher strengths than #3, which when combined with cost effective, net shape capability of the die casting process provide new opportunities in automotive component design. A systematic design strategy must, however, become part of the product design process. This strategy, by evaluating mechanical and physical properties of the material against use requirements, offers the best methodology for new and replacement applications.

A digital memory fuel control unit has been developed for otto cycle engines which enables low pollution exhaust emissions to be achieved, coupled with good drivability and mechanical performance. The unit has been tested on a Triumph 2.5 PI vehicle, and the practical results achieved fall just short of the requirements of the 1975 federal and California legislation. The electronic controller receives signals relating to the engine's instantaneous operating conditions and, by reference to its digital memory, computes the optimum fuel required. The capacity of the controller's memory is effectively increased by an interpolation technique. The controller operates as an on-line process control computer, of cigar box dimensions, which is able to exist in the arduous automotive environment.

Tubular hydroforming is a novel process that has recently gained much attention due to its cost-effective application in the automotive industry. Hydroformed automotive parts have high strength to weight ratio and have good repeatability with high dimensional accuracy. At this time, there is little experience in modeling the hydroforming process to better understand its application and researchers have tried using stamping simulation software to analyze the process. Unlike conventional sheet stamping which is a displacement driven process, tubular hydroforming is a force driven process and its success is governed by the nature of internal pressurization. Hence, a new three-dimensional finite element model using a computationally efficient 6-noded shell element has been developed. A simple pressure prediction model has been developed and integrated into the formulation for effective control of the process.

Presented in this paper is a framework for the implementation of a robotic percussive riveting system, a new robot application for aircraft assembly. It is shown here that a successful robot application to the automation of a process requires in-depth research of the process and the interaction with the robot. For this purpose, a process planning-driven approach is proposed to guide a robot application research. A typical process planning will involve a list of key considerations including: process sequence, process parameters, process tooling, and process control. Through this list, a number of key research issues are identified for robotic percussive riveting, such as rivet pattern planning, riveting time determination, riveting tooling design and rivet insertion control. The detailed research on these issues has effectively created know-how for the successful implementation of our robotic percussive riveting system.

To reduce pollutant emission and increase performance of vehicles, the first step is before combustion, to understand and then to control the mixing process of fuel with air. It is well known that injection inside the combustion chamber is the key phenomenon. This paper focuses on the spray morphology in engine like conditions. A complete system has been built based on an optical diagnostic to visualize the sprays under nitrogen back pressure chamber. To measure spray parameters from the recorded images an entropic thresholding has been implemented. An automatic algorithm computes the spray tip penetration and cone angle from the rough images with a correction of the measurements depending on the hole injection angle.

The demonstrated architectural model and associated graphical techniques defined herein were developed to provide a simple method of visualizing the general functional operation or behavior of a Distributed Embedded System with a strong emphasis on representing system time characteristics.