Showing papers on "Vehicle engineering published in 2012"

Aircraft Design: A Systems Engineering Approach

Abstract: Presenting in one volume the methodologies behind aircraft design, this book covers the components and the issues affected by design procedures. The basic topics that are essential to the process, such as aerodynamics, flight stability and control, aero-structure, and aircraft performance are reviewed in various chapters where required. Based on these fundamentals and design requirements, the author explains the design process in a holistic manner to emphasise the integration of the individual components into the overall design. Throughout the book the various design options are considered and weighed against each other, to give readers a practical understanding of the process overall.

Rolling resistance model, fuel consumption model and the traffic energy saving potential from changed road surface conditions

Abstract: For att uppskatta hur trafikenergin paverkas av forbattrad vagytestandard behovs foljande:• rullmotstand som funktion av vagytans tillstand• alla ovriga fardmotstand• bransleforbrukning (Fc) som fu

Towards a unified framework using CPACS for geometry management in aircraft design

Abstract: The performance requirements for the next generations of airliners are stringent and require invention and design of unconventional configurations departing from the classical Cayley functional dec

The Use of Potentially Critical Materials in Passenger Cars

Abstract: High metal prices, increased demand for potentially critical minerals from growing economies, geographically concentrated production and environmentally unsustainable mining practices (Alonso, et al., 2012) have received increased political, research and business interest. The demand from competing technologies such as wind power turbines, nuclear power plants, solar panels, super alloys and technologies used in passenger cars such as catalysts, glass, information and communications technologies (ICT’s), flat panel displays, permanent magnets and electronic equipment is fast growing (European Commission, 2010). This, along with the expected material needs of increased electrification of passenger cars, requires the automotive industry to monitor the use of potentially critical materials. In order to be able to plan for the future and develop sustainable environmental strategies for potentially critical materials, it is first of all important for the manufacturer to know if and if so, how much of the materials they use in their products. With this background, this thesis was initiated by the Volvo Car Corporation (VCC) and the division of Environmental System Analysis at Chalmers University of Technology. The purpose of the thesis is to provide knowledge on the use of potentially critical materials in passenger cars. This involves screening relevant literature about critical materials in order to find materials to study and then analyzing which type of car parts that contains these materials. The use of the materials should be quantified and factors influencing the use should be analyzed. Data was to be gathered from the International Material Data System (IMDS) and the usability of the system was to be evaluated. The thesis contains a material mapping of the use of 31 potentially critical materials in 4 different car models. The conclusions include:  The largest quantities of the material mapped can be found in metallurgical, catalytic and electrical and electronic applications.  Electrification of the powertrain increases the use of mainly neodymium, dysprosium, copper, samarium, silver, terbium, manganese and lithium but also palladium and platinum.  Increased equipment level increase the use of mainly neodymium, dysprosium, copper, gallium, lithium, praseodymium and tantalum but also niobium, palladium and platinum.  Increased size of the car could not be shown to directly increase the use. The reason for why the latter could not be shown is believed to be a consequence of other factors, such as year of design.  The choice of catalytic exhaust treatment system is determined to influence the use of cerium, lanthanum, palladium and platinum.  The IMDS offers the opportunity to access and create comprehensive and detailed information of the material content in vehicles. However, the system relies on the suppliers’ own declaration of data, with reporting time lags and only controlled by the automaker OEM’s by random sampling.

Advancing the Limits of Dual Fuel Combustion

Abstract: There is a growing interest in alternative transport fuels. There are two underlying reasons for this interest; the desire to decrease the environmental impact of transports and the need to compens ...

Flight trajectory optimization for an efficient air transportation system

Abstract: An efficient, reliable and futuristic Air Transportation System (ATS) is the key to handle the anticipated rapid changes in the aviation industry over the next few decades. Trajectory Based Operations (TBO) could be considered as one of the most significant solutions to cater for these problems. This paper discusses the development of a 4D optimal flight trajectory based on aircraft performance, weather forecasts, Air Traffic Control (ATC) database and aircraft operational data. Dynamic Programming is utilized in the optimization process for its qualities of avoiding iterative calculations, predicting the required amount of calculations and feasibility of applying inequality constraint conditions. Optimal flight trajectories were generated for a single aircraft for its climb, cruise and descent phases in a provided 4D grid platform based on a busy domestic flight route, between Tokyo (Haneda) and Fukuoka. Flight data were recorded on a commercial GPS data logger inside an airliner cabin and used to compare with optimum solutions obtained from the model. Consumed fuel consumption and flight time were evaluated to understand the benefits gained by the optimization.

Improving Turbocharged Engine Simulation by Including Heat Transfer in the Turbocharger

Abstract: Engine simulation based on one-dimensional gas dynamics is well suited for integration of all aspects arising in engine and power-train developments. Commonly used turbocharger performance maps in ...

An approach in prediction of failure in resistance spot welded aluminum 6061-T6 under quasi-static tensile test

Abstract: The aim of this article is to predict the failure load in resistance spot welded aluminum 661-T6 sheets with 2 mm thickness under quasi-static tensile test. Various welding parameters, e.g. welding ...

Survey on fault-tolerant vehicle design

Abstract: Fault-tolerant vehicle design is an emerging inter-disciplinary research domain, which is of increased importance due to the electrification of automotive systems. The goal of fault-tolerant systems is to handle occuring faults under operational condition and enable the driver to get to a safe stop. This paper presents results from an extended survey on fault-tolerant vehicle design. It aims to provide a holistic view on the fault-tolerant aspects of a vehicular system. An overview of fault-tolerant systems in general and their design premises is given as well as the specific aspects related to automotive applications. The paper highlights recent and prospective development of vehicle motion control with integrated chassis control and passive and active fault-tolerant control. Also, fault detection and diagnosis methods are briefly described. The shift on control level of vehicles will be accompanied by basic structural changes within the network architecture. Control architecture as well as communication protocols and topologies are adapted to comply with the electrified automotive systems. Finally, the role of regulations and international standardization to enable fault-tolerant vehicle design is taken into consideration.

Engineering methods applied to an unmanned combat air vehicle configuration

Abstract: Engineering methods provide fast and economic predictions of the aerodynamic characteristics of complex flight vehicles. This paper investigates the application of three specific engineering method ...

Operational Guidance with Respect to Pure Loss of Stability and Parametric Rolling

Abstract: This paper reviews two previously presented simplified methods for assessment of pure loss of stability and parametric rolling based on linear signal theory. The methods are evaluated in relation to full-scale incidents and time-domain simulations. Underlying assumptions and tuning of the critical levels in the simplified methods with reference to time-domain simulations is discussed. Given proper tuning the methods are concluded to provide a feasible basis for ship specific on-board operational guidance.

Divided Exhaust Period on Heavy-Duty Diesel Engines

Abstract: Divided Exhaust Period (DEP) has previously been studied on SI engines while results fromHD diesels are scarcer. In this paper the DEP concept has been numerically simulated on two HD dieselengines ...

Identification for Automotive Systems

Abstract: From the Contents: Challenges and Opportunities for Identification Methods in Automotive Systems.- A Desired Modelling Environment for Automotive Powetrain Controls.- An Overview on System Identification Problems in Vehicle Chassis Control.- Linear Parameter-varying System Identification: The Subspace Approach.- A Tutorial on Numerical Methods for State and Parameter Estimation in Nonlinear Dynamic Systems.- Using Genetic Programming in Nonlinear Model Identification.- Markov Chain Modelling and On-board Identification for Automotive Vehicles.

Turbocharged SI-Engine Simulation With Cold and Hot-Measured Turbocharger Performance Maps

Abstract: Heat transfer within the turbocharger is an issue in engine simulation based on zero and one-dimensional gas dynamics. Turbocharged engine simulation is often done without taking into account the h ...

Pure electric vehicle driving system parameter matching in motor higher efficiency interval

Abstract: This paper describes the mode matching design of powertrain based on the case for electric vehicle from the engineering point of view and the real vehicle testing. It includes the choice of motor, drive the design, choice of battery power and so on. It is the goal for improving efficiency of electric vehicle for the design of transmission scheme. By output characteristics on the test drive motor, the change of accelerator pedal position sensor signal voltage variation about speed and motor efficiency is obtained. The design will be used to determine the transmission shift control strategy in order to ensure high efficiency motor area when the motor always works to achieve the objective of increasing driving range. In the design process the performance simulation is by ADVISOR. The performance of matching design is tested by experiments.

Variational analysis and aerospace engineering: mathematical challenges for aerospace design

Abstract: PrandtlPlane Propelled with Liquid Hydrogen: A Preliminary Study.- Aeroacousto-elastic modelling for response analysis of helicopter rotors.- Numerical Investigation on Aeroelastic and Aeroacoustic Responses.- Crack Extension Energy Rate and Energetic Approaches in Elastic-Plastic Fracture Mechanics.-A Criterion for Ductile Crack Growth based on the Energy-Momentum Tensor.- Optimal location of support points in the Kirchhoff plate.- A Code for Shape Generation and Aerodynamic Design of Aircraft.- Design of solar powered unmanned biplanes for HALE missions.- The PrandtlPlane configuration: overview on possible applications to civil aviation.- The lifting system of a PrandtlPlane Part 1: Design and analysis of a light alloy structural solution.- The Lifting System of a PrandtlPlane Part 2: Preliminary Study on Flutter Characteristics.- The lifting system of a PrandtlPlane Part 3: Structures made in composites.- Elastic structures in adhesion interaction.- Conceptual design of a very large PrandtlPlane freighter.- Mesh Adaptivity and Optimal Shape Design for Aerospace.- Numerical simulation of sailing boats: dynamics, FSI, and shape optimization.- On the Way to ACARE 2020 and Beyond. -Design problems of anisotropic structures: some recent results.- The warlike interest in impact theories.- Flight mechanics modeling of the Prandtl plane for conceptual and preliminary design.

Evaluation of Safety Distance in Vehicle Platoons by Combined Braking and Steering

Abstract: Platooning is a way to increase the traffic flow and capacity on roads to handle the upcoming problems of traffic congestion and exhaust emissions. The aim with this work is to evaluate if the safe ...

Control strategy of hybrid electric vehicle based on driving intention identification

Abstract: The parameters of driving intention identification were defined and the membership functions of the defined parameters and the fuzzy inference rules were established.The driving intentions were identified by fuzzy inference.The hybrid electric vehicle control strategy was formulated based on the driving intention identification results and its simulations were done.The simulation results show that the fuzzy inference system identifies well the driving intentions and the control strategy based on the driving intention identification improves the fuel economy of the hybrid electric vehicle.

Fault-Tolerant Control of Electric Vehicles with In-Wheel Motors through Tyre-Force Allocation

Abstract: This paper presents a fault handling strategy for electric vehicles with in-wheel motors The ap-plied control algorithm is based on tyre-force allocation One complex tyre-force allocation meth-od

Simulation of Vehicle-Overhead Power System Interaction on Electric Roads

Abstract: Due to the upcoming lack of oil and the environmental problems that conventional internal combustion engines are causing, electric vehicles have gained a growing interest during recent years. One s ...

On-Engine Turbocharger Performance Considering Heat Transfer

Abstract: Heat transfer plays an important role in affecting an on-engine turbocharger performance. However, it is normally not taken into account for turbocharged engine simulations. Generally, an engine si ...

Development of Velocity planner for a Racing driver model

Abstract: Testing a vehicle’s limit handling capabilities can provide a valuable insight into analysing and hence developing new vehicle designs. A driver model is a convenient tool used particularly in full vehicle simulations and if it is capable of simulating driving on the limit with minimum user input then it becomes all the more effective. There is inadequate information found in literature concerning the simulation of limit handling capability of a vehicle using a driver model. There was a requirement to improve an existing driver model in Modelon AB’s Vehicle dynamics library (VDL), so that it would enable the user find the limits of handling of a vehicle. This also had to be accomplished with minimum user input and without a priori information of the entire track. Furthermore, the vehicle model should be driven on the pre-defined path on the road accurately. Hence the speed calculation has to be accurate, capable of triggering braking, whenever required to successfully maintain the trajectory of the vehicle on the given path. The targets of lateral and longitudinal acceleration/deceleration of the vehicle model were the only input specified by the user. The complete driver model was then to be used in closed loop driving manoeuvre simulations on a 2-D road. The velocity planning block, developed in this thesis, calculates the vehicle speed based on user inputs. It also utilises a limited look-ahead preview of the track and ensures that the vehicle model is pushed to the boundaries of these specified targets while at the same time maintaining the pre-defined trajectory. The tests are conducted on three different tracks; A circular track with constant radius, J-turn and an extended chicane Two strategies were employed to solve the problem. First, a single-point look-ahead preview, where information about one point of the upcoming road curvature is known, is incorporated into the driver model. Later, in order to make the solution more robust, a multi-point preview is implemented. The velocity profile calculated was found to push the car to the specified targets and the velocity tracking was performed to a satisfactory level. The vehicle model accurately followed the pre-defined vehicle trajectory without a priori information of the track, and in the case of single-point preview strategy, the look-ahead distance required almost no fine tuning of the preview distance for the three tracks the model was tested on.

Modular machinery arrangement and its impact in early-stage naval electric ship design

Abstract: Electrical power demands for naval surface combatants are projected to rise with the development of increasingly complex and power intensive combat systems. This trend also coincides with the need of achieving maximum fuel efficiency at both high and low hull speeds. A proposed solution to meet current and future energy needs of conventionally powered naval surface combatants is through the use of an Integrated Power System (IPS), which is seen as the next evolution in naval ship design. Unfortunately, historically-based ship design process models and parametrics cannot accommodate new-concept designs that are not incremental changes to previous practice. Additionally, integrating IPS with the next generation of ship designs is also synonymous with the desire of conducting system-level tradeoffs early within the ship design process. In an effort to enhance the relationship between new-concept designs and historically-based ship design processes, this thesis focuses on a novel approach of incorporating IPS at the earliest stage of the design process as part of assessing system-level tradeoffs early. This thesis describes a methodology for the system design and arrangement of an IPS machinery plant based on an objective of meeting a desired power generation level, effectively introducing a power constraint at the start of the design process. In conjunction with the methodology development, a hierarchical process and design tool for integration with Graphics Research Corporation's (GRC) naval architecture software suite, Paramarine, is also produced to assist in rapid development and evaluation of various IPS arrangements. The result of this process, through several case studies, provides insight into equipment selection philosophy, the initial sizing of the ship's machinery box, and the initial definition of electrical zones. Lastly, the developed tool is also used to aid in the creation of "design banks," allowing the naval architect to manage weight, power, and volume at the beginning of the ship design process; therefore, supporting early system-level tradeoffs for new-concept designs. Thesis Supervisor: Chryssostomos Chryssostomidis Title: Doherty Professor of Ocean Science and Engineering Professor of Mechanical and Ocean Engineering

Experiments and analysis of the dual-overrunning clutches electro-mechanical regenerative damper prototype

Abstract: Based on previous analysis of the dual-overrunning clutches electro-mechanical regenerative damper concept,a prototype damper is designed and built for laboratory experiments.The frequency and damping response features are tested under harmonic excitation.Prototype experiment results verify the feasibility of the damper design;meanwhile,the method to achieve high-low semi-active damping in a passive manner is testified.This study may provide the guidance for further investigating the structure of dual-overrunning clutches.

Risk-based ship security analysis: an approach based on civilian and military methods

Abstract: The demands on maritime operations today are increasingly higher in terms of control, efficiency and cost. The margins for accidents and security incidents are therefore decreasing. In the area of ...

Vibration mitigation for High Speed Craft

Abstract: The crew of small, high-speed marine craft (HSC) is exposed to high levels of vibrations and shocks that can imply risks for adverse health effects. The working environment needs to be improved by ...

Acoustic Characterization of Turbochargers and Pipe Terminations

Abstract: In search for quieter engines there is a need for a better understanding of the acoustic properties of engine intake and exhaust system components. Besides mufflers which have the purpose of reduci ...