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This paper reports on the cold (below 20°C coolant temperature) characterisation of a Jaguar 4.2 litre supercharged engine using a model based design of experiment approach. Engine responses were modelled and optimised to improve emissions performance under cold operating conditions. Key modelling and optimisation techniques are discussed, and a selection of results is presented.

CFD simulations were first performed on the inlet manifold of the 2004 University of Sydney (USYD) FSAE competition car. For years prior to 2004, the FSAE team used classical techniques such as Helmholtz method to tune the intake manifold for their competition car. This traditional method can only predict the engine speed and tuned peaks. In 2004, one dimensional simulation package was used to analyse the dynamics of pressure waves, the flow characteristics and energies in the intake and exhaust manifolds. With three dimensional CFD simulations, unsteady flows were visualised, allowed the explorations of the flow characteristics in the manifold in such a way that geometrical designs can be improved. Due to the absence of a plane or axis of symmetry in the entire manifold design, partial or 2D simulations were not possible. The non-symmetrical inlet manifold design is not common due to more complicated flows and unpredictable effects compared to the symmetrical manifolds.

Many lightweight vehicles use non-ventilated (also called vane-less or solid) iron alloy rotors in their vehicle braking systems both on the front and rear wheels. This solid rotor configuration is also common on the rear wheels of many full size production vehicles. This paper's object is to identify the heat transfer coefficients of such a solid brake disc arrangement using different experimental methods and then show how this information can be used both as a design tool and a simulator to predict temperatures in unknown or untested conditions.

In the automotive industries, time and parts production costs are fundamental, mainly in prototyping production. The RTV (Room Temperature Vulcanized) process is an important alternative production to flexible silicone molds when you need to inject polyurethane parts. The objective is time reduction in tooling production and parts. RTV requires notable initial investments in equipments. Many times, this cost does not fit in the automotive third part company's budget. This work shows how is possible to obtain parts by RTV process with excellent quality, without high investments in equipments and without quality loss in produced parts. Lead times and tooling and parts costs are analyzed. Due to equipments low costs, this alternative is accessible not only to automotive industries but also to small and medium suppliers.

The development of a new design criterion was necessary to provide the application of the engine MWM TD229-4 in a new agricultural tractor. The engine is a four stroke, Diesel cycle with four in line cylinders and it was applied to the tractor CNH TL75/85/95. The structural exigencies imposed to the tractor in a bench test demanded the study of a design criterion based on cumulative fatigue damage which utilized the Palmgren-Miner linear cumulative damage rule. This criterion was utilized in substitution of the current fatigue criterion by modified Goodman. The experimental tests have known loads and cycles where the modified Goodman criterion does not present a good correlation because it is developed to stress base, which does not consider plastic strains. The results obtained through Palmgren-Miner rule, in fatigue cumulative damage calculations, allowed to determine the engine structural components which needed to be modified to avoid crack opening during the experimental tests.

The new engine demands performance increasing, fuel consumption, exhaust-gas and noise emissions turn to diesel in special automakers. The way to improve fuel economy and thus the emition of less CO2 in diesel engines is an environmental challenge key for reducing emissions of nitrogen oxides (NOx) and particular matters. Market demands have resulted in development of high-performance fuel-injection system with higher pressure injection that better atomize fuel and precisely control injection timing and quantity. The valvetrain designers are faced with new requirements to achieve the new limits. The latest Tier II U.S. emissions regulations are being phased in between 2004 and 2007, when 100% of new registrations will have to comply. The multibody system dynamics based on the classical mechanics treated by Newton, Euler, D'Alembert and Lagrange and high developed in the last 15 years by Kortüm, Schiehlen and Huston.

Among manual wheelchair users has upper-extremity pain and injuries when self-propelling. However, manual propelling provides aerobic exercise. Powered wheelchairs are efficient to up/down ramps and long distance traveling, but it is heavy, bulky and the cost is very expensive. The ideal wheelchair system should have the advantages of both manual and powered wheelchairs. Therefore, it was developed the powered module for motorizing manual wheelchairs as a solution. This device is an intermediate alternative between manual and powered wheelchairs; it converts a manual wheelchair in a powered wheelchair. The module is a powered unit, which is attached, in all types of manual wheelchairs, quickly and easily by the user. It can be used for pushing or pulling the wheelchair in many environments. The purpose of this paper is to determine the dynamic behavior of the powered module-wheelchair.

This paper provides a survey about the consequences of a 42V Power Supply System for new vehicle projects, specially, its impact on directed project for Emerging Markets. At a first moment, it will be described new systems and its demand for additional power availability for future projects, such as electrical steering and brake systems; electrical air conditioning compressor; and electrical water and oil pumps. Following this subject, it will be presented possible alternatives for 14/42V Power Supply Systems, and also its impact over Power and Signal Distribution System components, such as connector, terminals, cables, relays, electrical centers, etc. Finally, the previous presented scenarios will be analyzed under a point of view for the Emerging Market demand for such new proposed systems, looking for best alternative driven.

Eddy-Current Testing applied to metallic automotive components production is used to monitor and diagnose deviations during the manufacturing phases. The signals are contaminated by noises, making the analysis of signals very difficult and sometimes impossible. The interpretation of these signals relies on subjective judgment, increasing the risk of over conservative or wrong conclusions. In this work, due to the transient characteristic of the signal, the Wavelet Transform is used to de-noise the original signal. The defect characteristics as defined in the ASME Code, can be obtained with much more accuracy. Also, a Fuzzy Logic inference engine is used to help inspector decision. Experimental data with different defects geometries were used.

This paper presents good results obtained by an integrated work between experimental and numerical simulation areas of DaimlerChrysler do Brasil to identify an undesirable vibration phenomenon observed in the cabin of a medium truck prototype, characterized experimentally. The phenomenon was reproduced in the modal and dynamic analyses using FEA, consistent with the performed measurements in the vehicle. Modifications on the project of cabin suspension were developed and approved in vibration analyses, showing a reduction of the acceleration values to acceptable levels when evaluated in the prototype. Due to these modifications, an evaluation under durability criteria was necessary. The stress analyses showed necessity of alteration in some components of the cabin suspension. The prototypes, with the new cabin suspension, were submitted to test bench and evaluation in high severity road (off-road) and urban traffic aiming at the final product approval.

In the competitive automotive market, industries are looking to reduce the product cost and its launch time. This work presents a vehicle accelerator pedal development using CAE tools to evaluate the design proposal and also a unique physical test performed in the final design. The objective of CAE analysis is to simulate the fatigue loading of the accelerator pedal bracket and dash area due to the accelerator pedal duty cycle. The simulation goal is to predict the likelihood of a fatigue failure and its severity in the accelerator dash mount with an estimative of the fatigue life. After the CAE design evaluation, it was performed a rig test and vehicle durability test, in order to approve the accelerator pedal new design. This job allowed saving engineer and physical test cost in a short development cycle.

Delphi's Zero Resistance Technology (ZRT) is a revolutionary new product/process that enables the reduction of mass and volume from a traditional wiring assembly. ZRT is defined as a minimal (zero) resistance change over time. The ZRT product is an electrical/electronic connection system which provides a viable solution for high density and limited space wiring applications. The ZRT process is a semi-automated wiring harness manufacturing system with flexibility to produce harnesses to the customer demand.

Vehicle radiators water tanks must withstand high pressure and temperature loads when in use. In most applications, they are made out of plastic material, usually Polyamide 66, filled with glass fiber to increase the stiffness, and molded by injection. However, in many cases, their geometry complexity can not prevent different plastic material flow fronts from meeting in different regions during the mold cavity filling process, hence creating weld lines. Since regions presenting weld lines tend to have weaker mechanical resistance, their precise location become of primary interest and require more attention, so that their response to the mechanical stress resulting from the radiator normal load conditions can be studied. In such cases, in order to optimize the product development process, to avoid early failures about the weld lines regions and to reduce the final validation time, computational simulation tools are used during the product concept and design phase.

Disc brake noise and vibration control in vehicle interiors has received significant attention in the last years. Creep Groan is a kind of brake system low frequency noise that usually appears in low velocity situation, where there is a transition from static to dynamic condition under brake disc low pressure. The usual method for measuring the creep groan is based on a subjective test pilot evaluation realized on different ramp inclinations. This method, which is realized in the final vehicle, is not very precise and can generate different results associated to breaking noise for different pilots. This work proposes a method for creep groan measuring, which can reduce subjective interpretation throughout the generation of graphics and tables results. To compare the results, final vehicle and laboratory, i.e. inertial brake dynamometer tests were realized.

Masking effect can be considered as the sound decrease in audibility when another sound called masker is present. Vehicle Wind Noise attribute is facing with several components contributors which present masking effect. The purpose of this paper is illustrate this phenomenon.

This paper describes highlights and overall improvements achieved on the development of the Ford Zetec RoCam 1.6l Flex Fuel engine for the Brazilian market. The Brazilian market offers oxygenated fuels; (i) hydrated ethanol, known as alcohol or simply E93 (93% of ethanol) and (ii) Brazilian gasoline also known as gasohol or simply E25 (Brazilian gasoline is a mixture of pure gasoline with 24% to 26% of anhydrous ethanol), fuels characteristics are detailed on the appendix. In 2003 automakers started to offer vehicles capable to run with both fuels and any mixture in between instead of offering only vehicles capable to run only with one fuel. These vehicles called flexible fuel vehicles (FFV) or simply flex fuel vehicles are yearly increasing their market share due to the customer benefit of choosing the fuel as a function of price, availability and performance versus driving range.

The Diesel engine popularity has been increasing for the last years, mainly in Europe, where the Diesel passenger cars fleet surpassed the petrol one. Such popularity is not only a result of fuel consumptions benefits, but also a result of a combination of all engine attributes performance including powertrain NVH and drivability. Thus, the common rail technology must provide capabilities to improve the attributes for this competitive and demanding market. This paper intends to idealize the drive-by-wire response in Diesel engines, which is a technological feature that contributes to achieve the customer vehicle performance feel and drivability expectation.

In this study the moan and whine noises of the pumps of the Hydraulic Power Steering systems are investigated experimentally through the measurements of the dynamic hydraulic pressure in the pump outlet installed in a test stand. The vibro-acoustic performance of the pumps is evaluated applying two objective metrics. One of them consisted of the pressure amplitude sum and the other identified the maximum amplitude, in the frequencies of interest (fundamental frequency and harmonics). The results of the dynamic pressure measurements of pumps installed in a test stand are compared with the subjective qualification of the same pumps installed in an actual vehicle by the grades given by trained listeners.

The brake drums are designed to convert kinetic energy of the vehicle into thermal energy. The stress originated by thermal transients produced by braking process may nucleate fatigue cracks and lead the component to failure. The aim of this work is to study thermal fatigue life for brake drum made with gray cast iron and vermicular cast iron. The loading transients due to different braking events were determined by thermal analysis, using FEM methods. Stress amplitudes and mean stresses were obtained. The fatigue life of the component has been evaluated and the points with the highest probability for crack nucleation were determined. The highest level of stress was observed in the hoop direction when the brake drum is made in gray cast iron and in the radial direction when it is made with vermicular graphite cast iron.

The main functions of the air intake system are: supply air to the engine, filter particles, tuning the dynamic performance and filter acoustic noise. The last function can be characterized using parameters which will describe the performance of a general acoustic system. This includes: Noise Reduction, Insertion Loss and Transmission Loss. Among them, the transmission loss is a property of the acoustic system that represents the difference in the sound power level between the incident and transmitted waves. To measure the transmission loss in a simple and practical way, a rig test is proposed using an improved anechoic termination whose results presents a good agreement compared with analytical data. To validate the methodology, a simple expansion chamber with common dimensions is used as an acoustic element.