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Piston design is a challenging engineering problem which involves complex physics and requires satisfying multiple performance objectives. Uncertainty in piston operating conditions and variability in piston design variables are inevitable and must be accounted for. The piston assembly can be a major source of engine mechanical friction and cold start noise, if not designed properly. In this paper, an analytical piston model is used in a deterministic and probabilistic (reliability-based) multi-objective design optimization process to obtain an optimal piston design. The model predicts piston performance in terms of scuffing, friction and noise, In order to keep the computational cost low, efficient and accurate metamodels of the piston performance metrics are used. The Pareto set of all optimal solutions is calculated allowing the designer to choose the “best” solution according to trade-offs among the multiple objectives.

In order to achieve optimum performance from an engine a homogeneous air fuel mixture must enter the combustion chamber. There are a number of factors that affect the mixture; this study focuses on the flow through a cylinder head port. This paper investigates the shape of a cylinder head port effects on the flow of the port and the horsepower and the torque of the engine. Two port shapes were examined, the stock port shape which is round and a modified port shape which is approximately an upside down triangle. By using computational and experimental analysis a direct relationship is demonstrated between the shape of the port and the performance characteristics of the engine.

Brake-based traction control systems (TC), which utilize the brake of a spinning wheel of the drive axle, are widely used in passenger cars and light trucks, and recently were applied to all-wheel drive construction equipment. Such machines employ various types of interwheel drive systems (i.e., axle drives such as open differentials, limited slip differentials, etc.) to control torque split between the drive wheels and, thus, improve vehicle traction performance. As experimental research showed, the interaction between the traction control system and the axle drive can lead to unpredictable changes in vehicle performance. Lack of analytical work in this area motivated this study of the interaction and impact of the two systems on each other and the dynamics and performance of a drive axle.

This paper discusses the feasibility and issues associated with integrating a consumer off-the shelf product into a vehicle. For this evaluation, we selected a handheld personal computer (HPC), cellular telephone and modem to integrate with the vehicle audio, climate and system controls. Connectivity between the HPC and the vehicle is established by the use of the standard infrared serial data link that comes with the HPC. Connectivity outside the vehicle uses a cellular telephone for voice and a cellular digital packet data (CDPD) modem for data. This system is built into the Dodge ESX-2 hybrid powered concept vehicle for demonstration.

The rapid growth of information technology has the potential to affect many of the reasons why people drive. The Internet is arguably the most significant recent milestone in the growth of information technology. This paper examines the ways Internet communication might affect the travel experience by a) eliminating traditional reasons for personal travel, b) providing new reasons, c) changing the balance between personal and freight travel, and d) changing trip length distribution. Changes of the types listed could affect the product demand "mix" for electric, hybrid-electric and fuel cell vehicles being developed.

Adhesive bonding has many applications in the automotive industry. The single-lapped bonded joint is the most typically used among various bonding types. This paper presents experimental research for determining the strain field of the single-lapped joint under tensile loading. The materials for the joint are epoxy-based structural adhesive and low-carbon electrolytic zinc steel plate. In the study, a DIC (digital image correlation) system was adopted to measure the strain distribution of the bonded joint during a tensile test. The bonded steel coupons in the tensile test were prepared according to the ASTM standard. During the measurement, images of the coupon joint were taken before and after the deformation process. Then the DIC system measured the strain of bonded joint by comparing two consecutive images. The measured data from the DIC was compared to data taken simultaneously from a traditional extensometer.

The automobile industry has an increasing demand for lightweight components, improve product performance, efficiency and increase safety. For optimization of design and manufacturing of these components the detail measurement of critical material properties such as strain limit, strength coefficients, anisotropy coefficients et al, are required. The most commonly used method for finding the material properties is tensile test with extensometer. But this system only provides an average strain over the specimen gauge length and is not applicable to post diffuse necking. Digital Image Correlation (DIC) technique is the latest state of art technique. Because of its capability of fast data acquisition, this technique is suited well for characterization of material properties both in the elastic and plastic ranges. It also has advantages of full field, non-contact, and considerately high precision for displacement and strain measurements.

The Magnetostrictive Dynamic Strain Sensor is a permanent-magnet constant-flux excitation sensor and thus requires no other electrical excitation or power source. It does not require any signal conditioning. Since it is a constant-flux dynamic sensor, it does not generate any offset voltage and it does not exhibit temperature or drift problems. Furthermore, the sensor is rugged, simple and inexpensive. The sensor's time-averaged output is constantly zero. The sensor detects only dynamic events such as impact, crash, firing (or misfiring) of an engine cylinder, piston slap, vibrations of a machine component, vehicles passing through a bridge, etc. Therefore, the sensor has many promising automotive applications including crash and misfire detection.

The primary function of the electrical system for the Lawrence Tech Formula SAE 2001 vehicle was to supply essential engine and vehicle functions. Important secondary functions of the electrical system were real-time data acquisition, display of some of these data to the driver, and transmission of the data to race team members at a sideline location. In addition to data channels depicting vehicle function and health, the data-acquisition (DAC) system included video that duplicated the driver's view, and two-way audio. This paper describes the DAC system and its integration into the vehicle electrical system.

Tapered roller bearings have proven successful in a number of high-volume automatic transaxle designs. Typically, tapered roller bearings are required to carry high loads generated by helical and hypoid gears. To meet the demands of a successful design, a number of factors must be considered in the selection and application of tapered roller bearings. This paper presents a discussion of these factors as well as results from Chrysler's transaxle testing. Selection of tapered roller bearings is based on the transmission duty cycle developed using load and speed histograms, gear data, size constraints, and life requirements. A bearing life analysis considering the total transaxle system is conducted using a sophisticated computer program. Various system effects are analyzed including the load/speed cycle, housing and shaft rigidity, lubrication, bearing setting, thermal effects, and bearing internal design.

Higher horsepower per liter engines have put more demand on the crankshaft, often requiring the use of forged steel. This paper examines cost reduction opportunities to offset the penalties associated with forged steel, with raw material and machinability being the primary factors evaluated. A cost model for crankshaft processing is utilized in this paper as a design tool to select the lowest cost material grade. This model is supported by fatigue and machinability data for various steel grades. Materials considered are medium carbon, low alloy, and microalloy steels; the effects of sulfur as a machining enhancer is also studied.

A new, 1-D analytical engine thermal management tool was developed to model piston, oil and coolant temperatures in the Ford 3.5L engine family. The model includes: a detailed lubrication system, including piston oil-squirters, which accurately represents oil flow rates, pressure drops and component heat transfer rates under non-isothermal conditions; a detailed coolant system, which accurately represents coolant flow rates, pressure drops and component heat transfer rates; a turbocharger model, which includes thermal interactions with coolant, oil, intake air and exhaust gases (modeled as air), and heat transfer to the surroundings; and lumped thermal models for engine components such as block, heads, pistons, turbochargers, oil cooler and cooling tower. The model was preliminarily calibrated for the 3.5L EcoBoost™ engine, across the speed range from 1500 to 5500 rpm, using wide-open-throttle data taken from an early heat rejection study.

As a regulated public utility, Consumers Energy constantly struggles to lower operating costs, so that customers can enjoy competitive rates for the natural gas they consume across the state of Michigan. Elimination of line heaters altogether would be one very desirable method of reducing operating cost, unfortunately, Joule Thomson cooling, and the trouble it causes is a fact of life for the natural gas transmission and distribution utilities. Considering this, the operation of line heaters must be optimized so that operating cost can be minimized. Line heaters must be sized appropriately, and controlled so that they are large enough to heat efficiently, but not oversized. Once a heater is installed, the temperature band that it operates within must be set appropriately. This work presents theory that, over time will improve the efficiency of the operation of line heaters within Consumers Energy. Two objectives of this work will be presented.

The dynamics of an AWD vehicle is determined by the interactions between the vehicle's wheels and the tire contact surface. Understanding and controlling these interactions drives the vehicle mobility and energy efficiency. In this paper new issues related to tire slippage control are addressed. The paper analytically demonstrates that two tires on the same axle with the same rotational speeds can have different slippages when the normal reaction and inflation pressure vary due to motion conditions. Hence, a new method is proposed to control the rotational velocity of the wheels in a way that provides the same slippages of the tires by accounting for changes in the normal load and tire inflation pressure. This approach is especially beneficial for vehicles with individual (electric) wheel drives which can be individually controlled by introducing the proposed algorithm for controlling both the vehicle linear velocity and the tire slippages.

The power and torque output of an engine (for a Formula SAE vehicle) can be dramatically improved through good intake design. For example, performance can be improved by reducing pressure losses in the intake system, or by improving the restrictor's design to increase airflow at lower pressure drops. A plenum design with equal air distribution to all cylinders can also be helpful. In this study, four different intake designs were tested on a dynamometer and the power outcomes were compared. Based on theory and lab testing and intake system was designed to optimize throttle response as well as low-end torque; a steady flow of air passes through the throttle body and the restrictor and then into the plenum. Dynamometer testing confirmed an overall increase in torque and horsepower compared to earlier designs.

This study analyzes the vibration characteristics of the valve train of a 2.0L SOHC Chrysler Corp. Neon engine over a range of operating speeds to investigate and demonstrate the advantages and limitations of various dynamic measurements such as displacement, velocity, and acceleration in this application. The valve train was tested in a motoring fixture at speeds of 500 to 3500 camshaft rpm. The advantages of analyzing both time and frequency domain measurements are described. Both frequency and order analysis were done on the data. The theoretical order spectra of cam displacement and acceleration were computed and compared to the experimental data. Deconvolution was used to uncover characteristic frequencies of vibration in the system. The theoretical cam acceleration spectrum was deconvolved from measured acceleration spectra to reveal the frequency response function of the follower system.

A Methanol Concentration Smart Sensor has been developed to support the demand for alternately fueled vehicles operating on blends of methanol and gasoline in any mixture up to 85% methanol. The sensor measures concentration by exploiting the difference in dielectric properties between methanol and gasoline. The measurement is made based on the distributed capacitance of a coil of wire, contained in a reservoir through which the fuel passes. This signal, along with temperature compensation inputs, is then fed to an integral microprocessor, which provides a voltage output proportional to the methanol concentration of the fuel. The Powertrain Controller uses this information to modify injector pulse width and provide proper spark advance. This paper will explain the sensor's development methodology and function.

Typical sand-casting techniques have been shown to be inappropriate in pouring particulate reinforced aluminum metal matrix composite (Al-MMC) castings. New gating/risering configurations were necessary to produce castings of acceptable soundness. Several automotive components, including brake rotors, cylinder liners and camshaft thrust plates, were prepared using special techniques. Initial durability test results of several Al-MMC prototype components are presented.

A new electronically controlled transaxle has been put into production for Chrysler's family of LH cars. Among the attributes of this new transaxle are its ability to handle engines of high torque and high power coupled with high-speed shifts. Engine torque management is used in specific operating regimes. A feature of the transaxle is electronic modulation of the converter clutch. A number of logic features have been combined with hardware to provide good performance and shift quality over a wide operating range. An output transfer chain and a hypoid gear set are used to provide torque to the front wheels in a longitudinal power train orientation. Obtaining acceptable endurance life of the hypoid gears within an aluminum housing presented a significant challenge. New approaches were required to provide a chain-sprocket system with acceptable noise characteristics.

Chrysler Corporation has developed an 8.0-liter engine for light truck applications. Numerous features combine to produce the highest power and torque ratings of any gasoline-fueled light truck engine currently available while also providing commensurate durability. These features include: a deep-skirt ten-cylinder 90° “V” block, a Helmholtz resonator intake manifold that enhances both low and mid-range torque, light die cast all-aluminum pistons for low vibration, a unique firing order for smooth operation, a “Y” block configuration for strength and durability, a heavy duty truck-type thermostat to control warm up, and a direct ignition system.