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This study is a joint development project between Chrysler Corporation and CFD Research Corporation. The objective of this investigation was to develop a 3D computational flow and heat transfer model for a vehicle windshield de-icing process. The windshield clearing process is a 3D transient, multi-medium, multi-phase heat exchange phenomenon in connection with the air flow distribution in the passenger compartment. The transient windshield de-icing analysis employed conjugate heat transfer methodology and enthalpy method to simulate the velocity distribution near the windshield inside surface, and the time progression of ice-melting pattern on the windshield outside surface. The comparison between the computed results and measured data showed very reasonable agreement, which demonstrated that the developed analysis tool is capable of simulating the vehicle cold room de-icing tests.

The flow field contained within ten planes inside a cylinder of a 3.5 liter, 24-valve, V-6 engine was mapped using a three-dimensional Laser Doppler Velocimetry (3-D LDV) system. A total of 1,548 LDV measurement locations were used to construct the time history of the in-cylinder flow fields during the intake and compression strokes. The measurements began during the intake stroke at a crank angle of 60° ATDC and continued until approximately 280° ATDC. The ensemble averaged LDV measurements allowed for a quantitative analysis of the dynamic in-cylinder flow process in terms of tumble and swirl motions. Both of these quantities were calculated at every 1.8 crank degrees during the described measurement interval. Tumble calculations were performed about axes in multiple planes in both the Cartesian directions perpendicular to the plane of the piston top. Swirl calculations were also accomplished in multiple planes that lie parallel to the plane of the piston top.

This paper discusses simplified lumped parameter thermal modeling of power train components. In particular, it discusses the tradeoff between model complexity and the ability to correlate the predicted temperatures and flow rates with measured data. The benefits and problems associated with using a three lumped mass model are explained and the value of this simpler model is promoted. The process for correlation and optimization using modern software tools is explained. Examples of models for engines and transmissions are illustrated along with their predictive abilities over typical driving cycles.

A few years ago, electric vehicles (EVs) were considered to be objects of the distant future … technology that was still in its infancy, not yet ready and for those outside the “high pollution” areas probably not even worth the expenditure. But the present day scenario has changed dramatically. In the United States of America, several states are following California's lead and the need for the operating fleets to commit to purchase of Zero Emission vehicles (ZEVs) is becoming a requirement. In order to make the technology available to the utilities … as well as the public, state of the art, affordable batteries are essential for making EVs a reality and an effective means of transportation.

The Chrysler wind tunnel is a closed-circuit, single-return, semiopen jet facility used for performing engine cooling, transmission cooling, engine compartment airflow, underhood component temperature, air-conditioning, and other types of tests. It operates over a 0-120 mph speed range with 400 hp rear-wheel power absorption capacity. Special provisions have been made for idle, city traffic, and tail wind tests. Facility controls provide precise set-point capability, and comprehensive instrumentation and data acquisition systems permit measurement of many parameters and real time data reduction.

The SAE Recommended Practice J963 “Anthropomorphic Test Device for Dynamic Testing” describes a standard 50th percentile adult male anthropomorphic test dummy. For nearly three years the Crash Test Dummy Task Force worked with the limited data available in selecting values for the body dimensions and ranges of motion. The data for specifying the values of mass distribution were developed experimentally as was a test procedure for determining the dynamic spring rate of the thorax.

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.

The development of the AUTO TEMP II Temperature Control System used in Chrysler Corp. vehicles is summarized. A description of the design, development, function, and manufacturing aspects of the control system is presented, with emphasis on unique control parameters, reliability, serviceability, and check-out of production assemblies. Auto Temp II was developed by Chrysler in conjunction with Ranco Incorporated. The servo-controlled, closed-loop system, which has a sensitivity of 0.5 F, utilizes a water-flow control valve for temperature control, along with a cold engine lockout. The basic components are: sensor string, servo, and amplifier. All automatic functions involving control of mass flow rate, temperature, and distribution of the air entering the vehicle, are encompassed in one control unit. All components are mechanically linked through the gear train and are responsive to the amplifier through the feedback potentiometer.

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.

THIS paper outlines tests made to verify the SAE recommended practice for estimating truck ability performance described in TR-82. The author has collected data on four vehicles and compares it with the results computed in TR-82 and with a Method X. The data includes information on air and rolling resistance, effect of wind velocity, chassis friction power, grade ability, and the like. The author concludes that the SAE method of TR-82 is at the present time the most reliable method for computing truck ability.

TFC/IW, total fuel consumption divided by inertia (test) weight is a useful concept in analyzing the total or composite fuel economy generated in thousands of tests using the carbon balance technique in EPA Federal Test Procedure and Highway Driving Cycle. TFC/IW is a measure of drive train efficiency that requires no additional complicating assumptions. It is applicable to one test or a fleet representing many tests.

An automotive cockpit module is a complex assembly, which consists of components and sub-systems. The critical systems in the cockpit module are the instrument panel (IP), the floor console, and door trim assemblies, which consist of many plastic trims. Stiffness is one of the most important parameters for the plastic trims' design, and it should be optimum to meet all the three functional requirements of safety, vibration and durability. This paper presents how the CAE application and various other techniques are used efficiently to predict the stiffness, and the strength of automotive cockpit systems, which will reduce the product development cycle time and cost. The implicit solver is used for the most of the stiffness analysis, and the explicit techniques are used in highly non-linear situations. This paper also shows the correlations of the CAE results and the physical test results, which will give more confidence in product design and reduce the cost of prototype testing.

A running loss test procedure has been developed which integrates a point-source collection method to measure fuel evaporative running loss from vehicles during their operation on the chassis dynamometer. The point-source method is part of a complete running loss test procedure which employs the combination of site-specific collection devices on the vehicle, and a sampling pump with sampling lines. Fugitive fuel vapor is drawn into these collectors which have been matched to characteristics of the vehicle and the test cell. The composite vapor sample is routed to a collection bag through an adaptation of the ordinary constant volume dilution system typically used for vehicle exhaust gas sampling. Analysis of the contents of such bags provides an accurate measure of the mass and species of running loss collected during each of three LA-4* driving cycles. Other running loss sampling methods were considered by the Auto-Oil Air Quality Improvement Research Program (AQIRP or Program).

For designing new products or developing new specifications, the reliability performance of systems and components experienced by the customer provides invaluable information for the engineer. This information, not only provides for the visibility of reliability requirements, but also an awareness of potential degradation of the systems and components during its life cycle. In this paper, a method is presented for predicting vehicle system and component reliability from vehicle fleet repair data. This method combines sampling stratification, computer data analysis and statistical modeling techniques into a reliability analysis procedure to provide reliability prediction. Specifically, published vehicle fleet data was used to provide the basis for predicting the vehicle system and component reliability at any mileage level.

The reliability of an electronic sensor in the automotive applications is assessed using data from Fleet Test and proving ground Vehicle Endurance test. These nonfailure data are multiply censored at different mileage. Reliability analysis of data with no failure is rarely discussed in most reliability literature. This paper applies the Weibull maximum likelihood analysis based on known values of the Weibull shape parameter to extract useful reliability information. The well-known Weibayes and Weibest methods are subsets of the discussed approach. The sensitivity of the change of reliability levels over a range of Weibull shape parameter values is also examined in our case. The Huang-Porter (1991) approach of obtaining a reliability lower bound regardless of the Weibull shape parameter values is also applied and its potential of practical application is discussed. Practical limitations of all methods are discussed.

The low noise and linear sound level characteristics of passenger vehicles are receiving increased scrutiny from automotive journalists. A linear noise level rise with increasing engine rpm is the first basic aspect of insuring an acceptable vehicle interior engine noise sound quality. In a typical case of structural response to engine vibration input, interior noise begins to rise with rpm, remains constant or even drops as the engine continues to accelerate, and then exhibits a noise period corresponding to the structure's natural frequency. Frequently this nonlinearity is bothersome to the customer. During the development process, Chrysler's Dodge and Plymouth Neon exhibited just such a nonlinear rise in noise level, heard within the passenger compartment, when the vehicle was accelerated through 4200 rpm.

Vacuum insulation and phase-change thermal storage have been used to enhance the heat retention of a prototype catalytic converter. Storing heat in the converter between trips allows exhaust gases to be converted more quickly, significantly reducing cold-start emissions. Using a small metal hydride, the thermal conductance of the vacuum insulation can be varied continuously between 0.49 and 27 W/m2K (R-12 to R-0.2 insulation) to prevent overheating of the catalyst. A prototype was installed in a Dodge Neon with a 2.0-liter engine. Following a standard preconditioning and a 23-hour cold soak, an FTP (Federal Test Procedure) emissions test was performed. Although exhaust temperatures during the preconditioning were not hot enough to melt the phase-change material, the vacuum insulation performed well, resulting in a converter temperature of 146°C after the 23-hour cold soak at 27°C.

THE GRADEABILITY formula can be used as the basic means for rating a truck transmission. By correlating the gradeabilities in the various gear ratios with a highway requirement probability curve, the per cent of time in each ratio can be obtained. The required hours of gear life for each ratio are then determined, and compared with the available gear life in the ratios. This procedure gives a detailed analysis of a transmission rating for one vehicle specification at a specified mileage between overhauls. A limitation of the system is that it cannot be applied quickly to various vehicle specifications. The paper outlines the method for constructing a nomogram to overcome this.*

A SIMPLE method of predicting truck performance in terms of grade ability at a given road speed, taking into consideration rolling resistance, air resistance, and chassis friction is presented here. A brief review of fundamental considerations is given first, then the method recommended for predicting vehicle ability at a selected speed, and finally a few words on the prediction of maximum possible road speed and selection of gear ratios. The basis of the solution is the determination and expression of vehicle resistances in terms of horsepower - that is, in terms of forces acting at a velocity. A convenient method of solving the grade problem at a given speed is by means of a tabular computation sheet, which is given, together with tables and charts. These assist in making the computation an easy one as well as giving the necessary data on vehicle resistances.