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Dynamic tests have been performed on carbon fiber racing seats following the FIA regulations. The tests have shown, in rear impact tests, a relatively strong rebound leading to large forward bending of neck, and, in side impact tests, very large lateral displacement of the head, the latter protruding dangerously towards hard portions of the car structure. Stiffening the seat back by steel struts results in reducing strongly both the motion and the acceleration of the head. Simulations of the dynamics of the tests have been done with multi-body models, including the Hybrid III dummy and seat deflection, by means of the program VEDYAC. It has been found that computer simulation can predict very accurately the result of a test, provided the numerical models have been carefully calibrated to match the dummy tolerance bands. Once they have been calibrated and validated with a number of tests, the computer models can be very useful to extend the test results to different test conditions.

The use of aluminium cast components as the uprights is as old as racing; nevertheless this traditional technology is still a standard on budget racing cars, where the advantages of a steel sheet, welded upright are simply not affordable. It is very well known that cast uprights allow for savings in the case of large production numbers (where “large” should be intended relatively to the racing world). The upright is the component which links the wheel and brake to the rest of the suspension. Being subjected to all the road loads and part of the unsprung mass, it is a fairly critical component. Any failure can lead to an accident; also, it must be as stiff and light as possible for better suspension performance hence roadholding. The paper describes the design of a small single-seater cast upright from the drafting phase to FEM computation to experimental testing. It is a case study rather than an innovative project, but it could be a reference for those involved in a similar design.

Extensive crash sled testing and analysis has recently led to the development of a new HANS prototypes for use in FIA F1. The performance of HANS prototypes has been studied with various conditions of HANS design geometry and impact direction. The new HANS prototypes have been found to substantially reduce injurious motions and forces of the head and neck, and the new HANS is lighter, more compact, and performs better than the currently available HANS. Use of HANS by FIA F1 drivers has been initiated.

An efficient light weight 425 Watts charging system was developed and built to meet the requirements of a 12-cylinder engine for racing application. The new system consists of a permanent magnet (PM) alternator with MAGNEQUENCH (MQ3) magnets and a high frequency switching regulator to regulate the output voltage over the engine speed range of 2,000-12,000 rpm. The system has been tested for 75% overall efficiency as compared to 38% for the present system over most of the speed range. Excellent dynamic response (less than 1 ms) has been measured, which allows the alternator to support pulsed loads, even if the battery is disconnected during operation. The new system weighs 3.73 kg vs 5.4 kg of the existing system.

This paper describes the development of a new generation of permanent magnet alternators (PMA), intended for use in Formula One motorsport. The challenging problem of how to regulate the output from a PMA has been solved by the creation of a voltage regulator that draws power from the alternator as and when necessary, rather than dumping excess energy as heat. As a result, a compact, lightweight system has been created, which is capable of delivering 30A to the load at 14V. The system can achieve a cut-in speed of less than 1800rpm and can deliver 25A at 4500rpm.

This paper summarizes an investigative study done to evaluate the feasibility of a Ford Duratec engine in 2.0 L Touring Car Racing. The investigative study began in early 1996 due to an interest by British Touring Car Championship and North American Touring Car Championship sanctioning bodies to modify rules & demand the engine be production based in the vehicle entered for competition. The current Ford Touring Car entry uses a Mazda based V-6. This Study was intended to determine initial feasibility of using a 2.0 L Duratec V-6 based on the production 2.5L Mondeo engine. Other benefits expected from this study included; learning more about the Duratec engine at high speeds, technology exchange between a production and racing application, and gaining high performance engineering experience for production engineering personnel. In order to begin the Duratec feasibility study, an initial analytical study was done using Ford CAE tools.

The paper compares 3.0 liter F1 engines having different architectures and developed in compliance with the 1998 FIA Technical Regulations. Similarity rules and non dimensional parameters from previous projects define key geometric and operating parameters for V10 and V12 engines having equal degree of sophistication. The paper presents computed classical engine outputs versus engine speed, including brake, indicated and friction values. The V12 solution shows clear advantages in terms of pure engine performances.

This paper reviews the development of a new test capability for race cars at the Langley Full-Scale Tunnel. The existing external force balance of the Langley Full-Scale Tunnel, designed for use with full-scale aircraft, was reconfigured for automobile testing. Details of structural modifications relevant to supporting cars and force measurements are shown. A specialized automobile force balance, measuring vehicle drag and individual wheel downforce, was then designed, constructed and calibrated. The design was governed by simplicity and low cost and was tailored to the stock car racing community. The balance became fully operational in early 1998. The overall layout of the automobile balance and comparisons to reference data from another full-scale wind tunnel is presented.

Airflow characteristics of simulated heat exchangers for wind tunnel models are determined for various situations. These situations include inclining the core at various angles to the flow direction, simulating the exit ducting and turning vanes as used by many open wheeled racing series, such as CART's Champ Car series or FIA's Formula One. The characteristics determined include the blockage and the estimated heat rejection of the radiators. The Results of this investigation show that perforated plates are adequate for heat exchanger simulations in wind tunnel models.

The acoustic phenomena which take place inside an intake system greatly influence the volumetric efficiency of an engine. This paper deals with the problem of improving the volumetric efficiency of a single cylinder engine for a wide range of frequencies. The proposed solution is the addition of tunable resonators to the intake system. The variation of resonator tuning makes it possible to exploit the acoustic vibrations for a wide range of piston frequencies in the best way. Several intake systems equipped with resonators are studied using analytical methods. The best results are obtained when an in-series resonator with a variable volume is placed near the cylinder and when a side-branch resonator with a variable cross section is connected to a constant volume resonator. Several results are presented which deal with the behavior of the intake system during the induction stroke and which show the effectiveness of tunable resonators.

An experimental study was performed at the University of Illinois at Urbana-Champaign Low-Speed Wind Tunnel to quantify the performance and flowfield effects of two-element open-wheel-race-car front wing configurations. Four distinct configurations were tested in- and out-of-ground effect and at various speeds (Reynolds numbers), angles of attack, and flap positions. A splitter plate was installed in the wind tunnel to act as the ground plane. Data presented include balance force measurements, surface pressure data, and downstream flow measurements using a seven-hole probe. Results show that these elementary factors in the design of race-car front wings have a significant effect on wing performance and behavior of the downstream flowfield.

A lightweight sports car prototype named “PT 97 A Promise” was built by the Scuderia Bizzarrini Co. at the beginning of 1997 in Livorno, Italy. The “PT 97 A” was developed for the purpose of achieving very high performance on normal roads through lightweight construction. This paper describes the main features of the car and a computer model for predicting vehicle performance during track tests. A performance simulation of the “PT 97 A” on the race track of Fiorano is also presented, along with other data.

This paper presents a unique empirical approach for the design dimensioning of the valving and the ducting of a high performance, naturally aspirated, spark-ignition automotive engine so as to attain the required performance levels at a given engine speed. The contentions behind these several empirical criteria are checked out, firstly by analysing the geometry of a number of famous racing engines and, secondly, systematically testing each element of the empirical criteria using an engine simulation model of an actual and well-optimised, four-cylinder high performance engine. The use of detailed empirical theory for this purpose permits the designer to more rapidly optimise racing engines by entering data into an engine simulation model in a logical manner with data which is already well-matched empirically before so doing.

One of the hidden aspects of the past Formula One season was the use of indoor road simulators as a mean of speeding up the springing and damping set-up over the race weekend. According to the rumours some teams can perform an indoor set-up optimization overnight by reproducing freshly acquired road profile data. The optimized set-up is then communicated back to the team and tested on-track the day after. The optimization is carried out on a so-called hydraulic four-post rig (or seven-post rig), where a car is shaken at such frequencies and amplitudes to reproduce the same inputs and forces encountered during a typical circuit lap. The Vehicle Dynamics Group of the University of Brescia has recently acquired a four-post rig by Servotest England. The paper aims to describe this facility while future papers will describe the first results obtained in research.

Over the past 5 years, over six major new racing venues and nearly one dozen existing courses have been constructed or re-paved with asphalt, respectively. Major racing surface failures and successes have evidenced themselves throughout the entire process, thus enabling the industry to take modest strides to greater understand the ingredients necessary in creating exciting, safe, and durable racing surfaces. Failure modes stemming from track geometry to ambient temperatures have played a role and have required re-evaluation of the paving process. A close look at surface specification development, detailed quality control and quality assurance and ongoing maintenance will bolster track surface performance

This paper reviews the literature which identifies the causes, consequences and cures for engine knock as it affects high performance engines. The physical events of normal and abnormal combustion are described. The observed variations in combustion phenomenon are explained through chemical kinetics. A mathematical model of combustion which can predict knock in an engine cylinder is summarized. Several mechanisms of knock induced damage are outlined. Design and operating considerations which affect an engine's propensity to knock are discussed. Terms that have become associated with combustion in general and the knocking phenomenon in particular are collected and examined

During the starting of the vehicle, the friction clutch engagement sometimes generates judder. Judder prevents vehicles from starting smoothly, harms the ride comfort, and may produce damage to the drivetrain components. This unpleasant phenomenon, which often manifests in the form of noisy torsional vibrations of the drivetrain or a violent surging of starting vehicles, is an example of the many annoying problems that automotive engineers have been experiencing since the car was invented. Engineers and scientists have identified some causes of transient torsional oscillations connected to judder. Vibrations generated by the clutch facings when a special type of relationship between the friction coefficient and sliding speed occurs account for the most important source of judder.

For cast iron automotive parts, the automated shape optimization technique is a powerful design tool that usually enhances performance and reduces overall cost. Possessing the solid finite element model of what could be considered a starting point, first trial or initial design, commercially available structural synthesis software are able to optimally relocate the nodes, thus creating an optimal final shape. This is very suitable for parts obtained by metal melting for two main reasons: first, such components generally tend to be massive (posing the challenge to reduce weight) and second, the manufacturing method itself presents wide freedom regarding the shapes possible to be obtained (augmenting the chances the computationally generated shape is feasible in practice).

The ability of performance-based brake testers (PBBTsa) to accurately determine the braking capability of commercial vehicles was investigated through a field study of over 2,800 trucks and buses. Under certain conditions, good agreement was found between the observation of brake-related defects by visual inspection and the measurement of weak brake forces by a PBBT. It was determined that the PBBTs' assessment was an independent measure of a vehicle's as-is braking capability, and should not be expected to correlate well with a visual inspection under any condition. It was also determined that predictions of stopping capability should be possible combining the PBBT results of the brake force and axle load measurements with certain assumptions regarding brake application time and road/tire coefficient of friction.