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A primary goal within the industry is to shorten the lead time to get shorter time to market and lower cost. System verification can set the limits for how short the lead time can be. Traditionally verification of automotive communication systems like Remote Keyless Entry, RKE, is performed in a complete vehicle late in the product development process. To fulfill the quality demands during the shorter project time Volvo Cars, VCC, has experienced that it is necessary to develop new requirements and verification methods. Six Sigma contains a complete toolbox to do this in a structured and time efficient way. VCC has together with other Ford Motor Company, FMC, brands and the supplier Continental developed methods and requirements so that the RKE system can be verified before vehicles are built. Only a last validation has to be performed in a complete vehicle.

This study focus on the aerodynamic influence of the engine bay packaging, with special emphasis on the density of packaging and its effect on cooling and exterior flow. For the study, numerical and experimental methods where combined to exploit the advantages of each method. The geometry used for the study was a model of Volvo S60 sedan type passenger car, carrying a detailed representation of the cooling package, engine bay and underbody area. In the study it was found that there is an influence on the exterior aerodynamics of the vehicle with respect to the packaging of the engine bay. Furthermore, it is shown that by evacuating a large amount of the cooling air through the wheel houses a reduction in drag can be achieved.

This paper presents a new method to derive the tire forces for simultaneous braking and cornering, by combining empirical models for pure braking and cornering using brush-model tire mechanics. The method is aimed at simulation of vehicle handling, and is of intermediate complexity such that it may be implemented and calibrated by the end user. The brush model states that the contact patch between the tire and the road is divided into an adhesion region where the rubber is gripping the road and a sliding region where the rubber slides on the road surface. The total force generated by the tire is then composed of components from these two regions. In the proposed method the adhesion and the sliding forces are extracted from an empirical pure-slip tire model and then scaled to account for the combined-slip condition. The combined-slip self-aligning torque is described likewise.

This paper reports how numerical simulation can be used as a tool to guide vehicle design with respect to brake cooling demands. Detailed simulations of different brake cooling concepts are compared with experimental results. The paper consists of two parts. The first part places the emphasis on how to model the flow inside and around the brake disc. The boundary layer and the pumping effect is investigated for a ventilated single rotor. The numerical results will be compared to experimental results. In the second part, an engineering approach is applied in order to rank different technical solutions on a Volvo S80 vehicle in terms of brake cooling and aerodynamic drag. The results from the free brake disc simulations indicate that the tangential velocity can be predicted with high accuracy, e.g. standard k-ε model with prism near wall cells typically within 4% of measured data.

SI Engine knock is caused by autoignition in the unburnt part of the mixture (end-gas) ahead of the propagating flame. Autoignition of the end-gas occurs when the temperature and pressure exceeds a critical limit when comparatively slow reactions-releasing moderate amounts of heat-transform into ignition and rapid heat release. In this paper the difference in the heat released in the end-gas-by low temperature chemistry-between lean, rich, stochiometric, and stoichiometric mixtures diluted with cooled EGR was examined by measuring the temperature in the end-gas with Dual Broadband Rotational CARS. The measured temperature history was compared with an isentropic temperature calculated from the cylinder pressure trace. The experimentally obtained values for knock onset were compared with results from a two-zone thermodynamic model including detailed chemistry modeling of the end-gas reactions.

This paper describes the OBD II System in the Volvo 850 Turbo. This car is equipped with a new engine, a 5-cylinder, in-line, 2.3 liter design, mounted transversely in the car. The system uses the new Bosch Motronic M4.3 Powertrain Control Module, The realization of the new diagnostic regulation is described with examples. The development of new, specialized diagnostic equipment is also described.

Frontal collisions account for the majority of car accidents. Regulations have been in effect since the late sixties, aiming at assuring a basic safety performance for cars in this type of crash. From a legislative point of view tests as e.g. FMVSS 208 are about to be complemented by other frontal impact configurations. Two of the reasons behind this is to allow assessment also of asymmetric loads to the vehicle front and the level of passenger compartment intrusion. This paper offers a comparison of different frontal crash tests, including Volvo's Severe Partial Overlap Collision (SPOC) and offset tests against a deformable barrier. The methods are evaluated with respect to their results, both from a dummy performance point of view and based on car deformation characteristics. Also, the practicability and possible effect on vehicle designs are discussed.

Flexible car body production, including prototyping, is one answer to the market targets where customers ask for an increasing number of models / variants and shorter lead time. The in-house interests of car builders are, besides investment and manpower flexibility, also improved product quality. Quality in body in white is mainly related to geometry (= high precision), to make sure that the final assembly shops will have the right conditions to keep customers satisfied (flush in doors, hood, fenders etc.). The consequences are that both the product and the process equipment have to be in a stable condition to guarantee low spread in the complete car-body. CAD technology is one of the keys to reach this goal, where: Off-line tooling Off-line programming Flow simulation Measurement strategy, off-line / in-line are the main powerful tools to reduce lead time as well as costs.

OBD II established a new level for automotive on board diagnostics. This concept, state of the art, is already introduced on the market, MY-94, ( reference 1). We will now go one step further by introducing the Diagnose 2 Concept. With D2 we connect almost all ECU's in a vehicle to the same diagnostic communication bus, connected to the same pin, (pin 7 in the J1962 connector). It will now be possible to hook up to all ECU's with one connector, the OBD II connector inside the passenger compartment, (this will not be any problem for a properly programmed OBD II Scan Tool, as it only will look for the emission related ECU's).

Legal producer responsibility for end-of-life vehicles will be introduced in Sweden 1998. In an ongoing 1-year project the conditions tor a producer-dismantler network are developed, aiming at increased recovery. About 5000 cars of 5 makes are treated by 30 dismantlers. Producers (manufacturers and importers) not actively involved participate in an information feedback program. The producer-initiated project develops interaction with existing expertise and experience of management of sometimes conflicting interests. Urgent questions are cost-effectiveness, recovery methods and markets, dismantling instructions, and monitoring methods. The project is expected to expand into a national network of producer-contracted dismantlers, with possibilities for even further expansion.

Each year Volvo Car Corporation invests about 10 per cent of its turnover in product development. One tenth of this amount is reserved for advanced research projects, or high risk projects. Volvo LCP (Light Component Project) 2000 is one of these projects and a preparation in technology and competence for the year 2000. In addition to broad theoretical know-how concerning new materials, alternative drive lines, new production methods, etc, the LCP study has resulted in four road-going experimental cars. The project which started in mid 1979 was presented to the public in October 1983 after a year's testing and evaluation of the car, its sub-systems and design solutions. This paper is a description of the project work. Another paper ‘Magnesium in the Volvo LCP 2000’, deals more specifically with the results of the LCP material studies.

This paper describes some of the engineering situations encountered during the development of a three point belt for the rear center seating position in a sedan car. The belt will be sold as an accessory for the after market. The reinforcement of the parcel shelf to achieve a sufficiently strong anchorage for the retractor and the geometrical locations of the belt anchorages are presented. The conflict between the geometrical requirements, the design and the visibility will be focussed. The need for updated requirements for belt installations in the rear center seating position will be pointed out. Data from the performed tests show that all demands from regulations and “in-house” requirements are fulfilled.

This paper reports an one–dimensional modeling procedure of the hot spot autoignition with a detailed chemistry and multi–species transport in the end gas in an SI engine. The governing equations for continuity of mass, momentum, energy and species for an one–dimensional, unsteady, compressible, laminar, reacting flow and thermal fields are discretized and solved by a fully implicit method. A chemical kinetic mechanism is used for the primary reference fuels n–heptane and iso–octane. This mechanism contains 510 chemical reactions and 75 species. The change of the cylinder pressure is calculated from both flame propagation and piston movement. The turbulent velocity of the propagating flame is modeled by the Wiebe function. Adiabatic conditions, calculated by minimizing Gibb's free energy at each time step, are assumed behind the flame front in the burned gas.

This article describes an expert system for objective rating of subjective characteristics like driving comfort. The system uses radial basis neural networks that can be trained on any dynamic properties, for example acceleration. Training and retraining can be done in real-time. The system includes a measure of the reliability of automatic judgement, which can be used to signal when new training may be necessary. The article shows in detail how the system has been used to automatically judge gearshift comfort for automatic transmission. Tests indicate that the system's accuracy and consistency are as good as one of Volvo's best experts.

Under a global impulse for less man-made emissions, the automotive manufacturers search for innovative methods to reduce the fuel consumption and hence the CO2-emissions. Aerodynamics has great potential to aid the emission reduction since aerodynamic drag is an important parameter in the overall driving resistance force. As vehicles are considered bluff bodies, the main drag source is pressure drag, caused by the difference between front and rear pressure. Therefore increasing the base pressure is a key parameter to reduce the aerodynamic drag. From previous research on small-scale and full-scale vehicles, rear-end extensions are known to have a positive effect on the base pressure, enhancing pressure recovery and reducing the wake area. This paper investigates the effect of several parameters of these extensions on the forces, on the surface pressures of an SUV in the Volvo Cars Aerodynamic Wind Tunnel and compares them with numerical results.

This paper presents results from a quantitative characterization of the NO distribution in a SI engine fueled with a stoichiometric iso-octane/air mixture. Different engine operating conditions were investigated and accurate results on NO concentrations were obtained from essentially the whole cylinder for crank angle ranges from ignition to the mid expansion stroke. The technique used to measure the two-dimensional NO concentration distributions was laser induced fluorescence utilizing a KrF excimer laser to excite the NO A-X (0,2) bandhead. Results were achieved with high temporal and spatial resolution. The accuracy of the measurements was estimated to be 30% for absolute concentration values and 20% for relative values. Images of NO distributions could also be used to evaluate the flame development. Both the mean and the variance of a combustion progress variable could be deduced.

Research on frontal collisions has been the theme of numerous papers and publications over the years. The relevance of the subject is clearly demonstrated by different accident studies. The analysis shows that apart from the traditional high speed full frontal barrier impact, it is also necessary to simulate tests at lower speeds and partial overlap collisions at high speeds. This paper describes one of the frontal impact situations, the Severe Partial Overlap Collision (SPOC); accident analyses leading to a test method and its application by description of a new car design concept.