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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.

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.

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.

Galvanic corrosion of high purity die cast magnesium alloys AM50 and AZ91 was examined in accelerated atmospheric corrosion testing according to Volvo STD 1027,1375 for 6 weeks involving cycling of the relative humidity between 90% and 45% in combination with intermittent immersion in one of two NaCl-solutions (0.3% or 1.0%). The exposures were performed at two different CO2 levels; 0.01% and 0.3%. The initial general corrosion rate of the AM50 alloy is 50-100% higher than that of AZ91 depending on surface preparation. The corrosion weight loss of both materials depends linearly on salt load in the investigated range. CO2 has a moderate accelerating effect, being higher with decreased salt load. Extreme value analysis was used to evaluate the deepest pit distribution around the perimeter of mounted bolts in panels of AZ91 and AM50. Quite contrary to the general corrosion results, AZ91 showed 30% deeper pits than AM50.

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.

The object with this paper is to give performance data for an ISG (Integrated Starter/Generator) which is mounted around the flywheel. With regard to weight, the ISG concept shall be competitive compared to a system with conventional components. The comparison will be based on a 48 V DC-system, and performed for a vehicle which is heavily equipped with electrical loads. The paper focuses on the electrical machine in the ISG (which is of induction type). The convertor is only covered in brief. For design of the start system, a computer program for simulation of a start sequence is used. Models implemented in the program will be discussed. A simplified equation for the load torque during cranking will be explained. For design of the generator system, two different drive cycles will be discussed. One is more related to the traditional load-balance situation during city driving, and the other related to the new load-balance obtained with the characteristic of an induction machine.

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.