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Conventional car manufacturing is extremely capital and energy-intensive. Due to these limitations, major auto manufacturers produce very similar, if not virtually identical, vehicles at very large volumes. This limits potential customization for different users and acts as a barrier to entry for new companies or production techniques. Better understanding of the barriers for low volume production and possible solutions with innovative production techniques is crucial for making low volume vehicles viable and accelerating the adoption of new production techniques and lightweight materials into the competitive marketplace. Additive manufacturing can enable innovative design with minimal capital investment in tooling and hence should be ideal for low and perhaps high volume parts. For this reason, it was desired to evaluate potential opportunities in manufacturing automotive parts with additive techniques.

OEMs are investigating opportunities to reduce vehicle mass, driven by a need to meet upcoming CAFE targets, increase the range and reduce battery size of EVs. A number of lightweight materials including high strength steels, aluminum alloys, plastics and composites are now in production. To facilitate development of corporate R&D and commercialization plans for new materials, it is beneficial to understand the current manufacturing costs for production components, and their impact on piece price at different volumes. This paper investigates design and cost impact of light-weighting with respect to front door and floor assembly of Toyota Corolla and BMW i3. Toyota Corolla has a traditional steel body and is sold in high volumes while BMW i3 has relatively low annual sales and is primarily made of composite, aluminum and plastic parts.

There is much interest and debate on which advanced vehicle technologies will be common in the future. Public expectations seem to be running high with great promise of non-polluting, high efficiency vehicles. For the vehicles to reach high volume production though, the characteristics of these vehicles will need to meet customer demands for price, performance, driveability and comfort. The ideal propulsion system solution may well be different for the various vehicle applications (SUV, passenger car, city bus) as well as in different world markets. Currently there appears to be a significant divide between the benefits of hybrid vehicles and the incremental price consumers may be willing to pay. This raises the question as to what type of hybrids will be seen on the roads in the future. This paper reviews the future advanced vehicle concepts and focuses on the probable prime candidate for near term mass market - the mild hybrid.

In order to meet the legislated emissions levels, future diesel engines will likely utilize cooled exhaust gas re-circulation (EGR) to reduce emissions. The addition of the EGR cooler to the conventional vehicle coolant system creates several challenges. Firstly, the engine cooling system flow and heat rejection requirements both increase as it is likely that some EGR will be required at the rated power condition. This adversely affects packaging and fuel economy. The system design is further complicated by the fact that the peak duty of the EGR cooler occurs at part load, low speed conditions, whereas the cooling system is traditionally designed to handle maximum heat duties at the rated power condition of the engine. To address the system design challenges, Ricardo have undertaken an analytical study to evaluate the performance of different cooling system strategies which incorporate EGR coolers.

Tools for the design and evaluation of engine water pumps have been developed. These tools range from textbook calculations to 3-dimensional computational fluid dynamics methods. The choice of the tools or the combination of tools used is usually dependent upon production timelines, rather than technical merit. Therefore, the strengths and weaknesses of each of the tools must be understood, and each tool must be validated for its specific purpose, then used appropriately to aid in the design or development of a water pump suitable for production. This study was carried out to evaluate three approaches: a proprietary Ricardo approach based on 1-dimensional analysis and correlations, a 3-dimensional computational fluid dynamics approach, and a conventional prototype manufacture and test iteration approach. The analytical results were correlated to experimentally obtained pressure rise, mass flow rate, and impeller speed data.

As specific engine power output increases so does the heat rejected to the coolant. The resulting need to increase radiator size is counter-productive due to the lack of package space, and a strong desire to reduce, not increase, vehicle drag. Current tendency is to size the radiator to reject sufficient heat at extreme operating conditions (full engine power, high ambient). However, this “oversized” cooling system may only be needed by a small number of vehicles. A better approach could be to size the radiator for the majority, but not all, operational conditions and manage the coolant temperature by actively controlling coolant flow and engine output. This will need to be done without compromising durability or driveability. This approach sounds highly beneficial in principle, but how sound would it be in practice ? The authors have investigated the feasibility of active control by considering the details of radiator performance and engine heat rejection.

A flow and heat transfer model of an engine lubrication system has been developed in order to predict sump oil temperature and study heat transfer mechanisms within the lubricating oil circuit. The objective was to develop the capability of simulating all the energy transfers between the oil and the combustion process, the engine coolant, and the engine bay air. The model developed in this study simulates a V8 spark ignited engine. Included in this simulation is a bearing model for friction heat generation, a combustion heat input model, and component models for each key heat transfer site in the lubricating oil circuit. The model predicts sump oil temperatures under different engine operating conditions and simulation results were compared to test data with good agreement. The sensitivity of oil temperature to engine speed, engine load, coolant temperature, piston friction, bearing heat energy generation, piston design, water jacket depth, and oil flow rate(s) was studied.

The traditional approach for vehicle thermal development relies heavily on experimentation and experience. A virtual vehicle would be very beneficial in providing upfront engineering support which should lead to time and cost savings. To realize a useful model, the authors have based their approach on experimental data and correlations for each significant vehicle component. The vehicle has been divided into five linked modules representing powertrain cooling and cab climate. The paper describes the approach taken for each module and shows that good agreement can be found between model predictions and actual measurements.