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Systems engineering is not a new discipline for todays automotive OEMs and suppliers. So, why is it that many feel the discipline is under-utilized or not utilized at all in main-stream product development? For those that do believe systems engineering is a key activity in the development cycle, why is it common to disagree on a definition of what it is or how it manifests itself in the development cycle? If we examine the development activity of leading OEM's and suppliers in any industry, there can be no doubt that product development is a complex and intensive activity. Many disciplines are utilized with many specialized skills deployed throughout the lifecycle of the typical product, and even more so in the automotive industry. One can point to several processes that seem to indicate the presence of systems engineering, yet the ability to clearly define whether or not - and to what degree - we leverage systems engineering is still difficult.

Designing a lightweight and durable engine is universally important from the standpoints of fuel economy, vehicle dynamics and cost. However, it is challenging to theoretically find an optimal solution which meets both requirements in products such as the cylinder head, to which various thermal loads and mechanical loads are simultaneously applied. In our research, we focused on “non-parametric optimization” and attempted to establish a new design approach derived from the weight reduction of a cylinder head. Our optimization process consists of topology optimization and shape optimization. In the topology optimization process, we explored an optimal structure with the theoretically-highest stiffness in the given design space. This is to provide an efficient structure for pursuing both lightweight and durable characteristics in the subsequent shape optimization process.

This paper summarizes the Fast Fourier Transform (FFT) methodology, special equipment, set-up and testing that is recommended to properly characterize the surface of bearing journals that will not result in objectionable noise or vibration. Traditional surface profiles and finish callouts do not capture some of the key characteristics for addressing what is often the customer's greatest complaint, noise. Noise can vary based on the sensitivity of the vehicle but understanding how to accurately describe (design, test, and measure) a surface for a given vehicle can result in an optimized design and reduce process time during manufacturing. Furthermore, this paper will recommend techniques for determining the proper limits of the FFT callouts.

An ignition delay correlation was developed for a toluene reference fuel (TRF) blend that is representative of automotive gasoline fuels exhibiting two-stage ignition. Ignition delay times for the autoignition of a TRF 91 blend with an antiknock index of 91 were predicted through extensive chemical kinetic modeling in CHEMKIN for a constant volume reactor. The development of the correlation involved determining nonlinear least squares curve fits for these ignition delay predictions corresponding to different inlet pressures and temperatures, a number of fuel-air equivalence ratios, and a range of exhaust gas recirculation (EGR) rates. In addition to NO control, EGR is increasingly being utilized for managing combustion phasing in spark ignition (SI) engines to mitigate knock. Therefore, along with other operating parameters, the effects of EGR on autoignition have been incorporated in the correlation to address the need for predicting ignition delay in SI engines operating with EGR.

Acoustic comfort of automotive cabins has progressively become one of the key attributes of passenger comfort within vehicle design. Wind noise and the heating, ventilation, and air conditioning (HVAC) system noise are two of the key contributors to noise levels heard inside the car. The increasing prevalence of hybrid technologies and electrification has an associated reduction in powertrain noise levels. As such, the industry has seen an increasing focus on understanding and minimizing HVAC noise, as it is a main source of noise in the cabin particularly when the vehicle is stationary. The complex turbulent flow path through the ducts, combined with acoustic resonances can potentially lead to significant noise generation, both broadband and tonal.

In use cars often drive through the wakes of other vehicles. It has long been appreciated that this imposes a fluctuating onset flow which can excite a structural response in vehicle panels, particularly the bonnet. This structure must be designed to be robust to such excitation to guarantee structural integrity and maintain customer expectations of quality. As we move towards autonomous vehicles and exploit platoons for drag reduction, this onset flow condition merits further attention. The work reported here comprises both measurements and simulation capturing the unsteady pressure distribution over the bonnet of an SUV following a similar vehicle at high speed and in relatively close proximity. Measurements were taken during track testing and include 48 static measurement locations distributed over the bonnet where the unsteady static pressures were recorded.

The double linear damage model developed by Manson and Halford helps to determine the knee point, which is the intersection between the two straight lines. The damage to the component is then calculated based on this knee point. The new approach mentioned in this paper helps to evaluate the damage on the component in a slightly different way. It uses the knee points as mentioned by Manson and Halford and decomposes the damage to the component for Phase I & Phase II. It then uses the equivalent damage approach and establishes the damage to the component. This will be explained with an example.

Never in the history of the automotive industry has it been more critical for automakers to prove that they are capable of producing vehicles efficiently and cost-effectively. In the coming months and years there will be a growing requirement for lean product design and manufacturing strategies that will re-shape the way the automotive suppliers and OEMs conduct business. Computer-aided-design and manufacturing have become commonplace in automotive product design and manufacturing processes. These technologies enable efficiencies and quality improvements through virtual simulation and testing of kinematic designs. However, to date, there has been no ability to incorporate the process controls into these simulations. Vehicle introductions require new manufacturing processes and equipment which is typically outsourced by the OEMs to a supplier.

Today's engineers must meet program management demands within the context of the challenges facing the industry as a whole. Resource scarcity, both people and capital, is forcing the automotive industry to optimize the deployment and consumption of enterprise resources. As globally dispersed project teams become more commonplace, efficient and effective communication across geographies is critical. Market segmentation and technology are influencing how well manufacturers deliver products within performance and timing guidelines. Future success means providing global engineering teams with state- of- the- art tools and processes to unify disparate business groups in a virtual workspace -24/7. The solution to this is Product Lifecycle Management (PLM), a strategic business approach that supports collaborative creation across the enterprise and all stakeholders. PLM solutions link information from different authoring tools and others systems to the developing product configuration.

Mechatronics development continues to be a challenge for automotive OEM's and suppliers. Multi-disciplinary collaboration and development is critical, especially as architectures and solutions evolve in the automotive industry to satisfy changing needs of the customer and environment. New approaches to mobility, sustainment, and infotainment create the need for new combinations of electrical, software, mechanical, and chemical know-how. Whereas most frameworks for requirements-driven model-based design support a single discipline, what is really needed is a framework for requirements-driven model- based design that can capture the multi-disciplinary architecture of the vehicle or system. This would and allow development organizations to then further decompose the objects in support of further refinement and validation.

Advanced High-Strength Steels (AHSS) have become an essential part of the lightweighting strategy for automotive body structures. The ability to fully realize the benefits of AHSS depends upon the ability to aggressively form, trim, and pierce these steels into challenging parts. Tooling wear has been a roadblock to stamping these materials. Traditional die materials and designs have shown significant problems with accelerated wear, galling and die pickup, and premature wear and breakage of pierce punches. [1] This paper identifies and discusses the tribological factors that contribute to the successful stamping of AHSS. This includes minimizing tool wear and galling/die pick-up; identifying the most effective pierce clearance (wear vs. burr height) when piercing AHSS; and determining optimal die material and coating performance for tooling stamping AHSS.

Scuffing is one of the major problems that influence the life cycle and reliability of several auto components, including engine cylinder kits, flywheels, camshafts, crankshafts, and gears. Ferrous casting materials, such as gray cast iron, ductile cast iron and austempered ductile cast iron (ADI) are widely applied in these components due to their self-lubricating characteristics. The purpose of this research is to determine the scuffing behavior of these three types of cast iron materials and compare them with 1050 steel. Rotational ball-on-disc tests were conducted with white mineral oil as the lubricant under variable sliding speeds and loads. The results indicate that the scuffing initiation is due to either crack propagation or plastic deformation. It is found that ADI exhibits the highest scuffing resistance among these materials.

To increase sales and market position, automotive OEMs must have comprehensive strategies for developing innovative products while continuing to reduce costs, increase quality and accelerate time to market. One of the strategies that can help them to achieve these objectives is strategic modularity. A modularization strategy can help automakers reduce cost and time to market, as well as improve quality and launch readiness. While a significant number of OEMs are adopting modularity strategies, the realization of benefits has been, for many OEMs, limited in scope and scale. These limitations are due to: Process issues in managing dependencies across multiple programs and platforms; Measurements which discourage modularity adoption, together with an inability to measure enterprise costs; Organizational issues associated with siloed structures, a lack of clear roles and responsibilities, and the management of disparate groups across the extended enterprise.

The development of new vehicle is becoming increasingly complex: proliferation of on-board electronics, development of hybrid advanced powertrain technologies, globalization of design and production, to name a few. At the same time, companies are straining constantly to better meet consumer desires while reducing time to market and production costs. Definitely a tough challenge! The ever growing amount of data (both in variety and in number of sources) that the enterprise generates is central to this situation. Compiling and processing this data efficiently is easier said than done. And failure to do so can lead to critical business opportunities being lost! A solution exists. It comes from the web where an innovative approach was indeed mandatory to cope with the billions of documents to search. It is called “search technology” and is engrained in the DNA of EXALEAD.

Government regulations and consumer needs are driving automotive manufacturers to reduce vehicle energy consumption. However, this forms part of a complex landscape of regulation and customer needs. For instance, when reducing aerodynamic drag or vehicle weight for efficiency other important factors must be taken into account. This is seen in vehicle bonnet design. The bonnet is a large unsupported structure that is exposed to very high and often fluctuating aerodynamic loads, due to travelling in the wake of other vehicles. When travelling at high speed and in close proximity to other vehicles this unsteady aerodynamic loading can force the bonnet structure to vibrate, so-called “bonnet flutter”. A bonnet which is stiff enough to not flutter may be either too heavy for efficiency or insufficiently compliant to meet pedestrian safety requirements. On the other hand, a bonnet which flutters may be structurally compromised or undermine customer perceptions of vehicle quality.

Design of HVAC system plays an important role in acoustic comfort for passengers. With automotive world moving towards electrical vehicles where powertrain noise is low, designing low noise HVAC system is becoming more important. For an automobile manufacturer, ability to predict the production vehicle cabin noise at the early design stage is important as it allows more freedom for design changes, which can be incorporated in the vehicle at lower cost. Although HVAC prototype and system level testing at early design stage is possible for noise estimation but flow field is not visible in test that makes difficult to improve design. CFD simulation can provide detailed information on flow field, noise source strength and location. But in such a simulation, accurate prediction has been a challenge due to the inability of CFD tools to model acoustic absorptive characteristics of interior walls of cabin.

It is particularly easy to get tunnel vision as a domain expert, and focus only on the improvements one could provide in their area of expertise. To make matters worse, many Original Equipment Manufacturers (OEMs) are silo-ed by domain of expertise, unconsciously promoting this single mindedness in design. Unfortunately, the successful and profitable development of a vehicle is dependent on the delicate balance of performance across many domains, involving multiple physics and departments. Taking for instance the design of a Heating, Ventilation & Air Conditioning (HVAC) system, the device’s primary function is to control the climate system in vehicle cabins, and more importantly to make sure that critical areas on the windshield can be defrosted in cold weather conditions within regulation time. With the advent of electric and autonomous vehicles, further importance is now also placed on the energy efficiency of the HVAC, and its noise.

The development process of a water pump impeller used on a sport utility vehicle engine is described. A review of the design process is presented in this paper including the computer-aided flow analysis together with testing procedures. By computer modeling, one can estimate the coolant flow characteristics of a given impeller blade shape for providing increased cooling performance and improved efficiency on the engine. It also provides directions for the improved design. The test data are used specifically to confirm the analysis results.

In an effort to improve the dent resistance of exterior body panels at reduced steel thicknesses, some automobile manufacturers have pursued the application of bake hardenable steels. Unfortunately, bake hardenable steels have only been available as cold rolled or with electro-zinc or electro zinc/iron coatings. This situation has been a deterrent for those automobile manufacturers that prefer the use of hot dip galvanneal coatings. Recently, the interest in hot dip galvanneal bake hardenable steels has led to the investigation and development of this more advanced steel grade. This paper presents the results of a stamping trial and dent testing on three exposed hot dip galvannealed materials; i) Regular Ultra Low Carbon (ULC), ii) Rephosphorized ULC, and iii) Rephosphorized Bake Hardenable ULC steel.

For fuel cell vehicles, it is essential that the hydrogen tank be both compact and have sufficient hydrogen to ensure reasonable driving range for which there is a need to pressurize the hydrogen in the tank at levels much higher than that of atmospheric pressure. Furthermore, fast filling is an important consideration in order to minimize time to refuel hydrogen in the tank. In this article, we investigate a Computational Fluid Dynamics (CFD) methodology to see whether we can simulate the fast filling of the hydrogen tank. We performed simulations on an existing validation case using coupled simulation approach between the PowerFLOW® flow solver and PowerTHERM® the thermal solver. For an accurate simulation at elevated pressure levels, we implemented a real gas behavior that is more accurate than the ideal gas equation of state for under these conditions. We observe good agreement with experimental data for both bulk and local variations in temperature.