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Simulations using computational techniques play a critical role in helping automotive industry adapt to light weighting and come up with future ready designs for maximizing the performance on cost and speed of manufacturing. As global legislation becomes increasingly stringent, light-weighting is a key element that will enable automotive OEMs to meet the emission goals towards net-zero future. Recent advancement in computational techniques like Topology Optimization have boosted the freedom of designers to reduce weight & cost of the part. This project discusses the development of computational models using physics-based software tools, and to validate the functional requirements to optimize the design using topology optimization techniques. The project also aims to reduce material consumption and manufacturing costs of the part while retaining its original stiffness.

Gasoline Particulate Filters (GPF) are widely employed in exhaust aftertreatment systems of gasoline engines to meet the stringent particulate emissions requirements of Euro 6 and China 6 standard. Optimization of GPF performance requires a delicate trade-off between fuel economy, engine performance and drivability. This results in a complex lengthy and iterative calibration development process which uses a lot of hardware resources. To improve the calibration process and reduce hardware testing, physics-based modeling of the GPF system is used. A 1-D chemical model supplemented with 3D CFD solver is utilized to evaluate pressure drop and soot burning performance characteristics of the GPF under engine dynamometer test conditions. The chemical kinetics of soot burning for the 1D model is developed using test data obtained from well controlled laboratory environment.

Implementing stringent emission norms and fuel economy requirement in the coming decade will be very challenging to the whole automotive industry. Aerodynamic losses contribute up to 13% to 22 % of overall fuel economy and aerodynamicists will be challenged to have optimum content on the vehicle to reduce this loss. Improving Aerodynamic performance of ground vehicles has already reached its peak and the industry is moving towards active mechanisms to improve performance. Calibrating or simulating these active mechanisms in the wind tunnel or in Computational Fluid Dynamics (CFD) would be very challenging as the model complexity increases. Computationally expensive CFD models are required to predict the transient behaviors of model complexity.

The market for electric vehicles and hybrid electric vehicles is expected to grow in the coming years, which is increasing interest in design optimization of electric motors for automotive applications. Under demanding duty cycles, the moving part within a motor, the rotor, may experience varying stresses induced by centrifugal force, a necessary condition for fatigue. Rotors contain hundreds of electrical steel laminations produced by stamping, which creates a characteristic edge structure comprising rollover, shear and tear zones, plus a burr. Fatigue properties are commonly reported with specimens having polished edges. Since surface condition is known to affect fatigue strength, an experiment was conducted to evaluate the effect of sample preparation on tensile and fatigue behavior of stamped specimens. Tensile properties were unaffected by polishing. In contrast, polishing was shown to increase fatigue strength by approximately 10-20% in the range of 105-107 cycles to failure.

Rapidly enhancing engineering techniques to manufacture components in quick turnaround time have gained importance in recent times. Manufacturing strategies like Additive Manufacturing (AM) are a key enabler for achieving them. Unlike traditional manufacturing techniques like injection molding, casting etc.; AM unites advanced materials, machines, and software which will be critical for the fourth industrial revolution known as Industry 4.0. Successful application of AM involves a specific combination and understanding of these three key elements. In this paper the AM approach used is Fused Deposition Modelling (FDM). Since material costs contribute to 60% of the overall FDM costs, it becomes a necessity to optimize the parts. This paper reports the case studies of 3D-printed Automotive Fixtures which utilize computational methods (CAE), topology optimization and FDM constrains (build directions) to manufacture the part.

Shared Mobility is changing mobility trends of Automotive Industry and its one of the Disruptions. The current vehicle customer usage and life of components are designed majorly for personal vehicle and with factors that comprehend usage of shared vehicles. The usage pattern for customer differ between personal vehicle, shared vehicle & Taxi. In the era of Autonomous and Shared mobility systems, the customer usage and expectation of vehicle condition on each & every ride of vehicle will be a vehicle in good condition on each ride. The vehicle needs systems that will guide or fix the issues on its own, to improve customer satisfaction. We also need a transformation in customer behavior pattern to use shared mobility vehicle as their personal vehicle to improve the life of vehicle hardwares & reduce warranty cost. We will be focusing on Vehicle Closure hardware & mechanisms as that will be the first and major interaction point for customers in vehicle.

Multi-layered, high-density polyethylene (HDPE) fuel tanks are increasingly being used in automobiles due to advantages such as shape flexibility, low weight and corrosion resistance. Though, HDPE fuel tanks are perceived to be safer as compared to metallic tanks, the material properties are influenced by service temperature. At higher temperatures (more than 80oC), plastic fuel tanks can soften, sag and eventually spill out the fuel, while the extreme cold (less than -20°C) can lead to potential cracking problems. Damage may also occur due to accidental drop while handling or due to an impact from a flying shrapnel. This can be catastrophic due to flammability of the fuel. The objective of this work is to characterize and develop a failure model for the plastic fuel tank material to simulate damage and enhance predictive capability of CAE for chassis and safety load cases.

Advance Active Safety Systems play a preventive role in mitigating crashes and accidents by providing warning, additional assistance to the driver and maneuverability of vehicle by itself. Some of the features include forward collision warning system and lane departure warning system activate a warning alert when potentially dangerous situations are detected. These active safety features present in developed markets work with Fusion based algorithm combining Radar, Lidar, Camera, Ultrasonic sensor’s input. Application of these algorithms are Intelligent Cruise Control, Collision avoidance, parking assistance, identify pedestrian etc. The complexity of the algorithm, cost of the control unit and road infrastructure are hindrance to emerging market. The solution presented in this paper is towards camera-based solution, describing the method to determine the predictive path, that is obstacle free space and use the predictive space to navigate or steer.

A virtual 'model' is generally a mathematical surrogate of a physical system and when well correlated, serves as a basis for understanding the physical system in part or in entirety. Drive Quality (DQ) defines a driver's 'experience' of a blend of controlled responses to an applied input. The 'experience' encompasses physical, biological and bio- chemical perception of vehicular motion by the human body. In the automotive domain, many physical modeling tools are used to model the sub-components and its integration at the system level. Physical Modeling requires high domain expertise and is not only time consuming but is also very 'compute-resource' intensive. In the path to achieving 'vDQP (Virtual Drive Quality Prediction)' goal, one of the requirements is to establish 'well-correlated' virtual environments of high fidelity with respect to standard test maneuvers. This helps in advancing many developmental activities from a Analysis, Controls and Calibration standpoint.

A study on the effect of indenting power-law shaped profiles on the flexible structures for investigating the vibration damping characteristics using computational simulation method is discussed. The simulation results are checked to see the impact of such features on the damping behavior of flexible structures responsible for radiating noise when excited with fluctuating loads. Though the conventional remedies for solving Noise and vibration issues generally involves tuning of structure stiffness or damping treatment this paper gives an insight on the idea of manipulation of elastic waves within the flexible structure itself to minimize the cross-reflections of the mechanical waves. The simulation studies mentioned in this paper not only hovers over the effectiveness of such features but also will be helpful for the engineers to look through a different perspective while solving N&V issues using simulation tools.

Aerodynamic performance of on-road vehicle can be improved by using portable enablers on rear portion of the vehicle which can be attached or detached by the owner himself. Objective of this study is to explore the possibility of using such portable enablers to substantially reduce the drag of the vehicle. Enablers with specific convex shapes are created on various positions of rear portion of vehicle and simulated with CFD solver FLUENT. Compact sedan vehicle was considered in this study. Preprocessing is performed and specific fluid domains are captured. Generally, aerodynamic enablers are integrated parts of the vehicle. This paper emphasizes on consideration of portable enablers which can be used while cruising for longer distances. Drag improvement of ΔCD = 0.006~0.009 was achieved by introducing the specific enabler based on its position, shape and dimension. This paper also suggests methods of attachment of portable enabler to the vehicle.

Simple planetary gears are widely used in automobile industry due to their compact design and high power density. A simple planetary gear set consists of a Sun gear, Ring gear, Planets and Carrier which houses planet gears. Mounting of planet pinions on carrier is through pins which is supported on needle roller bearings. A process called staking is used to assemble the pinion pins on to the carrier. Pinion pins have a staking region which after assembly expands outward into staking groove on the carrier to prevent axial movement of the pins. Design of the groove plays a vital role for the fixation of planet pins and robustness a carrier. Planetary carrier staking grooves are designed to meet pinion pin retention and strength targets.

In automotive industry, many of the powertrain components (for e.g. engine head and cylinder block) are generally manufactured by a casting procedure. Secondary Dendrite Arm Spacing (SDAS) is one of the most important microstructural features in dendritic solidification of alloys (for e.g. Al-Si alloys) during the casting process. SDAS has a significant influence on the mechanical behavior of the cast aluminum components. A lower value of SDAS is desired in order to achieve better fatigue strength of the cast components which can be controlled by governing several casting parameters. For directional solidification, SDAS is dependent on various casting parameters i.e. chemical composition of the alloy, cooling rate and liquid melt treatment. During industrial casting of an alloy with predefined chemical composition, cooling rate during the mushy zone becomes the dominant parameter for controlling SDAS.

Hood closing effort under quasi-static conditions, known as static latching, is an event where the hood latch moves from secondary position to primary latched position due to external force applied by the customer to the hood. When customers close the hood slowly, it may not get latched due to insufficient force transfer to the latch thus requiring additional effort. Recent vehicle designs have the hood latch mounted further rearward than typical from the hood leading edge due to architectural challenges. Pedestrian protection (PedPro) requirements drive hood designs with reduced stiffness above the latch resulting in poor load transfer from the customer to the latch. This often results in high customer effort during quasi-static hood closing events. This additional effort may cause undesirable permanent deformation on the hood outer panel.

Planetary gear set is one of the most commonly used gear systems in automotive industry as they cater to high power density requirements. A simple planetary gear set consists of a sun gear, ring gear, planets and carrier which houses planet gears. Efficiency of a transmission is dependent upon performance of gear sets involved in power transfer to a great extent. Structural rigidity of a planetary carrier is critical in a planetary gear set as its deflection may alter the load distribution of gears in mesh causing durability and noise issues. Limited studies exist based on geometrical parameters of a carrier which would help a designer in selecting the dimensions at an early stage. In this study, an end to end automated FEA process based on DOE and optimization in Isight is developed. The method incorporates a workflow allowing for an update of carrier geometry, FE model setup, analysis job submission and post-processing of results.

The MacPherson strut is a simple and common across all automotive’s front suspension of passenger cars. It is an independent suspension type, including a single suspension arm (spring and damper), an anti-roll bar and a lower arm. The MacPherson strut must have sufficient stiffness to support cornering force and fore/aft loads. Fatigue test of MacPherson strut suspension can be done in multiple ways. Most common method is laboratory testing/rig test. The objective of laboratory testing is to validate the MacPherson strut physically for all possible real-time events. Replicating all real-time events in lab environment is a challenging task. For many years this limitation was addressed through experience, however it has often led to either over or inferior design. The expected life span of automotive components like MacPherson strut varies considerably but it can be measurable in years/miles.

In a typical ground vehicle, airflow enters engine compartment through grille and carries heat from the engine, cabin and other auxiliaries through heat exchangers such as radiator, condenser, oil cooler and charge air cooler respectively. The amount of airflow entering the engine compartment is governed by their individual resistances, the grille and engine compartment resistances. Also, this flow adds to drag and deteriorates overall aerodynamic efficiency. It is known as cooling drag which contributes to 8 to 12 percent of overall drag. Aerodynamics and Front End Air Flow (FEAF) development happens through CFD and it demands accurate heat exchanger pressure drop data which is usually obtained from supplier at very early stages of a vehicle development. Historically, this data is found to have significant variations compared to in-house test data.

This paper compares the material consumption and fire patterns which developed on four nearly identical compact sedans when each was burned for exactly the same amount of time, but with different wind speed and direction during the burns. This paper will also compare the effects of environmental exposure to the fire patterns on the vehicles. The burn demonstrations were completed at an outdoor facility in southeast Michigan on four late model compact sedans. The wind direction was controlled by placing the subject vehicle with either the front facing into the wind, or rear facing into the wind. Two of the burns were conducted when the average observed wind speed was 5-6kph and two of the burns were conducted at an average observed wind speed of 19kph.

Cellular foams have found a predominant application in automotive industry for efficient energy absorption so as to meet stringent and continuously improving vehicle crashworthiness and occupant protection criteria. The recent inclusion of pedestrian protection regulations mandate the use of foams of different densities for impact energy absorption at identified impact locations; this has paved the way for significant advancements in foam molding techniques such as dual density and tri-density molding. With increased emphasis on light-weighting, solutions involving the use of polymeric or metallic foams as fillers in hollow structures - foam encapsulated metal structures - are being explored. Another major automotive application of foams is in the seat comfort area, which again involves foams of intricate shapes and sizes. In addition, a few recently developed foams are anisotropic, adding on to the existing complexities.

Expanded Polypropylene (EPP) foams are most commonly used in automotive applications for pedestrian protection and to meet low speed bumper regulatory requirements. In today’s automotive world the design of vehicles is predominantly driven by Computer Aided Engineering (CAE). This makes it necessary to have a validated material model for EPP foams in order to simulate and predict performance under various loading conditions. Since most of the automotive OEMs depend on local material suppliers for their global vehicle applications it is necessary to understand the variation in mechanical properties of the EPP foams and its effect on performance predictions. In this paper, EPP foams from three suppliers across global regions are characterized to study the inter-supplier variation in mechanical properties.