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An automotive heater hose is a nylon-reinforced rubber component which has pressurized coolant flows from engine to Heating, Ventilation Air Conditioning (HVAC) unit and connected at either end using spring or worm clamps. One of the important design failure modes to study is the coolant leakage during hose slip-off scenario that can lead to walk-home failures. Overall dimensional variations, assembly loads and part variations can lead to such scenarios which are crucial to investigate using statistical approach for the robust design. To establish this, an experimental setup was conducted, and an equivalent CAE model was developed using Abaqus Standard. The Finite Element model comprised of an engine union pipe, a rubber heater hose and a spring clamp on the engine side of the vehicle. A suitable hyperelastic model for nylon-reinforced rubber and friction values were used to correctly represent the behavior of heater hose with adjoining steel components.

The Body Control Module (BCM) is a very large integration site for vehicle features and functions (e.g., Locking, Alarms, interior lighting, exterior lighting, etc…). Every few years the demand to add more feature/functions and integrate more vehicle content increases. The expectation of the 2013 MY (model year) BCM, was to double the feature content and use it globally. The growth in 3 years of feature/function content was huge number that grew from 150 to over 300. This posed a major challenge to the software development team based on the methods and process that were deployed at the time. This paper cites the cultural and technology changes that were overcome when Ford Motor Company partnered with Tata Consultancy Services to help manage and define this new software engineering development methodology. The process of getting from a vague description of a new body module feature to a saleable product, presents several very challenging problems.

Squeak and Rattle (S&R) noise in automotive vehicle components is a direct measure of vehicle build quality. With the recent advances in electric propulsion technology the cabin interior has become even more quieter, but S&R remains one of the main noise issues inside the cabin. Consumer surveys such as by J D Power shows that instrument panel, floor console and glove box latch mechanism are some of the most prominent sources of vehicle interior noise. The commonly used design for console lid latch consists of latch pawl preloaded against the console bin in closed condition. The goal of design is to optimize the preload such that the latch remains in contact with the bin under all operating conditions. But inadequate design, poor manufacturing quality control and material degradation causes the loss of preload. Hence, S&R noise emerges due to friction or impact between the parts which induces undesirable vibration and noise.

High energy and power density Lithium-ion batteries are used as energy storage devices for indispensable applications ranging from cell phones to hybrid electric vehicles, unmanned aerial vehicles and commercial passenger aircrafts. To monitor the health of the battery and its various performances, it is crucial to understand the electrochemical behavior of the battery. The Doyle-Fuller-Newman (DFN) model is a popular electro-chemistry-based model, which characterizes the solid and electrolyte diffusion dynamics in the battery and predicts current/voltage response. However, the DFN model requires many parameters that need to be estimated to obtain an accurate battery model. In this article, an electro-chemistry based cell model is developed using GT-AutoLion to simulate and validate the performance for two different commercially available Lithium Iron Phosphate (LiFePO4) and Nickel Cobalt Aluminum (NCA) cells.

Numerical simulation of lithium-ion batteries (LIB) has become extremely vital in the understanding of thermal behaviour of LIBs to develop active and passive battery thermal management systems. The LIB is popular in consumer electronics. Beyond consumer electronics, the LIB is also growing in popularity for the automotive applications such as hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) due to its high energy density, high voltage, and low self-discharge rate. High amount of heat generally gets developed during charge and discharge of LIB based on the c-rate at which it is being discharged or charged. Hence, there should be a mechanism to understand the thermal behaviour of these cells. Thus, in this paper a numerical procedure has been developed to model electrochemical-thermal behaviour of commercially available 21700 Li-ion cells. NewmanP2D approach is used to arrive at electrochemistry performance of Li-ion cell and pack.

Oven exposure testing is a standard benchmark (where Li-ion cells are exposed to higher temperature) that Li-ion cells must pass to get approval for sale by the regulating bodies. These tests are designed to ensure the safety of battery user as the Li-ion batteries are vulnerable to abuse conditions. However, these tests can be both costly and time consuming. Hence, development of simulation capabilities which can replace the physical test to a certain extent helps both battery manufacturers and OEMs not only in the cost cutting but also to optimize the critical parameters which can directly influence the safety criterions. In this paper, a numerical model of 18650 NCM Li-ion cell in an oven test condition is developed to study the thermal runaway, cell venting, internal pressure buildup, and gas flow behavior using ANSYS FLUENT commercial software.

Hyper-elastic seals are extensively used in automotive applications for sealing various joints in assembly. They are also used in sealing battery packs. They are used in various sizes and shapes. Most of the gaskets used are solid gaskets. Hollow gaskets are also being used. Hollow gaskets typically have a fluid like air trapped inside. Analyzing these hollow gaskets also requires involving the physics of the fluid inside. The trapped fluid affects the performance of the gasket like contact pressure and width. Objective of this study is to analyze the hollow gasket performance including the effect of air trapped inside. The effect of air on performance of the hollow seal is also studied. Fluid Cavity capability in ABAQUS was selected after literature study to simulate the effect of trapped fluid (Air) on seal performance.

Felt-based dash panel insulation materials have traditionally been used as a sound barrier between the engine and passenger compartments in a vehicle to reduce the transmission of engine noise to the occupant space. Their structural performance has been mainly ignored due to the typically low stiffness and strength characteristics. Consequently, studies of the acoustic properties of these materials have been found in literature while no information was found on their mechanical behavior especially in dynamic loading conditions. More stringent requirements for occupant and pedestrian safety imposed by government regulations and the position of these materials in the impact zones of pedestrian head impact have brought attention to the material contribution to the energy absorption during the impact and the need to assess the mechanical properties of these materials.

The world is moving towards E-mobility solutions and Battery Electric Vehicles (BEVs) are the main enabler towards it. Li-ion cells are the fundamental building block of any BEVs. There are three common types of Li-ion cell design i.e., cylindrical cells, Prismatic Cells and Pouch cells. Ensuring safety of BEVs are critical to gain customer trust and acceptance over Internal Combustion Engine (ICE) vehicles. EV fire is found to be one of the major concerns related to using higher energy batteries. During a crash event, Post-Crash Electrical Integrity of the BEV is to be ensured and hence primary focus is on mitigation of Li-ion cell internal short circuit. It has been seen in prior published articles that cell internal short circuit can be triggered by physical intrusion of cell. This paper primarily focusses on simulating the mechanical behavior of cylindrical cell under various crush conditions.

Premium instrument panels (IPs) contain passenger airbag (PAB) systems that are typically comprised of a stiff plastic substrate and a soft ‘skin’ material which are adhesively bonded. During airbag deployment, the skin tears along the scored edges of the door holding the PAB system, the door opens, and the airbag inflates to protect the occupant. To accurately simulate the PAB deployment dynamics during a crash event all components of the instrument panel and the PAB system, including the skin, must be included in the model. It has been recognized that the material characterization and modeling of the skin tearing behavior are critical for predicting the timing and inflation kinematics of the airbag. Even so, limited data exists in the literature for skin material properties at hot and cold temperatures and at the strain rates created during the airbag deployment.

The battery cell unit and battery module constitute the building blocks for the battery pack in an electric vehicle. It is important to rigorously understand the vibration induced response of the battery pack as it is a prerequisite for the safety of an electric vehicle. An accurate finite element (FE) model plays a key role in predicting the dynamic response of the battery pack simulation. In this paper, finite element analysis (FEA) results are compared with the experimental set up of the battery components and a 60-cell battery module. Using orthotropic elastic constants instead of isotropic properties to model the fiber reinforced polymer (FRP) made battery components produced better modal results correlation. Modal frequency values for the brick components have been improved by 25% to 50%. For the battery module, swapping of mode shape behavior is observed between finite element model and experimental results.

This paper is a continuation of previously published technical paper SAE 2022-01-0314. The preceding work described an analytical methodology to predict the vehicle interior trim squeak and rattle issues upfront in the design cycle using a “relative displacement” or “contact force” metric; the methodology was implemented on the center floor console armrest latch using a linear finite element model. The work is logically extended to predict the squeak and rattle issues quantitatively using now an “acoustic noise” metric, this enables a direct comparison with the physical test results and helps to further refine the design best practices. This approach combines Finite Element Method (FEM) and Boundary Element Method (BEM) to estimate structural vibration response and acoustic sound pressure respectively.

With advancement and increase in usage of Li-ion batteries in sectors such as electronic equipment’s, Electric Vehicles etc battery lifetime is critical for estimation of product life. It is well known that temperature and voltage strongly influence the degradation of lithium-ion batteries and that it depends on the chemical composition and structure of the positive and negative electrodes. Lithium batteries are continuously subjected to various load cycles and ambient temperatures depending on application of battery. Thus, in many applications Cycle aging could be the main contributor or factor for battery degradation, thus reduction in life of product. Thus, there is strong need for researchers and engineers to help improve life of cells or batteries being used in electric vehicles. In this present work, cycle aging of commercial 18650 cell is studied at ambient temperature. Experimental data shows that about nearly 20 % cell capacity degrades at ambient temperature.

Battery Electric Vehicles (BEVs) are becoming more competitive day by day to achieve maximum peak power and energy requirement. This poses challenges to the design of Thermal Interface Material (TIM) which maintains the cell temperature and ensure retention of cell and prevent electrolyte leak under different crash loads. TIM can be in the form of adhesives, gels, gap fillers. In this paper, TIM is considered as structural, and requires design balance with respect to thermal and mechanical requirements. Improving structural strength of TIM will have negative impact on its thermal conductivity; hence due care needs to be taken to determine optimal strength that meets both structural and thermal performance. During various crash conditions, due to large inertial force of cell and module assembly, TIM is undertaking significant loads on tensile and shear directions. LS-DYNA® is used as simulation solver for performing crash loading conditions and evaluate structural integrity of TIM.

As the world is moving towards greener energy solutions, there is a clear transition seen from ICE to EV powertrain solution. The cost of vehicle is primarily controlled by battery pack as it is high capital intense. Though Li-Ion battery is a very promising technology in terms of energy storage and long-term performance, safety of battery is a concern. Battery can undergo self-fire/ thermal runaway due to several factors like aging, internal short, overcharging etc. A numerical investigation is carried out for a conceptual 10S1P prismatic battery pack to model the nail penetration using commercial ANSYS Fluent tool. Vent gas generation has been modelled and its convective effects on Thermal runaway were studied. Vent gas generation is supported through a user defined function which calculates the amount of flow rate that vent gas encounters during thermal runaway.

Electric Vehicles are rapidly growing in the market yet various doubts on success of its adaptation were noted all along the globe. On the question part range is one of the major attribute; however, range anxiety has greatly inspired manufacturers to explore new practices to improve. One of the most important components of an electric vehicles (EV) is the battery, which converts chemical energy to electrical energy thereby liberating heat energy as the loss. When this heat energy loss is high, the energy available in the battery for propulsion is reduced significantly. Additionally, with a higher heat loss in the battery, system is prone to failure or reduced mileage. Therefore, controlling/maintaining system temperature under safe usable limits even during harsh conditions is critical. Simple reduction in energy consumption of electrical cooling/heating devices used with regenerative energy techniques can greatly help in range improvement.

Electric car markets experience exponential growth. As per IEA battery electric vehicles sales exceeded 10 million in 2022 [1] . There is projection from IEA that EV sales will touch 40 million mark by 2030, major contribution from China (12 m) and Europe (13.3 m) regions [2]. This growth projection attributed to many global factors, government policies, automakers commitment, climate change, etc. There is a massive push from global institutions and automobile community for transition to electric mobility. There is a 66% likelihood that the annual average near-surface global temperature between 2023 and 2027 will be more than 1.5°C above pre-industrial levels for at least one year. There is a 98% likelihood that at least one of the next five years, and the five-year period, will be the warmest on record [3]. Hence transition is imperative to reduce greenhouse gases and adhere to climate change commitments. Today EVs are not popular as ICE.

The automotive seat has undergone significant advancements in technology due to changing customer demands, levels of autonomy and vehicle regulations. These advancements have presented both opportunities and challenges in creating a pleasant experience for customers by ensuring optimal seat comfort and a joyful human experience. Seats are always being built to accommodate different percentiles of occupant comfort requirements; original equipment manufacturers come up with various seating adjustment features. However, there is considerable variation among each percentile of occupants in how they utilize these features to achieve a comfortable seating position based on their unique preferences and circumstances. Additionally, there are variations in occupant postures due to the ways people have adapted their driving habits or styles when it comes to the way they sit.

Pulse Width Modulation or PWM has been widely used in traction motor control for electric propulsion systems. The associated switching noise has become one of the major NVH concerns of electric vehicles (EVs). This paper presents a multi-disciplinary study to analyze and validate current ripple induced switching noise for EV applications. First, the root cause of the switching noise is identified as high frequency ripple components superimposed on the sinusoidal three-phase current waveforms, due to PWM switching. Measured phase currents correlate well with predictions based on an analytical method. Next, the realistic ripple currents are utilized to predict the electro-magnetic dynamic forces at both the motor pole pass orders and the switching frequency plus its harmonics. Special care is taken to ensure sufficient time step resolution to capture the ripple forces at varying motor speeds.