Automotive Applications Research Articles

Hydrogen storage ability of hexagonal boron nitride

The development of hydrogen energy is capable of solving a number of important issues that modern society is facing, including global warming and various environmental impacts. Currently, there is an intensive search for natural sources of hydrogen as well as low-carbon techniques for mass production of hydrogen from natural gas, associated petroleum gas, and water. In parallel, efforts to develop technologies for the subsequent management of hydrogen are underway, and the creation of its safe and efficient storage is one of the highest priority goals. For the transportation and storage of hydrogen today, a number of solutions are offered, each of which has both positive and negative aspects. The boron nitride family of materials with high thermal and chemical stability, variability of morphologies, and flexibility of structure has been considered as a candidate for efficient hydrogen storage. This review offers to familiarize readers with the progress in the research and application of hexagonal boron nitride (h-BN), as well as BN-based materials in comparison with other materials, as promising hydrogen storage. Experimental and theoretical data obtained for different morphologies and internal structures were reviewed in relevance to the material`s sorption capacity with respect to hydrogen. Various approaches to improve the efficiency of hydrogen storage were analyzed, and the highest storage capabilities published were mentioned. Thus, BN-based materials are very promising as hydrogen storage, even for an automotive application, but the development of new mass production technologies should be carried out.

Factors Impacting the Photostability of a Roll‐to‐Roll Processed PEDOT Derivative for Flexible Electrochromic Devices

AbstractFor the use of polymeric electrochromic devices (ECDs) in architectural or automotive applications, the photostability of the electrochromic (EC) polymer is crucial for long‐term durability. In this study, the photostability of the side‐chain modified poly(3,4‐ethylenedioxythiophene) (PEDOT‐EthC6)thin films deposited by roll‐to‐roll slot‐die coating on indium tin oxide coated polyethylene terephtalate (PET‐ITO) is investigated and characterized by UV–vis and IR spectroscopy. Residual iron salt on the EC polymer layer, necessary for the in situ polymerization, and the variation of storage times between processing steps have no influence on the degradation rate during light exposure. The photostability of the thin films is 30% better in an inert atmosphere than in ambient conditions. Different long‐pass filters are applied to enhance the photostability in the colored and the bleached state. The position of the absorption edge strongly affects the photostability and visual appearance/color of the PEDOT‐EthC6 electrodes. The analysis of the CIE L*a*b* color coordinates reveals that a trade‐off between stability and a desirable color is necessary. To prevent UV degradation of the EC polymer in flexible ECDs, sputtered nickel oxide is chosen as the counter electrode material. The hybrid ECD shows no sign of degradation and loss of electrochromic performance after 350 h of light exposure.

CuFe2O4 Nanofiber Incorporated with a Three-Dimensional Graphene Sheet Composite Electrode for Supercapacitor and Electrochemical Sensor Application

The demand for regenerative energy and electric automotive applications has grown in recent decades. Supercapacitors have multiple applications in consumer alternative electronic products due to their excellent energy density, rapid charge/discharge time, and safety. CuFe2O4-incorporated three-dimensional graphene sheet (3DGS) nanocomposites were studied by different characterization studies such as X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The electrochemical studies were based on cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS) measurements. As prepared, 3DGS/CuFe2O4 nanocomposites exhibited an excellent surface area, high energy storage with appreciable durability, and excellent electrocatalysis properties. A supercapacitor with 3DGS/CuFe2O4-coated nickel foam (NF) electrodes exhibited an excellent specific capacitance of 488.98 Fg−1, a higher current density, as well as a higher power density. After charge–discharge cycles in a 2.0 M KOH aqueous electrolyte solution, the 3DGS/CuFe2O4/NF electrodes exhibited an outstanding cyclic stability of roughly 95% at 10 Ag−1, indicating that the prepared nanocomposites could have the potential for energy storage applications. Moreover, the 3DGS/CuFe2O4 electrode exhibited an excellent electrochemical detection of chloramphenicol with a detection limit of 0.5 µM, linear range of 5–400 µM, and electrode sensitivity of 3.7478 µA µM−1 cm−2.

Investigative studies on natural fiber reinforced composites for automotive bumper beam applications

The automotive sector wants lighter, recyclable, degradable, and sustainable composite materials. In the last few decades, natural fiber composite has been used in a wide range. The natural plant-based fibers are reinforced into polymeric composite materials, giving significant mechanical properties compared to conventional material. This work selects flax and sisal fibers due to higher strength and Young’s modulus. Mechanical behavior such as tensile, flexural, and impact strength are evaluated. Mechanical behavior results are considered in the simulation to determine the performance of an automotive bumper beam. The tensile strength of the flax composite is 90% higher than that of the sisal composite. Flexural strength is 17% higher in a flax composite, whereas energy absorption is nearly identical in a flax and sisal composite. The flax composite has a maximum 204.9 MPa tensile strength, 157.98 MPa flexural strength, and 45 J energy absorption. The mechanical behavior results are validated with simulation results in the ANSYS workbench for static analysis. The results indicate that the flax fiber reinforced composite with 43:57 of a flax-matrix ratio performs better as it can be used as a structural material. A morphological study shows the uniform distribution of matrix material and fiber orientation.

Impact of Aging Time on the Metallurgical Properties and Hardness Characteristics of an Al-Si-Mg-Cr Hypoeutectic Alloy Intended for Automotive Applications

This research investigates the microstructural evolution and mechanical properties of LM25 (Al-Si-Mg) alloy and Cr-modified LM25-Cr (Al-Si-Mg-Cr) alloy. Microstructural analysis reveals distinctive ε-Si phase morphologies, with Cr addition refining dendritic structures and reducing secondary dendrite arm spacing in the as-cast condition. Cr modification results in smaller-sized grains and a modified ε-Si phase, enhancing nucleation sites and reducing ε-Si size. Microhardness studies demonstrate significant increases in hardness for both alloys after solutionising and aging treatments. Cr-enriched alloy exhibits superior hardness due to solid solution strengthening, and prolonged aging further influences ε-Si particle size and distribution. The concurrent rise in microhardness, attributed to refined dendritic structures and unique ε-Si morphology, underscores the crucial role of Cr modification in tailoring the mechanical properties of aluminium alloys for specific applications.

Characteristics performance evaluation of AZ91-fly ash composite developed by vacuum associated stir processing

ABSTRACT The AZ91 class magnesium alloy was familiar with automotive, aviation, and marine applications due to its uniqueness of being lightweight, high strength, good fracture toughness, better dynamic stability, and good castability behaviours. The novel research aims to enhance the AZ91 alloy composite by adapting fly ash (FA) nanoparticles as 0, 2.5, 5, 7.5, and 10 wt%, respectively, and made by using a vacuum liquid stir casting process under constant stir speed. Influences of FA on micro-structural, physical (density/porosity), mechanical (hardness, impact toughness, tensile stress) and corrosion behaviour of AZ91 alloy nanocomposite were investigated. The composite with 10 wt% FA exposed excellent particle dispersion, better Vickers hardness of 95.4HV, good toughness value of 20.6J/mm2, superior tensile stress of 276MPa, and least corrosion rate of 3.81 mm/year. The optimum characteristics of FANC4 (AZ91/10 wt% FA) are suggested for automotive structural (seat and roof frame) applications.

Theoretical Investigation of Proton Exchange Membrane Fuel Cells Oriented to Automotive Applications

<p>Because of their efficiency and low environmental effect, proton exchange membrane fuel cells, or PEMFCs, are discussed in this abstract as a viable renewable energy source. The paper investigates PEMFCs theoretically, delving into their electrochemical mechanisms and developing a MATLAB simulation model to verify theoretical understanding. Performance parameters such as cell voltage, current density, and power output are assessed in the simulation under various scenarios. The study reveals a number of variables, including temperature, pressure, hydrogen concentration, water quality, and more, that impact PEMFC effectiveness. The best operating conditions for greatest efficiency are found by adjusting these variables and seeing how they affect power production. Furthermore, the study evaluates PEMFC viability for electric cars and comprehends the cell's response to mechanical strain. To sum up, this study uses MATLAB simulations and theoretical analysis to comprehend PEMFC behavior. The results are validated by experiments, which adds credibility to the model. The results support the advancement of PEMFC technology and the creation of sustainable energy sources.</p>

Simulation and Testing of Self-Reconfigurable Battery Advanced Functions for Automotive Application

This article presents the design and production work carried out jointly by Vitesco Technologies and the CEA in order to build a Self-Reconfigurable Battery (SRB) demonstrator representative of an electric vehicle traction battery pack. The literature demonstrates that the use of an SRB allows for individual bypassing or serialization of each cell in a battery pack, enabling control of the voltage output and dynamic balancing of the battery pack during all phases of vehicle use. The simulations and tests presented in this article confirm that the use of an SRB results in a 6% reduction in energy consumption compared to a Conventional Battery Pack (CBP) on a driving profile based on WLTP cycles. Additionally, an SRB enhances fast charging performance, with a charging time that is 22% faster than a CBP. Furthermore, it is shown that an SRB without a voltage inversion capability can still be connected directly to the AC grid for charging without the need for a dedicated converter, using only a single diode bridge rectifier for the whole system.

Multi-objective optimization and comparison of machine learning algorithms for the prediction of tensile properties of aluminum-magnesium alloy

The aluminum-magnesium (Al-Mg) alloy, widely utilized in the aerospace industry is the focal point of this investigation, which examines the effects of temperature, strain rate, and magnesium concentration on its mechanical attributes. These parameters are crucial for their significant roles in both automotive and aviation applications. Through meticulous examination, this study elucidates the influence of these variables on the alloy's tensile strength and stiffness. Employing response surface methodology, it identifies the optimal conditions under which the alloy demonstrates peak mechanical performance. Further, this research conducts a comprehensive comparison of eighteen machine learning algorithms to determine the most effective predictors for these mechanical properties. It highlights Polynomial Regression and Gradient Boosting Tree as the superior models to accurately forecast strength and stiffness, respectively. Not only does this study address the existing gap in the literature regarding the multi-objective optimization and predictive modeling of Al-Mg alloys' tensile properties but also it exemplifies the integration of molecular dynamics simulations with machine learning techniques in materials science research. The insights garnered from this work offer substantial contributions to industrial applications and foster the advancement of computational investigations into Al-Mg alloys.

Joint velocity and angle estimation for single-cycle TDM MIMO automotive radar

Time-division multiplexing (TDM) multiple-input multiple-output (MIMO) radar systems have gained popularity in automotive applications, thanks to their high-resolution and cost-effective properties. However, when the relative motion between the target and the radar is significant and possibly fast time-varying, TDM MIMO systems suffer for reduced maximum unambiguous velocity and angle-Doppler coupling. In this work, a novel off-grid estimation method for TDM MIMO systems is developed that operates on a single cycle and is able to accurately estimate unambiguously the instantaneous velocity and the target direction of arrival (DOA). We model the angle-Doppler coupling through a space-time steering vector. Then, an iterative adaptive approach (IAA)-based method is exploited to reconstruct the 2D velocity-angle spectrum. Additionally, we account for off-grid errors when the targets do not lie on the search grids. A coarse-to-fine strategy is proposed to alleviate the computational burden, where a maximum likelihood (ML) estimator iteratively corrects the off-grid velocity and DOA estimates of each target. Simulated and experimental data are processed to demonstrate the effectiveness of the proposed method.

Efficient Design Methods for Variable-Angle-Tow Composite Toroidal Pressure Vessels

Pressure vessels are widely used in various aerospace and automotive applications. For some applications with limited space, spherical and ellipsoidal shapes are less attractive than toroids. Toroidal shapes can be defined as curved, endless hollow shapes that eliminate the need for end caps when used for pressure vessels. This study presents an analytical formulation using lamination parameters for the novel design of toroidal pressure vessels. The proposed design is based on stiffness tailoring by changing the fiber tow trajectories spatially through the structure to suppress the direct stress and strain gradients in the thickness direction, leading to reduced structural weight, defined as bend-free variable-angle-tow (VAT) toroidal pressure vessels. For a toroidal pressure vessel with a fixed geometry, the VAT distribution through the structure to suppress bending is obtained. Subsequently, the bending stresses and strain levels in the designed VAT toroidal pressure vessels are assessed numerically and compared with those of their isotropic and constant-stiffness composite counterparts. Results show that the designed VAT toroidal pressure vessel generates considerably lower degrees of bending than its corresponding isotropic and constant-stiffness composite counterparts.

81‐2: Automotive OLED Life Extension Utilizing Automatic Luminance Control

Understanding OLED life characteristics is crucial towards implementation of OLED technology into automotive applications. The use of the Arrhenius equation together with the Inverse Power Law may be utilized to estimate the improvement in OLED life when automatic luminance control methods are utilized.

Vehicle Engine Cooling System: Review Research

This study reveals that nano-refrigerants can improve the overall performance of these systems, particularly when used as nanoparticles in conjunction with a base refrigerant. The results show that nano refrigerants outperform base liquids in warm conductivity, and the size of the nanoparticles affects this conductivity. The thickness of nano-refrigerants shows a vertical pattern as the volume of particles increases, while it decreases with temperature increases. Traditional models, such as the Hamilton-Crosser and Einstein models, fail to accurately predict the warm conductivity and consistency of nanoliquids when temperature is considered. Even a small amount of nanoparticles can significantly improve the base liquid’s conductivity. The use of nano-fluids results in an improved convective intensity transfer coefficient for all volume concentrations of nanoparticles compared to water under different working conditions. This study delves into the characterization of nanofluids for vehicle engine cooling systems, focusing on their thermal properties and heat transfer capabilities. Through an analysis of thermal conductivity, heat transfer coefficients, viscosity, and nanoparticle size, the research aims to optimize the design and implementation of nanofluid-based cooling systems to enhance engine performance and fuel efficiency. By investigating the impact of different nanoparticles and concentrations on these properties, the study provides insights into the potential of nanofluids to improve cooling efficiency in automotive applications. The findings highlight the importance of understanding the relationship between nanoparticle characteristics and thermal properties for the effective utilization of nanofluids in vehicle cooling systems. By synthesizing findings from previous studies, this review aims to provide insights into the potential benefits of utilizing nanofluids in enhancing cooling efficiency and overall engine performance in automotive systems. The analysis underscores the importance of considering nanoparticle characteristics in optimizing nanofluid formulations for effective heat transfer in vehicle cooling systems.

Bidirectional DC-DC Converter and Improved Electrical Vehicle Dynamic Response Control

Background: In automotive applications where bidirectional power flow is necessary to lighten the power system, dual active bridge (DAB) converters are frequently employed. Variations in the required output voltage, erratic input voltage, and shifting loads all have an impact on this converter. As a result, converter performance has to be improved. To increase efficiency, the current stress of the DC-DC converter must be optimised. This paper proposes a control scheme for the coupled inductor bidirectional DC-DC (CIB DC-DC) converter utilising both model predictive control (MPC) and a proportional-integral (PI) controller. The integration of these control techniques aims to enhance the performance and efficiency of the converter. Methods: The MPC algorithm is employed to predict the converter's future behaviour based on a dynamic model, taking into account system constraints and performance criteria. By optimising the control action over a finite time horizon, the MPC algorithm ensures an optimal response, considering the current state and anticipated changes. Additionally, a PI controller is incorporated to augment the control strategy. The proportional component of the PI controller enables a fast initial response to the error between the desired and actual converter outputs. The integral component eliminates steady-state errors and provides robustness against disturbances, resulting in improved overall system performance. Results: The proposed control scheme is implemented and evaluated through simulations and experimental tests on a prototype converter. The results demonstrate the effectiveness of the combined MPC and PI controller approach. Conclusion: The coupled inductor bidirectional DC-DC (CIB DC-DC) converter using MPC can provide precise control of power flow between two voltage domains, enabling efficient bidirectional power transfer. The predictive capabilities of MPC allow it to adapt to varying load conditions and respond quickly to changes, ensuring stable operation and accurate regulation of voltage and current. Overall, the coupled inductor bidirectional DC-DC converter controlled using MPC over PI offers improved performance, efficiency, and flexibility compared to traditional control methods. MPC can handle the complex dynamics response and non-linear characteristics of the converter, making it suitable for bi-directional vehicle charging applications, where precise control and high efficiency can be achieved.

94‐3: 60 kHz Ultrasonic Actuators for Animal‐Friendly Haptic Displays

Enhanced piezoelectric coefficient (d33) and mechanical quality factor (Qm) are prerequisite for high performance of resonant piezoelectric applications (e.g., ultrasound haptic displays). We present high performance piezoelectric actuators with a resonant frequency above 60 kHz beyond audible ranges for animals. The ultrasonic actuators provide sufficient tactile feedback with a high vibration displacement, which is superior to that of many state‐of‐the‐art commercial actuators without any visible damages in plastic organic light‐emitting diode (POLED) displays. Furthermore, the actuators can be assembled into an ultrasound loudspeaker, which could facilitate the directional private sound for high‐end automotive applications.

79‐1: Invited Paper: Adaptive Local Backlight Dimming Control with Local Boosting

The local backlight dimming (LBD) technology has attracted significant interest for liquid crystal displays. In automotive, notebook PC, and virtual reality applications, LBD should treat the trade‐off between power saving and visual quality enhancement. However, it requires the cost of the high logic complexity to consider the optimal solution at a higher resolution of the image. This paper proposes the adaptive local backlight dimming control, which can reduce the power consumption of backlight and improve the quality of the display. The proposed method analyzes an image contents with a low complexity algorithm, and it applies a local boosting to achieve a target intensity in backlight control. In performance evaluation using FPGA test system, the designed local dimming processor achieved 7.54% higher power‐saving rate with visual quality enhancement in high‐contrast region.

65‐3: Viewing Angle Control through Electrically‐Induced Effective Out‐of‐Plane Retardation Differences in Automotive Displays

We report a method for controlling the viewing angle using twisted nematic liquid crystal (TN‐LC) materials for automotive display applications. We achieved switching between normal and privacy modes with the change in viewing‐angle‐dependent retardation through the reorientation of the TN‐LC molecules under crossed polarizers by applying a vertical electric field.

Mesh-based topology, shape and sizing optimization of ribbed plates

In this paper, we present a new parameterization and optimization procedure for minimizing the weight of ribbed plates. The primary goal is to reduce embodied CO2 in concrete floors as part of the effort to diminish the carbon footprint of the construction industry. A coupled plate-beam finite element model and its computational mesh enable simultaneous topology, shape and sizing optimization of ribbed plate systems. Using analytical sensitivity analysis and gradient-based optimization, we achieve significant weight reductions in the range of 24–57%, in comparison to reference designs with regular ribbing patterns. The results strengthen the argument in favor of ribbed plates as a structural system that can serve the environmental goals of the construction industry. While our focus is on ribbed concrete plates in buildings, the proposed mesh-based design parameterization is applicable in the general case of optimizing stiffened shells—with potential contributions also to automotive and aerospace applications. All computer codes used in this study are freely available through a public repository, https://zenodo.org/records/11489996.

Studying the effect of polycarbonate sheet integration on glass fiber‐epoxy hybrid composite performance for automotive applications

AbstractThermoplastic polycarbonate provides minimal structural weight and ductility and is a recyclable material. However, investigation of the characteristics of hybrid composites reinforced with woven glass and polycarbonate sheets is limited. This current study investigated the effect of integration of polycarbonate sheets on glass fiber‐epoxy hybrid composite performance. Non hybrid laminate was fabricated from eight layers of woven glass fiber impregnated with epoxy resin (NG). However, the hybrid samples utilized various symmetric stacking patterns which were made by alternating two processed polycarbonate (PC) sheets with six layers of woven glass fiber embedded with epoxy matrix. The manufacturing was made using the hand layup procedure. Mechanical testing includes compressive, tensile, bearing, and hardness was performed on hybrid and non‐hybrid composites. The results showed that employing PC sheets instead of fibers affect the laminate's strength, ductility, bearing capacity, and hardness. Utilization of PC sheets reduces both compressive and tensile strength. However, an enhancement in tensile, compressive, and bearing failure strain was achieved by 2.5%, 31.25% and 31.7%, respectively with hybrid composite having PC in the skin layers as compared with NG. The extent of failure damage is correlated with the position of the PC sheets in the tested samples.Highlights Novel hybrid composites of woven glass fiber and polycarbonate sheet as reinforcement with various stacking orders were successfully prepared by the hand lay‐up method. The compressive strain of hybrid PC samples are higher than NG sample. The hybrid PC composites showed an improved bearing strength and strain performance. The influence of sample configuration on the damage mechanisms has been investigated.

Mechanical and Wear Properties of Developed Cellulosic Fiber-Particles Hybrid Reinforced Epoxy- Based Composites for Automotive Application

Studies are presently ongoing to advance the development of bio-composite materials through the exploration of the potential use of reinforcements of natural origin in polymer matrixes. In this particular investigation, hybrid reinforced composite was formulated for automotive application by utilizing epoxy as the matrix and sisal fiber-paper particles as the reinforcements. The sisal fiber was extracted employing soil retting method, subjected to surface treatment, and combined with paper particles. Following preparation of the reinforcements, predetermined compositions (3, 6, 9, 12 and 15 wt %) were mixed with epoxy resin before being poured into the moulds using hand layup process and were allow to cure. The study focused on the mechanical, wear, and water absorption properties, as well as the surface morphologies of the developed composites. The results of the study revealed that the optimal properties were achieved with the utilization of 9 wt. % and 12 wt. % sisal fiber-paper particles reinforced composite. Particulate paper was discovered to be a suitably surface compatibilizer in thermosets when used as fillers with fiber reinforcement. Thus, the epoxy based composite reinforced with hybrid sisal fiber-paper particles is suitable for automobile application in the fabrication of bumper and other epoxy based body parts.