Automotive Science and Engineering

Geometric Patterns Liquid Cooling System for Lithium-Ion Batteries in Electric Vehicles Considering Driving Cycle

Ayat Gharehghani

A novel liquid cooling system for pouch-type lithium-ion batteries (LIBs) is proposed by focousing on uniform temperatue disturbution and effective heat dissipation. The system utilizes a michrochannel cold plate with an innovative coolant disturbution design. This study proposes a novel microchannel disturbution path design with each microchannel dimensioning 1 mm² and embeded in the battery's ciritical region to enhance the thermal contact among the LIB and the microchannels. This study aims to simulate and evaluate the performance of cooling system under varius Iranian environmental conditions (Tehran, Shiraz, Isfahan, and Bandar Abbas) and operational parametrs (channel pattern, flow rate) to achieve optimal battery temperature and reduce energy consumption.

Torsional and bending stiffness and modal analysis of a bus structure

Zahra Taghizade

A bus experiences various loads during operation, stressing its structural components and causing noise, vibrations, and strains. To withstand these stresses, components must have sufficient stiffness, strength, and fatigue properties. In this study, the CAD model of a bus was created in SolidWorks and meshed using HyperMesh. A modal analysis conducted in HyperMesh verified the model's integrity, welding joint accuracy, and suitability for further analysis. A HyperMesh solver performed bending and torsional analyses. The torsional and bending stiffness of the bus body was calculated based on these results. Previous research primarily focused on stress and displacement, neglecting torsional and bending stiffness analysis for three-axle buses. This study addresses this gap, providing industry engineers with insights into acceptable torsional and bending stiffness for intercity buses. This knowledge supports the design of buses with adequate braking and turning capabilities. Additionally, the research contributes to bus body optimization efforts. In subsequent studies, scientists can experiment with various materials and models of various bus structure beam profiles.

A comprehensive study on air transverse flow effects on the collision behavior of a supercooled water droplet

mahdi moghimi

The impact of a supercooled droplet on a surface is a primary challenge of many industrial and aeronautical processes. However, in some cases, such as frost formation on vehicle windshields or wind turbine blades, the supercooled droplet collision does not occur in stagnant air. In this study, for the first time, the effects of the air transverse flow (ATF) on the thermal-fluid behavior of a supercooled droplet were investigated numerically. Also, different patterns of a superhydrophobic pillared surface were used in 24 three-dimensional simulations in ANSYS Fluent software. The volume of fluid method is chosen for the simulation of the multiphase flow. The freezing model is improved by the supercooling temperature consideration method. The results show that the ATF velocity reduces the separation time exponentially and helps the droplet bounce from the surface before freezing inception. However, the excessive increase in ATF velocity has the opposite effect and may prevent the droplet from detaching the surface due to notable drag. The best value of the ATF velocity is obtained to be 8 m/s , which reduces the separation time exponentially from 16.3 ms to 12.5 ms for a cold surface with a simple pillar pattern. The separation time is entirely affected by the simulation conditions and varies from 11.85 ms to 29.2 ms . The maximum spreading factor, despite the separation time, is seriously influenced by the void fraction percentage of different pillared surfaces and varies from 1.53 to 1.69.

Effects of adhesive layer thickness and adhesive fillet on creep behavior of automotive bonded joints subjected to sustained tensile loads

Hamed Saeidi Googarchin

Adhesively bonded joints are a highly effective method for achieving lightweight structural designs, yet assessing their long-term durability remains a significant challenge. Creep, a time-dependent effect caused by sustained mechanical loads, can result in viscous strain within adhesive materials, potentially leading to crack formation in bonded structures over extended periods. This study investigates the creep behavior of adhesive joints under sustained tensile loads, focusing on the effects of adhesive layer thickness and the presence of adhesive fillets. Creep tests conducted over 48 hours revealed that higher load levels result in greater strain accumulation, with thicker adhesive layers showing increased susceptibility to deformation. Additionally, joints with adhesive fillets demonstrated lower creep strain, indicating enhanced resistance to sustained loads. These findings emphasize the importance of adhesive layer thickness and fillet design in optimizing the long-term performance and durability of bonded joints, offering valuable insights for applications where creep resistance is critical for joint reliability and service life.

Role of Nozzle Hole Diameter in Modulating Spray Dynamics and Enhancing Combustion Performance in Reactivity-Controlled Compression Ignition Engines

Mehran Nazemian

This study investigates the influence of nozzle hole diameter (NHD) variations on spray dynamics, combustion efficiency, and emissions in a Reactivity-Controlled Compression Ignition (RCCI) engine using Computational Fluid Dynamics (CFD) simulations with the CONVERGE software. The study systematically examines NHDs ranging from 130 µm to 175 µm and evaluates their impact on key parameters such as injection pressure, droplet formation, Sauter Mean Diameter (SMD), and evaporation rates. The results demonstrate that reducing NHD to 130 µm significantly enhances fuel atomization by reducing SMD to 15.49 µm and increasing droplet number by 24%, which in turn accelerates evaporation and improves fuel-air mixing. These effects shorten ignition delays, accelerate combustion, and increase peak cylinder pressures and temperatures. Optimal NHDs (150–160 µm) achieve the highest combustion efficiency (92.04%) and gross indicated efficiency (38.58%). However, further reduction in NHD below this range causes premature ignition, energy dissipation, and higher NOx emissions (10.08 g/kWh) due to elevated combustion temperatures. Conversely, when the NHD increases to 175 µm, the larger droplets formed result in prolonged ignition delays, slower combustion, and lower peak pressures. These effects negatively impact combustion efficiency and promote incomplete combustion, leading to higher HC (15.27 gr/kWh) and CO (4.22 gr/kWh) emissions. Larger NHDs, however, lower NOx emissions to 2.66 gr/kWh due to reduced peak temperatures. This study clearly identifies an optimal NHD range (150–160 µm) that effectively balances droplet size, evaporation rate, combustion timing, and emission reduction, thereby enhancing both engine performance and environmental sustainability.

Unlocking the Recycling Strategies: A Review on challenges, Potential, and approaches

Farshad Boorboor Ajdari

Today, the utilization of lithium-ion batteries (LIBs) has significantly increased as an energy storage technology. In recent years, the high demand for lithium for LIB has resulted in a significant increase in the consumption of lithium-containing materials. It is anticipated that the reduction of lithium due to the limited reserves of lithium will be one of the major challenges in the future. The primary component of the lithium-ion battery industry is lithium, which is extracted from natural minerals and saline water. However, the extraction of lithium from natural minerals and saline water is a complex process that requires a significant amount of energy. Conversely, the quantity of batteries that are approaching the end of their lifespan is unavoidably increasing at an alarming rate. In order to address the obstacles that the lithium battery supply chain encounters, it is imperative that a variety of recycling technologies and methodologies be further developed. This article concentrates on technologies that can recycle lithium compounds from LIB through distinct processes and procedures. These stages are further divided into two pre-treatment phases and a lithium extraction stage. The lithium extraction stage is further divided into three primary methods: pyrometallurgy, hydrometallurgy, Direct. This review article quantitatively compares and analyzes the processes, advantages, disadvantages, efficiency, price, environmental contamination, and degree of commercialization of each recycling method. This review can offer a suitable perspective to enhance this path.