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Fast charging of traction batteries in passenger cars enables comfortable travel with electric vehicles, even over longer distances, without having to oversize the installed batteries for everyday use. As an enabling technology for fast charging, Kautex presents the implementation of 2-phase immersion cooling, where the traction battery serves as an evaporator in a refrigeration process. The 2-phase immersion cooling enables very high heat transfer rates of 3400 W/m^2*K and at the same time maximizes temperature homogeneity within the battery pack at optimal battery operating temperature. Thus, heat loads at charging rates of more than 6C can be safely and permanently managed by the battery thermal system. The cooling performance of 2-phase immersion cooling can also successfully suppress thermal propagation inside a thermoplastic battery housing.

Concerns about climate change have significantly accelerated the process of vehicle electrification to improve the sustainability of the transportation sector. Increasing the adoption of electrified vehicles is closely tied to the advancement of reliable energy storage systems, with lithium-ion batteries currently standing as the most widely employed technology. One of the key technical challenges for reliability and durability of battery packs is the ability to accurately predict and control the temperature of the cells and temperature gradient between cells inside the pack. For this reason, accurate models are required to predict and control the cell temperature during driving and charging operations. This work presents a set of procedures tailored to characterize and measure the thermal properties in li-ion cells and modules.

The main objective of this paper is to describe the design, analysis and testing of a novel method of insulating the combustion chamber, which is key for efficiency demonstration on a new class of internal combustion engine (ICE). A recuperated split cycle engine (RSCE) has unique demands for heat loss reduction. In particular during the combustion event, to minimize the heat losses is a must to achieve high efficiency. The insulation is provided by a metal plate that is assembled into the cylinder head to line the combustion chamber surface. The design has been focused on reducing heat transfer surface area and exploiting contact gap thermal resistance between the upper surface of the plate and the cylinder head, thus reducing heat wasted to the coolant circuit. In this paper, the plate requirements, functions, design, analysis and test results from a research and development (R&D) program of a heavy duty (HD) recuperated split cycle engine are reported.

Baking ovens in the automotive paint shop are crucial to ensuring quality of paint curing and hence meet the corrosion protection targets in manufacturing process. Ovens are also among the most energy consuming processes in the entire paint shop. With the onset of Electric Vehicle revolution, original equipment manufacturers focus heavily on light weighting resulting in significant design changes to the body in white (BIW). This presents a challenge of achieving accurate curing in the existing ovens designed for the current and past generations of vehicles Using Computational fluid dynamics (CFD), this research intends to present a solution by minimizing the need for prototyping for design changes. Lattice Boltzmann Method (LBM) based thermal simulations are used to predict the curing behaviour on the BIW surface. The LBM based conjugated heat transfer simulations consider turbulence using a Large-Eddy Simulation (LES) approach and Boussinesq approximation.

The China Automotive Technology and Research Center (CATARC) has completed two new wind tunnels at its test centre in Tianjin, China: an aerodynamic/aeroacoustic wind tunnel (AAWT), and a climatic wind tunnel (CWT). The AAWT incorporates design features to provide both a very low fan power requirement and a very low background noise putting it amongst the quietest in the automotive world. These features are also combined with high flow quality, a full boundary layer control system with a 5-belt rolling road, an automated traversing system, and a complete acoustic measurement system including a 3-sided microphone array. The CWT, located in the same building as the AAWT, has a flexible nozzle to deliver 250 km/h with an 8.25 m2 nozzle, and 130 km/h with a 13.2 m2 nozzle. The temperature range of the CWT is -40 °C to +60 °C with a controlled humidity range of 5% to 95%. Additional integrated systems include a variable angle solar simulator array, and a rain and snow spray system.

The discussed invention is centered on the evaporative cooling of a vehicle cabin, introducing a novel concept of humidity control. Unlike conventional Air Conditioning (AC) systems that operate on the Vapor Compression Refrigeration Cycle (VCRC), which tend to be costly and contribute to higher fuel consumption due to the engine-driven compressor in automobiles, there is currently no other Original Equipment Manufacturer (OEM) fitted cabin cooling option available to address this issue. This paper introduces the idea of a humidity-controlled evaporative cooler. The objective of humidity control is achieved through a controller unit that receives feedback from a humidity sensor, subsequently regulating the operation of the water pump. The ambient air is passed through a humidified honeycomb pad, cooling through the principle of evaporation. To prevent any leftover water droplets from entering the cabin, a polyester nonwoven filter has been integrated into the system.

Turbulent jet ignition (TJI) combustion using pre-chamber ignition can accelerate the combustion speed in the cylinder and has garnered growing interest in recent years. However, it is complicated for the optimization of the pre-chamber structure and combustion system. This study investigated the effects of the pre-chamber structure and the intake ports on the combustion characteristics of a gasoline engine through CFD simulation. Spark ignition (SI) combustion simulation was also conducted for comparison. The results showed that the design of the pre-chamber that causes the jet flame colliding with walls severely worsen the combustion, increasing the knocking intendency, and decrease the thermal efficiency. Compared with SI combustion mode, the TJI combustion mode has the higher heat transfer loss and lower unburned loss. The well-optimized pre-chamber can accelerate the flame propagation with knock suppression.

A need to develop a cooling method with high cooling performance like jet impingement is increased as high power of an inverter is required. Jet Impingement on the dimpled plate would increase thermal performance than that of flat plate. Many previous researchers have dealt with the multi jet impingement on flat plate and some results of the study on dimpled plate evaluate the effect on heat transfer coefficients on several limited cases, making it difficult to apply them to inverter designs. Therefore, in this paper, heat transfer performance, pressure drop, and robustness at micro-scale of jet impingement on the dimpled plate were investigated in detail and the correlations of each performance were proposed. Finally, the optimal design was presented. The cooling performance was influenced by the jet array and the effect of depth and width of the dimples.

Per - and polyfluoroalkyl substances – known as PFAS are man-made chemicals that do not occur naturally. PFAS are widely used, long lasting chemicals, components of which break down very slowly over time. Scientific studies have shown that exposure to some PFAS in the environment may be linked to harmful health effects in humans and animals. Because of their widespread use and their persistence in the environment, many PFAS are found in human and animals’ blood all over the world and are present at low levels in a variety of food products and in the environment. PFAS are found in water, air, fish, and soil at locations across the nation and the globe. Both refrigerants (HFC-134a & HFO-1234yf) that are currently used in mobile air conditioning systems (MACS) create PFAS. Hence, various countries are looking into banning chemicals that create PFAS. Natural refrigerants are being proposed as alternative refrigerants as they do not create PFAS.

The study of temperature distribution and heat transfer over non-uniform geometry is of great importance to engineers because of universal occurrence in many engineering applications such as diesel engine, boilers, heaters, radiators, dosers, etc. Performance of engine and its components (mechanical and electronic) is highly depending upon efficient thermal management. An accurate heat transfer analysis is necessary in automotive application and power plant. This study presents one dimensional model for prediction of conjugate heat transfer in Aftertreatment system and Sensors Module (Nox Sensor, PM Sensor, EGTS etc..) for diesel engine. Three-dimensional conductive, convective and radiative thermal analysis is computationally expensive as underhood models are of complex shape in nature and total turnaround time for product development project is also significantly high.

Internal combustion engine (IC engine) vehicles are commonly used for transportation due to their versatility. Due to this, efficiency in design process of IC engines is critical for the industry. To assess performance capabilities of an IC engine, thermal predictions are of utmost consequence. This study describes a computational method based on unsteady Reynolds-averaged Navier–Stokes equations that resolves the gas–liquid interface to examine the unsteady single phase/multiphase flow and heat transfer in a 4-cylinder Inline (i-4) engine. The study considers all important parts of the engine i.e., pistons, cylinder liners, head, block etc. The study highlights the ease of capturing complex and intricate flow paths with a robust mesh generation tool in combination with a robust high-fidelity interface capturing VOF (Volume-of-Fluid) scheme to resolve the gas-liquid interfaces.

An escalating demand for improved heat dissipation from electronic components is driven by the imperative need to eliminate the accumulated heat that gradually builds up over time. In this study, a 3-D simulation was carried out to analyze the heat distribution performance of a heat sink based on PCM/NePCM. The heat sink was subjected to varying heat fluxes ranging from 3-7 kW/m2, and its performance was evaluated over time. The findings of the computational research indicate that using PCM assists in maintaining the heat sink base's temperature within lower bounds, and leads to uniform melting within the heat sink. Further, inclusion of Alumina nano particles integration in PCM enhanced the performance of heat sink. The percentage reduction in charging time of NePCM without fins (φ = 1%, 2.5% and 5%) in comparison to the Pure-PCM (φ = 0%) is 6%, 11% and 51% respectively at 6 kW/m2 input.

Friction stir welding (FSW) is a method of welding that creates a weld trail by pressing a non-consumable rotating tool with a profiled pin on the adjacent surfaces while moving transversely along the welding direction. The method was initially used with metals and alloys, but more recently, thermoplastic polymers have also been included in its application. Investigations on FSW of thermoplastic polymers made of nylon and High-density polythene (HDPE) are presented here. Weld characteristics that are like those of the base materials are attempted to be achieved. Because of their unique nature and thermal conductivity, thermoplastics FSW differs from that of metals. The use of thermoplastic materials with conventional FSW procedures presents numerous difficulties and is currently ineffective. On the weld characteristics of nylon and HDPE, statistical methods were utilized to study the impact of temperature, rotational speed, and transverse speed.

Geometry simplification is a critical step of performing conjugate heat transfer analysis utilizing computational fluid dynamics (CFD). This paper provides a standard methodology to simplify the geometry of electric rotating machines such as electrical generators and electrical motors (both air and liquid cooled). These machines are extremely complex in design and CFD plays an imperative role in their optimization. These machines are extensively deployed throughout aerospace and automotive industries where optimization of weight, volume, and performance is paramount especially given the current global transition to renewable energy sources and vehicle hybridization / electrification.

Composites of polymers reinforced with synthetic/natural fibers are mainly used in engineering sectors such as automobiles, aerospace, and in household appliances due to their abrasion resistance, high toughness, strength, and high specific modulus. The purpose of this research is to provide an overview of fiber-matrix interfaces and interface mechanism that leads to enhanced properties. This article investigates how natural/synthetic fibers, mineral based-materials and additional allotropic materials work rapidly and effectively across interfaces.

The latest developments in composite materials are anticipated by green engineering. Materials must be eco-friendly, recyclable, biodegradable, and easy to decompose. Researchers are interested in utilizing natural fibres, fillers, and synthetic active ingredients. Natural fiber-polymer composites can specify certain mechanical properties but are hydrophilic and weak, so they rarely meet the needed thermal properties. Composite material selection depends on the application and the superior properties of the fibre/filler: banana fibre (BF), ice husk (RH) and multi-walled carbon nanotubes (MWCNT). In this research article, a brief discussion of the heat transfer mechanism of composites and the development of energy conduction equation are performed for hybrid natural polymer composite. The maximum thermal conductivity observed for 10BF/10RH/1MWCNT wt.% composite is 0.2694 W/mK.

With the evolving demand in the automobile industry for lightweight and sustainable components, the study of natural fiber composites has gained significance. Such fibers are economically efficient and offer advantageous weight-specific properties. Additionally, they are non-abrasive and environmentally degradable, marking them as viable alternatives to conventional automobile materials. This research emphasizes the flax-based composite, developed using the hand lay-up method and augmented with three distinct graphene nanofillers. The graphene fillers are categorized as large nanorods (dimensions 3-5 nm, lengths 150-300 nm), small nano threads (dimensions 6-12 nm, lengths under 50 nm), and spherical particulates (dimensions 29-39 nm). Reinforcement was consistently maintained at 2%, 4%, and 6% by weight.

This test method specifies the operating procedures for a controlled-irradiance, xenon-arc apparatus used for the accelerated exposure of various automotive interior trim components. Test duration, as well as any exceptions to the specimen preparation and performance evaluation procedures contained in this document, are covered in material specifications of the different automotive manufacturers. Any deviation to this test method, such as the use of optical filter combinations, is to be agreed upon by contractual parties.

Vehicle electrification is game changer for automotive sector because of major energy and environmental implications driven by high vehicle efficiency. However, EVs are facing challenges on life cycle assessment (LCA), charging, and driving range compared to conventional fossil-fueled vehicles. One of the key features that impacts the efficiency of an EV is its battery charging system which is done using an On-Board Charger (OBC). OBCs, are primarily used to convert DC-power from high-voltage battery pack to AC-power. They contain different power-electronic devices such as MOSFETs, diodes, magnetics etc. These devices generate a lot of heat and require an efficient thermal management strategy. Through CAE Thermal analysis it was identified that amongst these components, transformers and diodes are major source of heat. Temperature observed at these component locations were in the range of 90-105 °C, compared to other components (45-75°C).

Roots blower is a rotary positive displacement pump which operates by pumping a fluid with a pair of meshing lobes. Recent trends in automotive industry demands high power density solutions for various applications. In comparison with legacy applications, compressors for high power density applications demand continuous operation with harsher duty cycle as well as demand higher pressure ratios. Because of longer duty cycles, it will be subjected to high heat loads which will cause a rise in temperatures of timing gears, bearings, and other components within the assembly. Accurate prediction of thermal performance is critical to design a durable and efficient roots blower for high power density applications. Thermal analysis of an assembly of roots blower involves modelling of multi-physics phenomena. This paper details a coupled CFD analysis approach to predict temperatures of roots blower components and timing gear case oil. Timing gears are lubricated using wet sump lubrication.