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Training / Education

Introduction to Commercial and Off-Road Vehicle Cooling Airflow Systems

2024-09-12
Vehicle functional requirements, emission regulations, and thermal limits all have a direct impact on the design of a powertrain cooling airflow system. Given the expected increase in emission-related heat rejection, suppliers and vehicle manufacturers must work together as partners in the design, selection, and packaging of cooling system components. The goal of this two-day course is to introduce engineers and managers to the basic principles of cooling airflow systems for commercial and off-road vehicles.
Technical Paper

Niobium Alloyed Ferritic Nitrocarburized Brake Rotors

2024-09-08
2024-01-3031
Brake rotor wear durability and resistance to dust generation are under increasing demands to meet proposed environmental requirements. Improved rotor output, or the ability to turn kinetic energy into heat are driving more aggressive friction materials that increase wear of the brake rotor. Regenerative braking systems have unique challenges in corrosion cleanability that require aggressive friction materials in combination with good corrosion performance. Grey cast iron remains the material of choice for brake rotors due to the advantages of near net shape capability, good thermal conductivity, and low cost. Niobium (Nb) alloyed Grey cast iron in combination with Ferritic Nitrocarburize (FNC) case hardening heat treatment is proposed to improve wear resistance and reduce brake dust generation of brake rotors. Niobium additions in cast iron were shown in prior investigations to reduce the eutectic cell size and refine the pearlite matrix.
Technical Paper

A Study on the countermeasure to EURO7 Brake Dust Regulation Phase 1

2024-09-08
2024-01-3049
In order to cope with the brake dust regulation of EURO7, countermeasures were listed, and evaluation and verification studies were conducted on them. Through this phase1 study, it was most reasonable to apply hard metal cladding disks to front brake and apply friction materials as NAO with less dust generation to rear brake. This is because it is possible to Satisfy new regulations without deteriorating the required performance in Europe. However, it is necessary to develop detailed specifications of discs and friction materials to satisfy our braking development goals in the Phase 2 to optimize performance target for European models.
Technical Paper

Glow-discharge Optical Emission Spectroscopy Study of Cr(III) Sealing in Anodized Aluminium-Silicon Alloys for Brake Component

2024-09-08
2024-01-3038
Calipers and pistons for high-end car braking systems are typically realized using anodized Aluminium-Silicon alloys. Indeed, Aluminium-Silicon alloys are light materials with optimal mechanical properties and, when anodized, excellent corrosion and wear resistances. To achieve these top-notch surface properties, the anodizing process is followed by a sealing post-treatment, which significantly improves the corrosion resistance and tunes the tribological properties (e.g., hardness and friction coefficient) of the anodized pieces. Sealing consists in the precipitation of insoluble hydroxides and functional compounds (e.g., corrosion inhibitors) inside the nano-pores of the anodic layer. Nevertheless, sealing might not penetrate through all the nano-porous structure of the anodic layer. Thus, in light of possible post-machining of sealed, anodized components, it appears fundamental to develop a tool to determine the depth penetration of sealing inside the anodic layer.
Technical Paper

Initial Corrosion and Wear Behavior of Brake Rotors Treated with Plasma Electrolytic Aluminating or Ferritic Nitrocarburizing Process

2024-09-08
2024-01-3043
To combat corrosion and wear issue of automotive brake discs, many manufacturers have introduced various surface treatment technologies, such as thermal spraying, laser cladding, and ferritic nitrocarburizing (FNC). Besides those surface treatment technologies, a plasma electrolytic aluminating (PEA) process has also shown to be effective in producing alumina-based ceramic coatings on cast iron substrates, providing an enhanced corrosion resistance. In this study, the PEA-coated brake rotor and FNC-treated brake rotor were comparatively tested in various corrosion conditions, including an electrochemical corrosion test and simulative corrosion experiment, before and after a road driving test. A scanning electron microscope (SEM) and an energy-dispersive X-ray (EDX) were used to observe and analyze morphology and chemical compositions of the surfaces and cross-sections of the tested rotors.
Technical Paper

Reduction of Flow-induced Noise in Refrigeration Cycles

2024-07-02
2024-01-2972
In electrified vehicles, auxiliary units can be a dominant source of noise, one of which is the refrigerant scroll compressor. Compared to vehicles with combustion engines, e-vehicles require larger refrigerant compressors, as in addition to the interior, also the battery and the electric motors have to be cooled. Currently, scroll compressors are widely used in the automotive industry, which generate one pressure pulse per revolution due to their discontinuous compression principle. This results in speed-dependent pressure fluctuations as well as higher-harmonic pulsations that arise from reflections. These fluctuations spread through the refrigeration cycle and cause the vibration excitation of refrigerant lines and heat exchangers. The sound transmission path in the air conditioning heat exchanger integrated in the dashboard is particularly critical. Various silencer configurations can be used to dampen these pulsations.
Technical Paper

Next-gen battery strategies 2027+: Potentials and challenges for future battery designs and diversification in product portfolios to serve a large bandwidth of market applications

2024-07-02
2024-01-3018
The pace of innovations in battery development is revolutionizing the landscape and opportunities for energy storage applications leading to a stronger market segmentation enabling a better suitability to fulfill specific application requirements. For automotive applications, several approaches to increase energy densities, to improve fast charging performance, and to reduce cost on a pack level are considered. Among them, a promising example is the direct integration of battery cells into the battery pack (Cell-to-pack; CTP) or vehicle (Cell-to-chassis, CTC) to increase energy densities and to reduce costs, as already commercialized by Tesla, CATL and others. In the pack development, especially Asian players are one of the frontrunners, where e.g., hybrid cell battery systems with a mixture of cells with different cathode chemistries as introduced by NIO, are experiencing a high interest of the market.
Technical Paper

Current and Torque Harmonics Analysis of Triple Three-Phase Permanent-Magnet Synchronous Machines with Arbitrary Phase Shift Based on Model-in-the-Loop

2024-07-02
2024-01-3025
Multiple three-phase machines have become popular in recent due to their reliability, especially in the ship and airplane propulsions. These systems benefit greatly from the robustness and efficiency provided by such machines. However, a notable challenge presented by these machines is the growth of harmonics with an increase in the number of phases, affecting control precision and inducing torque oscillations. The phase shift angles between winding sets are one of the most important causes of harmonics in the stator currents and machine torque. Traditional approaches in the study of triple-three-phase or nine-phase machines mostly focus on specific phase shift, lacking a comprehensive analysis across a range of phase shifts. This paper discusses the current and torque harmonics of triple-three-phase permanent magnet synchronous machines (PMSM) with different phase shifts. It aims to analyze and compare the impacts of different phase shifts on harmonic levels.
Technical Paper

An Approach to Design an Air–Liquid Supersonic Ejector for Producing Aerosol Spray

2024-06-25
2024-01-5068
This study aims to design a supersonic ejector, referred to as a liquid spray gun, with a simple operating procedure for producing an aerosol spray with adjustable droplet size distributions. A CFD model was developed to determine the influence of nozzle exit position and the primary air pressure on the supersonic patterns formed within the ejectors, providing a valuable insight into their internal physics. Based on the single-phase numerical results, at an air primary pressure of 2 bar, the flow may not reach a choking condition, possibly resulting in unstable ejector operation. However, at pressures exceeding 5 bar, the jet patterns emerging from the primary nozzle cause flow separation or the formation of vortex rings. This phenomenon leads to a flow configuration comparable to the diameter of the mixing tube, thereby reducing the available area for entrainment of suction flow.
Technical Paper

Optimization of Hydroformed Exhaust Gas Recirculation Tube under Vibrational Load by Finite Element Analysis

2024-06-17
2024-01-5062
This study emphasizes the importance of CAE approach in optimizing EGR tube under vibrational load. EGR tube is a weak link in the EGR system and chances of failure due to vibration and relative displacement of mating parts, i.e., overhang or improper support at exhaust manifold, intake manifold, or EGR system. Consideration of the mating parts for the EGR tube is very important to get the realistic resonance frequencies, otherwise it could have some different results in the CAE, which will deviate from the reality. So, it’s important to study the dynamic response on the EGR tube, which needs to be taken care during the design phase. This paper aims to optimize the EGR tube under vibrational load by using CAE techniques and the industry experience as a product expertise. some critical parameter such as damping is very important during the CAE, which can be generated by doing the rigorous testing and how it affects the stress and correspondingly FOS.
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