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During the development phase of any Powertrain component/subsystem for a conventional ICE or an XEV (Hybrid/Battery Electric Vehicle), system Energy efficiency and Performance improvement simulations are a very important step to prove the worthiness of the product before we can advance to building Prototypes, Vehicle level Integration, Testing, analysis and benefit’s evaluation phases. This work describes how two simulation tools have been leveraged effectively for Energy efficiency and Performance simulations for an Electric vehicle. Schaeffler has an internal Physical Modelling Tool (PMT) for building vehicle level models. This tool has readymade physical blocks for various Mechanical and Electrical components. These blocks can be parameterized as per required specifications. The powertrain subsystems like the Battery, BLDC Motor, Vehicle Dynamics and the Multi-speed transmission consisting of various mechanical elements have been modelled and parametrized using this tool.

This paper summarizes the Fast Fourier Transform (FFT) methodology, special equipment, set-up and testing that is recommended to properly characterize the surface of bearing journals that will not result in objectionable noise or vibration. Traditional surface profiles and finish callouts do not capture some of the key characteristics for addressing what is often the customer's greatest complaint, noise. Noise can vary based on the sensitivity of the vehicle but understanding how to accurately describe (design, test, and measure) a surface for a given vehicle can result in an optimized design and reduce process time during manufacturing. Furthermore, this paper will recommend techniques for determining the proper limits of the FFT callouts.

An ignition delay correlation was developed for a toluene reference fuel (TRF) blend that is representative of automotive gasoline fuels exhibiting two-stage ignition. Ignition delay times for the autoignition of a TRF 91 blend with an antiknock index of 91 were predicted through extensive chemical kinetic modeling in CHEMKIN for a constant volume reactor. The development of the correlation involved determining nonlinear least squares curve fits for these ignition delay predictions corresponding to different inlet pressures and temperatures, a number of fuel-air equivalence ratios, and a range of exhaust gas recirculation (EGR) rates. In addition to NO control, EGR is increasingly being utilized for managing combustion phasing in spark ignition (SI) engines to mitigate knock. Therefore, along with other operating parameters, the effects of EGR on autoignition have been incorporated in the correlation to address the need for predicting ignition delay in SI engines operating with EGR.

The double linear damage model developed by Manson and Halford helps to determine the knee point, which is the intersection between the two straight lines. The damage to the component is then calculated based on this knee point. The new approach mentioned in this paper helps to evaluate the damage on the component in a slightly different way. It uses the knee points as mentioned by Manson and Halford and decomposes the damage to the component for Phase I & Phase II. It then uses the equivalent damage approach and establishes the damage to the component. This will be explained with an example.

Advanced High-Strength Steels (AHSS) have become an essential part of the lightweighting strategy for automotive body structures. The ability to fully realize the benefits of AHSS depends upon the ability to aggressively form, trim, and pierce these steels into challenging parts. Tooling wear has been a roadblock to stamping these materials. Traditional die materials and designs have shown significant problems with accelerated wear, galling and die pickup, and premature wear and breakage of pierce punches. [1] This paper identifies and discusses the tribological factors that contribute to the successful stamping of AHSS. This includes minimizing tool wear and galling/die pick-up; identifying the most effective pierce clearance (wear vs. burr height) when piercing AHSS; and determining optimal die material and coating performance for tooling stamping AHSS.

Scuffing is one of the major problems that influence the life cycle and reliability of several auto components, including engine cylinder kits, flywheels, camshafts, crankshafts, and gears. Ferrous casting materials, such as gray cast iron, ductile cast iron and austempered ductile cast iron (ADI) are widely applied in these components due to their self-lubricating characteristics. The purpose of this research is to determine the scuffing behavior of these three types of cast iron materials and compare them with 1050 steel. Rotational ball-on-disc tests were conducted with white mineral oil as the lubricant under variable sliding speeds and loads. The results indicate that the scuffing initiation is due to either crack propagation or plastic deformation. It is found that ADI exhibits the highest scuffing resistance among these materials.

Contact rubber seals have been extensively employed in bearing systems in order to avoid internal dusty contamination and grease leakage. As an inherent consequence, heat and friction losses arises from the sliding contact of these seals. Indeed, the increasing speed of mechanisms, warranted by the desire for increase power, leads to higher operating temperatures and reduced fluid viscosities, associated with higher pressures, what cause an increasing tendency for fluids to leak. Such characteristics require the design of high performance sealing systems to avoid grease leakage and bearing contamination, but at low rates of friction and heat generation. [1] By means of Finite Element Analysis and Experimental Procedures such as DoE, this study aims to isolate and evaluate the influence of the seal design and its several parameters on the friction variables such as resistance torque.

The water and dust contamination has being studied as an important factor for the components life. For the evaluation of water and dust, it is important that a good method of analysis has been defined. This paper will present a method used to evaluate the grease contamination with dust and water and the actions made to improve the analysis of grease. In order to evaluate the water content in the grease, it was used the Karl Fischer titration. This method determines trace amount of water in a sample. A restriction of this analysis is the grease sample amount, which could not be fully titrated. So just part of the grease (contaminated with water) is analyzed and due to the heterogeneity of the grease and water mixture, this small sample of grease does not necessarily have the same amount of water than the whole grease.

The basic function of the clutch, transmitting torque when running, interrupting the flow of power between the engine and gearbox in the changing gears and stopping and protecting the engine and transmission against overload and dampen vibration transmission. The plateau clutch with spring membrane is the system used today. The modern clutches are small and save space in the engine compartment reducing the total weight of transmission, minimizing the resistance to rotation of the motor, providing less mechanical losses. The construction and assembly of the membrane spring clutch assembly is very important, since misalignment of reeds could result in chatter or vibration in clutch pedal, along with the hard drive of the pedal, which can also generate a deformation of the components and thus premature wear of the clutch.

The development process of a water pump impeller used on a sport utility vehicle engine is described. A review of the design process is presented in this paper including the computer-aided flow analysis together with testing procedures. By computer modeling, one can estimate the coolant flow characteristics of a given impeller blade shape for providing increased cooling performance and improved efficiency on the engine. It also provides directions for the improved design. The test data are used specifically to confirm the analysis results.

In an effort to improve the dent resistance of exterior body panels at reduced steel thicknesses, some automobile manufacturers have pursued the application of bake hardenable steels. Unfortunately, bake hardenable steels have only been available as cold rolled or with electro-zinc or electro zinc/iron coatings. This situation has been a deterrent for those automobile manufacturers that prefer the use of hot dip galvanneal coatings. Recently, the interest in hot dip galvanneal bake hardenable steels has led to the investigation and development of this more advanced steel grade. This paper presents the results of a stamping trial and dent testing on three exposed hot dip galvannealed materials; i) Regular Ultra Low Carbon (ULC), ii) Rephosphorized ULC, and iii) Rephosphorized Bake Hardenable ULC steel.

The accuracy of the simulation of NVH behavior is strongly dependent on parameters such as stiffness and damping of the structure as they have a direct influence on the results. This paper is focused on a straightforward method of achieving and implementing acceptably accurate damping values in joints in the early development phase. With emphasis on ease of use and independent software, a Kelvin-Voigt model is used to generate damping behavior. Based on a modal test, damping parameters are achieved and the base model is calibrated. Using this as a starting point, damping parameters and topographical values are optimized with the focus being on minimizing the simulated radiated acoustic power. The method is represented on a simplified disc structure and results are discussed.

Today, some vehicles include a regenerative-braking system such as the electrical motor-generator that converts the vehicle's kinetic energy into electrical energy to recharge one or more vehicle batteries. The idea is to use air flow to produce additional electrical energy in response to deceleration of the vehicle. With the Wind Power Generator System (WPGS) as a green system, a vehicle can produce extra energy, reduce gasoline usage, and reduce air pollution.

Indian Two-wheeler market is the biggest in the world. In two-wheeler segment, scooters have seen a growth of about 27% year-on-year in 2015 and the trend continues in 2016. This healthy growth is due to their ease of handling and operation. This can be majorly attributed to the use of a Continuously Variable Transmission (CVT). While the CVT does offer considerable comfort to rider due to an absence of manual gear-shifting and clutch operation, it also suffers from the drawback of dragging the engine during deceleration phases, which adversely affects fuel efficiency of scooters with carburetor engine, which are quite common in India. Average Fuel efficiency of scooters is ~ 25% less compared to motor bikes with same engine configuration. Also, vibrations due to the engine drag are noticeable.

Improving vehicle performance in terms of both torque and power is a strong customer need in both conventional and electric vehicles. In this work, different two speed automatic transmission (AT) concepts are developed to improve the energy efficiency and performance of battery electric two wheelers. Developed transmission systems are simple, compact and cost effective and results in relatively high energy efficiency of an electric motor. The unique shift control strategy ensures motor to operate at higher efficiency zones to minimize the overall energy consumption. Virtual simulations of electric vehicle were carried out for different driving conditions and optimal transmission ratios were determined. Mechanical behaviors such as gear shift characteristics, linear and angular velocities, inertial forces of each components are analyzed by using Multi body dynamics simulation. Forces predicted here are further used for durability studies of these components.

Manual transmissions play a dominant role in India with a market share of more than 90%. Any technology that improves their fuel consumption and their comfort for end users is highly welcome if it is affordable regarding “value for money”. Schaeffler offers a technology to meet these challenges with the concept of Electronic Clutch Management (ECM). By implementing an intelligent mechatronic clutch actuator with specific, integrated sensors directly inside the actuator, this development prepares the ground for a new era that says farewell to the clutch pedal and achieves the target of using a 2-pedal system.