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Training / Education

Engineering Project Management

2022-06-21
Project Management and Advanced Product Quality Planning (APQP) are two critical techniques used in product development in the mobility industry today. This seminar will bring these techniques together in an easy to understand format that goes beyond the typical concept of constructing timelines and project planning, by exploring not only the Automotive APQP process, but also key aspects of PM processes. Students will gain a solid foundation in the principles and application of Project Management and APQP.  
Technical Paper

A general framework for the experimental characterization of nonlinearities and its application to a laminated assembly of an electrical motor

2022-06-15
2022-01-0944
As the vehicle industry is in the middle of transformation, the development of electric drives came into focus of engineers. The parameter evaluation of dynamic systems can be cumbersome when having nonlinearity in the structure, for example nonlinear stiffness characteristics. In such case, the standard linear approach, including EMA (Experimental Modal Analysis), modal superposition, FRF measurement (Frequency Response Function) and modal synthesis can not be applied. However, one of the main challenges in addressing nonlinearities is the lack of general tools to approach them. In this paper, a general framework is presented aiming the examination of nonlinearities in a structural dynamic context. The method relies on standard random and sine sweep testing approaches to detect and localize nonlinearities, and on dedicated processing techniques to analyze the data and extract information on the nature of the analyzed nonlinearity.
Technical Paper

Effects of Boundary Layer and Local Volumetric Cells Refinements on Compressor Direct Noise Computation

2022-06-15
2022-01-0934
The use of turbochargers with downsized internal combustion engines improves road vehicles’ energy efficiency but introduces additional sound sources of strong acoustic annoyance on the turbocharger’s compressor side. In the present study, direct noise computation (DNC) is carried out on a passenger vehicle turbocharger compressor. The work focuses on assessing the influence of grid parameters on the acoustic predictions, to further advance the maturity of the acoustic modelling of such machines with complex three-dimensional features. The DES study investigates the influence of the inflation layers characteristics, and of the spatial resolution of the mesh, on the simulated acoustic signatures. In the core mesh, refinements are applied in areas of major acoustic production, to generate cells with sizes proportional to the local Taylor microscale values.
Technical Paper

Acoustic Study on Tubular Micro-perforated Flow Plug Sections in Vehicle Silencer’s Application

2022-06-15
2022-01-0933
Today, after a rapid publicity growth in the last decades, micro-perforated acoustic elements (MP) are widely applied for broadband sound absorption in internal combustion engine exhaust systems. Most typically the MP’s are exposed into a grazing flow conditions, for which a relatively good knowledge and respectable acoustic models exist. However, in certain exhaust system designs an alternative layout for tubular flow duct MP elements – the flow plug condition is useful. In this type of MP’s application all the exhaust gas flow is guided through the micro-perforated sections upstream and downstream of the plug, typically increasing the flow resistivity, and viscous damping of the propagating noise. This MP’s type also appears to be a considerably less studied one, whereas only a few dedicated papers can be found.
Technical Paper

Characterization and modelling of mounts for electric powertrains

2022-06-15
2022-01-0986
The topic of this paper is to deal with the filtering of medium and high frequency excitations generated by electrified powertrains. It is now recognized that the whining noise generated by the electromagnetic forces and/or the meshing process of the transmission can propagate to the car-body through the rubber mounts. In the design phase, the prediction of the structure borne contribution requires a good knowledge of the dynamic behavior of the rubber mounts. The main issue is the stiffness of the mounts which cannot be modeled as pure springs. In fact, the dynamic behavior of a mount is governed by the material rheology and its internal resonances. The work presented in this paper propose a simulation workflow for the rubber mounts dynamic model and a methodology for the dynamic stiffness measurement including the sensitivity with the preload and with the amplitude of the excitation. Finally, experimental and digital data are compared to assess the simulation method.
Technical Paper

End-Correction in Open Ducts: an Experimental Study

2022-06-15
2022-01-0987
This paper presents the results of an investigation on the influence of a duct’s geometry and shape on its acoustic length, which differs from its physical length by a factor referred to as end-correction. In addition to traditional parameters such as length and diameter, the author has investigated the effect of additional geometry features which are less commonly addressed in the technical literature, such as a diameter contraction or a bent section along the duct. The relative microphone position with respect to the pipe orifice and to the ground surface of the measurement environment has been investigated, showing negligible impact on the measurement results. The sound wave propagation within a pipe featuring a diameter contraction has then been analysed, showing the relationship between the pipe contraction shape and location and the pipe acoustic length.
Technical Paper

NVH Refinement of Automotive HVAC System

2022-06-15
2022-01-0982
The present day, car performance is more prevailing option to fascinate the buyer in IC and electric passenger vehicle. Acoustic and thermal performance balancing of heating ventilation and air conditioning (HVAC) system within car cabin proves to be critical aspect for automotive OEM. The HVAC system induced noise inside car cabin could be significant discomfort to passengers. For this reason, acoustic quality is becoming increasingly prioritized as a key design issue throughout the entire development process of HVAC system. The paper studies the advancement in using innovative development tools to map the HVAC system noise performance at vehicle level and evaluating at sub component level for noise, vibration and transient flow of refrigerant fluid induced noise with the help of universal buck under controlled condition.
Technical Paper

On the different contributions of mounts and flexible hoses on the structure borne noise of refrigerant compressors

2022-06-15
2022-01-0983
Air conditioning acoustics have become of paramount importance in electric vehicles, where noise from electromechanical components is no longer masked by the presence of the internal combustion engine. The coolant compressor is one of the most important elements in the HVAC systems of a car in terms of vibration and noise generation. The generated structural noise is studied in detail in a prototype installation, and the noise transmission and propagation mechanisms are analyzed and discussed. Through ”in situ” measurements and virtual point transformation the rotor unbalance forces and torques acting within the component are identified. The dynamic properties of the rubber mounts installed between the compressor and its support are identified thanks to matrix inversion methods. To assess the quality of the proposed procedure, the synthesised sound pressure level (SPL) is compared with experimental (SPL) measurements in different operational conditions.
Technical Paper

Prediction and Optimization of Blocked Force Changes of a Suspension System using Bush Stiffness Injection Method

2022-06-15
2022-01-0956
Automotive OEMs have introduced a new development paradigm, modular architecture development, to improve diversity quality and production efficiency. It needs solid fundamentals of system-based performance evaluation and development for each system level and single component level. When it comes to NVH development, it is challenging to realize the modular concept because noise and vibration should be transferred through various transfer path consisting of many parts and systems, which interact with each other. It is challenging for a single system of interest to be evaluated independently of the adjacent parts and environments. In this study, a new system-based development process for a vehicle suspension was investigated by applying blocked force theory and FRF-based dynamic substructuring. The objective is to determine the better dynamic stiffness distribution of many bushes installed in a suspension system in the frequency range corresponding to road noise.
Technical Paper

High-bandwidth Mechanical Hardware-in-the-Loop Emulation of Structural Dynamics for More Efficient NVH Development and Testing

2022-06-15
2022-01-0953
Numerical simulations offer a wide range of benefits. Therefore, they are widely used in research and development. One of the biggest benefits is the possibility of automated parameter variation. This allows testing different scenarios in a very short period of time. Nevertheless, physical experiments in the laboratory or on a test rig are still necessary and will still be necessary in the future. The physical experiments offer benefits e.g. for very complex and/or nonlinear systems and are needed for the validation of numerical models. In order to enhance the quality of experimental NVH investigations and to make use of the benefits numerical simulation during experimental investigations at the same time, numerical models can be integrated into physical test rigs by means of the mechanical hardware-in-the-loop (mHIL) method (also referred to as real-time dynamic substructuring, hybrid testing or active control of impedance).
Technical Paper

Experimental characterization and dynamic modelling of electrical cables

2022-06-15
2022-01-0952
Electric high voltage (HV) cables are commonly used in electrified vehicles. These cables are well known for being potential flanking transmission paths for structure-borne sound in a broad frequency range and must therefore be included in the NVH design process. Although many different layouts exist automotive HV cables fundamentally exhibit a layered structure consisting of a conductive core covered by, in sequence, an isolating sheath, a wire mesh shield to minimize electromagnetic interference and an outer jacket. The conductive core consists of hundreds of thin copper or aluminum wires organized in strands which are wound in a helical pattern. An extensive measurement campaign was carried out to dynamically characterize different cable specimen in terms of multi-degree of freedom transfer impedances.
Technical Paper

ANC: A Low-cost Implementation Perspective

2022-06-15
2022-01-0967
In the present work, we describe a low-cost implementation of an Active Noise Cancellation (ANC) system. The most interesting feature of our implementation is the use of general-purpose hardware, without the need of expensive and hard-to-program Digital Signal Processing (DSP) devices. In particular, the reference signals, collected with accelerometers properly placed on noise-generating parts and the error feedback signals are collected by means of an USB interface. All signal processing, aimed at primary path estimation and anti-noise audio signal generation, is performed using Simulink running on a commercial mini PC. The Exponential Sine Sweep (ESS) method is adopted for the measurement of the secondary path from the cancellation loudspeakers to the error microphones. An adaptive Filtered-X Least Mean Square (LMS) algorithm determines the anti-noise audio signal to be emitted.
Technical Paper

Mixture Formation Analysis for Diesel, n-Dodecane, RME, and HVO in Large-Scale Injector Nozzles

2022-06-14
2022-37-0019
Momentum conservation is a principle rule that affects the behaviour of vapour jet and liquid spray penetration. The air entrainment and mixture formation processes are dominated by the momentum transferred from the fuel to the ambient gas. Thus, it is a significant factor in the development of spray and jet penetration. This mixture formation process is well described for small-scale passenger car injectors; however, it has to be investigated in more detail for large-scale injector nozzles. It is the aim of this study to evaluate this process. The current work provides qualitative and quantitative results of spray and jet parameters in a constant volume combustion chamber (CVC). Two optical methods have been utilized to evaluate spray and jet details: Schlieren photography as a method to visualize the jet penetration and cone angle as well as Mie scattering for the phase change evaluation and the determination of liquid spray parameters.
Technical Paper

Model based design, prototyping and testing of a very small size electrically driven centrifugal pump

2022-06-14
2022-37-0025
Within automotive sector, there are several high-performance applications, like, for instance, those referred to racing and motorsport, where cooling needs are usually fulfilled by simple circuits with conventional low-efficiency pumps. The cooling needs in these applications are represented by low flow rates delivered and pressure ratios which depends on the permeability of the circuits. The operating conditions of these pumps are usually characterized by very high revolution speeds which intrinsically causes a low efficiency and critical intake phenomena (cavitation). The high speed of revolution requested by the reduced space available on board invites to consider an electrical actuation which avoids mechanical connections with the engine and produces very integrated and compact solutions guaranteeing interesting cooling performances useful also for more conventional engines (thermal management due to the electrical actuation of the pump).
Technical Paper

Mixture Formation Analysis for Diesel, n-Dodecane, RME, and HVO in Large-Scale Injector Nozzles

2022-06-14
2022-37-0020
Momentum conservation is a principle rule that affects the behaviour of vapour jet and liquid spray penetration. The air entrainment and mixture formation processes are dominated by the momentum transferred from the fuel to the ambient gas. Thus, it is a significant factor in the development of spray and jet penetration. This mixture formation process is well described for small-scale passenger car injectors; however, it has to be investigated in more detail for large-scale injector nozzles. It is the aim of this study to evaluate this process. The current work provides qualitative and quantitative results of spray and jet parameters in a constant volume combustion chamber (CVC). Two optical methods have been utilized to evaluate spray and jet details: Schlieren photography as a method to visualize the jet penetration and cone angle as well as Mie scattering for the phase change evaluation and the determination of liquid spray parameters.
Technical Paper

Unmanned Aerial Solution for Ecological Mapping Surveillance

2022-05-26
2022-26-0026
The proposed UAV can be used to triangulate the areas of unnatural deforestation, by processing the areas undergoing land cover transition. Thus, restraining illegal logging and deforestation and, ultimately, facilitating the ecological succession cycle. It identifies the green cover which helps in predicting the population of the feeding animal species and the biodiversity. The system will be influential for curbing the exploitation of landscapes with heterogeneous habitats and diverse topographical features. The model employs onboard automated controller - ARDUPILOT MissionPlanner, a flight controller, GPS and telemetry module. The setup collects data from the controller such as Altitude, GPS location, Pitch, Roll, etc. and transmits it to the Ground Control Station (GCS) during cruise. The mission planner is programmed by selecting the target survey area which is divided into a grid, Home which is the launch point and Waypoints which will be crossed autonomously.
Technical Paper

Lives Saved by Accelerating the Implementation of Vehicle Safety Technology in New South Wales

2022-05-20
2021-22-0001
Australian vehicle standards are governed nationwide by the Australian Design Rules (ADR) that specify regulatory standards for the safety performance of road vehicles. The aim of this study was to quantify the number of lives saved on New South Wales roads by accelerating the update of safer vehicles by aligning ADR with global best practice represented by the new European Union General Safety Regulation. The methods used in this study to estimate the impact of future road safety interventions was a logical reduction of current crashes into future casualty outcomes, the residual, based on what is known about delivery of future safety measures and system improvements. A database was prepared including information on all 2018 fatalities on NSW roads (n=347). The database contained information for each individual crash, the vehicles and persons involved and the road environment where the crash occurred.
Technical Paper

Instantaneous Brain Strain Estimation for Automotive Head Impacts via Deep Learning

2022-05-20
2021-22-0006
Efficient brain strain estimation is critical for routine application of a head injury model. Lately, a convolutional neural network (CNN) has been successfully developed to estimate spatially detailed brain strains instantly and accurately in contact sports. Here, we extend its application to automotive head impacts, where impact profiles are typically more complex with longer durations. Head impact kinematics (N=458) from two public databases were used to generate augmented impacts (N=2694). They were simulated using the anisotropic Worcester Head Injury Model (WHIM) V1.0, which provided baseline elementwise peak maximum principal strain (MPS). For each augmented impact, rotational velocity (vrot) and the corresponding rotational acceleration (arot) profiles were concatenated as static images to serve as CNN input.
Standard

Automotive Gear Lubricants for Commercial and Military Use

2022-05-20
CURRENT
J2360_202205
The gear lubricants covered by this standard exceed American Petroleum Institute (API) Service Classification API GL-5 and are intended for hypoid-type, automotive gear units, operating under conditions of high-speed/shock load and low-speed/high-torque. These lubricants may be appropriate for other gear applications where the position of the shafts relative to each other and the type of gear flank contact involve a large percentage of sliding contact. Such applications typically require extreme pressure (EP) additives to prevent the adhesion and subsequent tearing away of material from the loaded gear flanks. These lubricants are not appropriate for the lubrication of worm gears. Appendix A is a mandatory part of this standard. The information contained in Appendix A is intended for the demonstration of compliance with the requirements of this standard and for listing on the Qualified Products List (QPL) administered by the Lubricant Review Institute (LRI).
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