Browse Topic: Scale models

Items (924)

Electric Powertrain - Standardization of Adaptable Software in Loop System

2024-26-011701/16/2024

Motivation With an increase in the complexity involved in modern-day ECUs (Electronic Control Unit), it is very important to verify and validate robustness, functionality, and reliability of ECUs. Till date, Hardware in Loop (HiL) based validation or vehicle level validation is generalized approach used for testing. However, this method requires physical setup, which can incur more cost and time during the development phase. Solution We believe in minimizing the software testing time using Software in Loop (SiL) validation. Creating virtual-ECUs and the plant models is an important step in SiL. We are presenting the modularized and scalable plant models in this paper. Adaptable SiL Solution for EV This paper focuses on the standardization of electric vehicle plant models, which can help users to reduce the software development and software testing time. We created the standardized plant models for following virtual ECUs, which can be used as modular units. • Battery Management System

Sajnani, Abhishek, Vernekar, Kiran, Gosavi, Rupesh, Naik, Venkatesh

Computational Investigation of a Flexible Airframe Taxiing Over an Uneven Runway for Aircraft Vibration Testing

01-17-02-0011

12/15/2023

Ground vibration testing (GVT) is an important phase of the development, or the structural modification of an aircraft program. The modes of vibration and their associated parameters extracted from the GVT are used to modify the structural model of the aircraft to make more reliable dynamics predictions to satisfy certification authorities. Due to the high cost and the extensive preparations for such tests, a new method of vibration testing called taxi vibration testing (TVT) rooted in operational modal analysis (OMA) was recently proposed and investigated by the German Institute for Aerospace Research (DLR) as alternative to conventional GVT. In this investigation, a computational framework based on fully coupled flexible multibody dynamics for TVT is presented to further investigate the applicability of the TVT to flexible airframes. The time domain decomposition (TDD) method for OMA was used to postprocess the response of the airframe during a TVT. The framework was then used to

Al-bess, Lohay, Khouli, Fidel

Friction Performance Analysis of Mine Wet Multi-Disc Brake

02-17-01-0001

10/28/2023

Abstract This article takes the wet multi-disc brake used in mining Isuzu 600P as the research object, establishes a simplified three-dimensional model of its key components through SOLIDWORKS and imports it into ANSYS Workbench to establish the flow field and structure field model of the wet brake. Based on the fluid–solid coupling, the finite element simulation of the temperature field and stress field of the friction pair of the wet brake under different braking pressures, braking initial speeds, and fluid viscosities was carried out, and then the position changes of the friction pairs at high temperature hot spots and high stress points were analyzed to determine the stability of its friction performance. Finally, by comparing the temperature change curves of the same point during the braking process under different braking conditions, the validity of the finite element analysis results is verified. The results show that the flow field pressure inside the wet brake is opposite to

Zhang, Chuanwei, Jin, Xiaohe, Zhao, Dawei, Liu, Jinpeng

Correlation of NVH Model for Extended Range Generator in Electric Vehicle

2025-01-007705/05/2023

As electrification becomes more common in the automotive industry, the need to accurately predict their behavior in the prototyping phase has become a critical topic for manufacturers. Electric motors are naturally much quieter than combustion engines, and as a result there is an increased emphasis on the reduction of noise, vibration, and harshness (NVH). This emphasis carries over into a need for accurate, quantitative prediction of NVH phenomena. This need applies not only when comparing performance between variants, but for confidently driving design decisions to meet customer satisfaction. Furthermore, accurate prediction is critical because NVH performance must be balanced with other areas such as durability and eMotor performance. If the NVH response is not accurate, one cannot take the appropriate countermeasures. In some cases this can lead to a noisy eMotor. In other cases, a poorly performing, very quiet eMotor This paper presents a comprehensive approach to addressing this

Huang, Fatao, Proben, Joel, Pasagada, Keerti Vardhan, Hilty, Drew

"Operation Strategies of Heat Pump Systems in High-Performance Electric Vehicles"

1329909/15/2022

"The energy consumption of a thermal management system cannot be neglected and is a significant contributor compared to the total energy consumption of a battery electric vehicle. Using a heat pump as part of the thermal management system, can heat and reduce energy consumption at low ambient temperatures. A state-of-the-art heat pump system consists of numerous actuators such as fans, pumps, electrical heater, compressor, and valves. An existing challenge remains to develop efficient operational strategies for these components with the corresponding interactions in dynamic boundary conditions. A physical model of the system can be used to optimize the control method and consequently, helps to save energy. The objective of this investigation is to obtain an operating strategy, which efficiently distributes the electric power between the heat pump compressor and the electric heater. In this context, the influence of an optimized, model-based control of the compressor speed on the

Hug, Thimo

Dynamic Vehicle-in-the-Loop: A Novel Method for Testing Automated Driving Functions

12-05-04-002906/23/2022

In automated driving functions (ADF) testing, novel methods have been developed to allow the combination of hardware and simulation to ensure safety in usage even at an early stage of development. This article proposes an architecture to integrate an entire test vehicle—denominated Dynamic Vehicle-in-the-Loop (DynViL)—in a virtual environment. This approach enables the interaction of a real vehicle with virtual traffic participants. The vehicle is physically tested on an empty track, but connected to the CARLA simulator, in which virtual driving scenarios are created. The simulated environment is transmitted to the vehicle driving function which controls the real vehicle in reaction to the virtual objects perceived in simulation. Furthermore, the performance of the DynViL in different test scenarios is evaluated. The results show that the reproducibility of the tests with the DynViL is satisfactory. Furthermore, the results indicate that the deviation between simulation and DynViL

Drechsler, Maikol Funk, Sharma, Varun, Reway, Fabio, Schütz, Christoph, Huber, Werner

Model Based Design (MBD): An Engineering approach for system design

2022-26-117105/26/2022

Modelling and simulation are powerful tool for analysis of new system design. Model based design is an engineering approach that uses models as an important tool for design, analysis, implementation, testing and validation of a system or product. It is a mathematical and visual method of addressing problems associated with designing complex control, signal processing and communication systems. This paper focuses on model-based design approach using MATLAB Simulink. Also, a case study is discussed where mathematical models are discussed in order to design a EV Powertrain. Development of a dynamic model to investigate the behavior of an electric motor based on torque varying characteristics. The discussion in this paper revolves around equation-based modelling of the vehicle drivetrain, motor and battery subsystem. The models result into vehicle torque, motor torque, motor current and voltage requirements and also the battery sizing as well. Based on the powertrain requirements resulted

Dhurjad, Shubham, KHAINAR, SWARAJ, Kashid, SWARAJ, LAHURIKAR, ASITANG, GORAD, PARTH

Adaptive control of self-humidification PEM fuel cell system based on cathode recirculation

2022-01-083103/29/2022

The distribution of the water content and reactant concentration has an important impact on the durability and output performance of the PEM fuel cell system. Especially for a self-humidification fuel cell system, membrane drying or local liquid water accumulation will cause poor output performance and even lead to irreversible damage to the stack. To prolong the stack lifespan and achieve the best output performance, it is important to construct a balanced water circulation in the fuel cell stack by actively controlling external subsystems and optimizing operating conditions. In this study, a three-dimensional model of the fuel cell stack is modeled by the ANSYS fluent where the distributions of stack internal states are calculated and illustrated and the external subsystem such as hydrogen supply subsystem, air supply subsystem and thermal management system are modeled on the MATLAB/SIMULINK platform. With the FLUENT/SIMULINK co- simulation, the internal states of the fuel cell stack

Yu, Yang, Jiao, Jieran, chen, fengxiang

Pseudo Transient Torque Converter Clutch Engagement Process Using Fluid-Structure Interaction Simulation

2022-01-078103/29/2022

This investigation utilizes a correlated fluid-structure interaction (FSI) model of the torque converter and clutch assembly to perform a pseudo transient clutch engagement at steady state operating conditions. The pseudo transient condition consists of a series of nine steady state simulations that transition the torque converter clutch from fully released to near full lockup at a constant input torque and output speed representative of a highway cruising speed. The flow and pressured field of the torque converter torus and clutch are solved using a CFD model and then passed along to a transient structural model to determine the torque capacity of the lockup clutch. Bulk property assumptions regarding the friction material, deformation of the clutch plate and deflection of supporting structures were made to simplify the model setup, run time and solution convergence. Telemetry pressure measurements acquired in an operating torque converter under similar operating conditions on a

Beldar, Aniket, Robinette, Darrell, Blough, Jason

Databased modeling: An AI Toolchain for the development process of combustion engines

2022-01-018803/29/2022

Predictive physical modeling is an established method used in the development process for any automotive component or system. While accurate predictions can be issued after tuning model parameters, long computation times can be expected depending on the complexity of the model at hand. As the requirements of the components/systems to be developed continuously increase, new optimization approaches are constantly being applied to solve multidimensional objectives and resulting conflicts optimally. Unfortunately, some of those approaches are deemed not feasible, as the computational times of the required single predictions using conventional simulation models are too high. Therefore, it is proposed to use data-based models such as trained neural networks instead of physical models to address this issue. Previous efforts have failed due to a weak database and the resulting poor predictive ability of data-based models. This paper introduces an AI Toolchain used for data-based modeling of

Milojević, Sasa, Rether, Dominik, Bodza, Sebasian, Grill, Michael, Angerbauer, Michael, Bargende, Michael, Cimniak, Valerian

DFSS Optimization of Vehicle IIHS Small Overlap Rigid Barrier (SORB) Impact Performance Using a Simplified Spring-Mass CAE Model

2022-01-093503/29/2022

In the modern practice of the vehicle crashworthy design development and its impact performance validation, virtual full vehicle crash models have been widely and successfully utilized as the analysis tool by many safety CAE engineers. Recently, a typical full-vehicle front impact model has grown in size up to over 3 million finite elements to enable analysis of highly localized and transient responses of vehicle structure deformation under the impulsive loads. This full vehicle model takes 10 ~15 computer hours per run even on a fast Massively Parallel Process(MPP) server. The CPU time will increase if the full-vehicle model is applied for analysis of the offset-barrier events in which the test vehicle receives barrier impact loading for a longer duration. Furthermore, for a design optimization task running a large DOE variation matrix, the total turn-around time including CPU hours taken for the DOE model iterations could rise significantly depending on the number of the control

Park, Sae U., Hor, Hassan, Rajagopalan, Rajkumar, Kleinhoffer, Stacey, Westra, Michael

A Bayesian method for load identification of powertrain mounting system with interval uncertainty

2022-01-074603/29/2022

It is very important to accurately identify the load of the vehicle in the working state for the study of vehicle vibration and noise. At present, the identification technology of dynamic load mainly focuses on the deterministic model, but there are always structural model errors in practical engineering. Bayesian method and interval theory can deal with unknown-but-bounded uncertainties in measurement noise and structural systems. In this paper, a time domain load identification method based on Gibbs sampling and a hybrid dynamic load identification method based on Bayesian and interval analysis are proposed. Firstly, the structural model error is considered as the overall Markov parameter matrix error, and the measurement noise is calculated together; secondly, considering the structural model error as interval parameter, the upper and lower load boundaries are obtained by combining interval analysis with Gibbs sampling method based on Taylor expansion. It is shown that the Gibbs

gao, bo, Liu PhD, Xiaoang

The Effect of Unsteady Incident Flow on Drag Measurements for Different Vehicle Geometries in an Open Jet Wind Tunnel

2022-01-109003/29/2022

Automotive engineers use the wind tunnel to improve a vehicle’s aerodynamic properties on the road. However, a car driving on the road does not experience the steady-state, uniform flow characteristic of the wind tunnel. Wind, terrain and traffic all cause the flow experienced by the vehicle to be highly transient. Therefore, it is imperative to understand the effects of unsteady flow on the forces the vehicle experiences. To this end, the FKFS swing® installed in the University of Stuttgart’s model scale wind tunnel was used to create 36 different incident flow signals with time-resolved yaw angles. The cD values of five different 25% vehicle models, each with a notchback and a squareback configuration, were measured while under the influence of the aforementioned signals. The vehicle models were chosen to ensure a variety of different geometries, but at the same time also to enable isolated comparison of specific geometric properties. All drag measurements were corrected using the

Fei, Xiao, Kuthada, Timo, Wagner, Andreas, Wiedemann, Jochen

Experimental Investigation of the Wake Structure of the Generic Truck Utility with Correlation to Common Numerical Models for Simulating Turbulence

2022-01-108303/29/2022

The aerodynamic forces on bluff body vehicles are often dominated by off-body flow structures in the downstream wake of the vehicle, however attempts to correlate computational methods to the real-world have typically relied on surface pressures and integral forces. The Generic Truck Utility (GTU) was developed to provide a more realistic test box for understanding the aerodynamics of such vehicles. In this study the GTU geometry has been used to build a scale model for wind tunnel testing with wake measurements to compare to a range of results from computational fluid dynamics (CFD). The wind tunnel data includes integral forces, surface pressures and wake measurements of total pressure. The CFD results include a range of RANS turbulence models from one-equation Spalart-Allmaras to more recent elliptic-blending models as well as transient DES results, all run across meshes of increasing refinement in the wake region. Some interesting observations on mesh sensitivity can be made for

Mosedale, Andrew, Pithwa, Prem

eFMI (FMI for embedded systems) in AUTOSAR for Next Generation Automotive Software Development

2021-26-004809/22/2021

Nowadays automobiles are getting smart and there is a growing need for the physical behavior to become part of its software. This behavior can be described in a compact form by differential equations obtained from modeling and simulation tools. In the offline simulation domain the Functional Mockup Interface (FMI), a popular standard today supported by most of the tools, allows to integrate a model with solver (Co-Simulation FMU) into another simulation environment. These models cannot be directly integrated with embedded automotive software due to special restrictions with respect to hard real-time constraints and MISRA compliance. Another architectural restriction is organizing software components according to the AUTOSAR standard which is typically not supported by the physical modeling tools. On the other hand AUTOSAR generating tools do not have the required advanced symbolic and numerical features to process differential equations. In order to bridge the gap to the embedded world

Armugham, Siva Sankar, Lenord, Oliver, Werther, Kai, Bertsch, Christian, Ramachandran, Karthikeyan

Virtually Evaluated Welds for BSVI Powertrain Components and Physically Correlated for First Time Right Designs

2021-26-042009/22/2021

Virtual validation of automobile components poses a huge challenge and needs continuous process improvements. One of such challenge in FE modelling of welds and understanding its behavior with respect to physical behavior. With the ongoing development of BSVI line of products in commercial vehicle industry, the virtual validation needs to be accurate and close to the physical behavior of the components. The learning and challenges faced in the BSIV range needs to be implemented and improvised in BSVI range. The Brackets welded to the power train components has taken as a challenge in the present work. Initially welds used to be modeled in the CAD itself, which has been analyzed in CAE by providing proper FE connection. This practice had lot of flaws, approximations due to perpendicularity and flatness concerns in the models with a high usage of a time. But as per market trends, every product needs to be launch on time with first time right design slogan. Using SIMLAB tool by ALTAIR

Nishad, Hemant Kumar, Kandreegula, Suresh Kumar, Jadhav, Santosh, H A, Mithun

Techniques to evaluate Energy Efficiency and Performance of an Electric Vehicle by leveraging Co-simulation

2021-26-036709/22/2021

After designing any Powertrain component/subsystem for a conventional or an Electric vehicle, System Energy efficiency and Performance improvement Simulations are an very important step to prove the worthiness of the product before we can go for Prototypes, Vehicle level Integration, Testing 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 modeling tool for building vehicle level models. This tool has readymade physical component 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 Inertias and the Multi-speed transmission consisting of various mechanical elements have been modeled and parameterized using this tool. This tool is the front end of the Co-simulation. The Physical model is

Iyer, Ramkumar, Chen, Zhichao, SATYANARAYANA, PS, BHATTACHARJEE, ANTARA, JHA, NAVNEET, Ramalingam, Gomathi

Accurate Steering system modeling for Vehicle Handling and Steering performance prediction using CAE

2021-26-040309/22/2021

The car industry strives to develop high-quality vehicles quickly that fulfill the buyer's needs and stand out within the competition. Full utilization of simulation and Computer-Aided Engineering (CAE) tools can empower quick assessment of different vehicle concepts and setups without building physical models. Vehicle execution assessment is critical in the vehicle development process, requiring exact vehicle steering system models. The effect of steering system stiffness is vital for vehicle handling, stability, and steering performance studies. The overall steering stiffness are usually not modeled accurately. Usually torsion bar stiffness alone is considered in modeling. The modeling of overall steering stiffness along with torsion bar stiffness is studied in this paper. Another major contributing factor for steering performance is steering friction. The steering friction is also often not considered properly. This paper present the modeling of steering stiffness and friction

Ganesh, Lingadalu, Hg, Pavan Prasad, N, BALARAMAKRISHNA

A physical model for driveshaft vibration transmissibility

2021-01-111208/31/2021

The driveshafts can be an important contributor to vehicle interior noise including low-frequency (booming) noise where the vibrations, originating in the powerplant, travel to the vehicle body through the driveshafts. A suitable KPI for the driveshaft performance is the transmissibility, which is an output/input acceleration ratio and can be used to describe the amount of vibration transferred from the inboard to the outboard joint of the driveshaft. This paper introduces a simple physical model of the driveshaft transmissibility able to support the development and evaluation of the driveshaft and to estimate the effectiveness of countermeasures such as a dynamic damper. The model is validated through comparison with on-vehicle measurements. The proposed approach offers ease of use, low computational cost and clear relation of the measured transmissibility with the system’s physical properties. Good accuracy can be obtained for the booming noise range, especially if the driveshaft

Bafouni - Kotta, Anastasia, Bergen, Bart, Van de Rostyne, Kris, Nikolakopoulos, Pantelis

Analytical Methods for Aircraft Seat Design and Evaluation

ARP5765B (Current)

03/30/2021

This SAE Aerospace Recommended Practice (ARP) defines a means of assessing the credibility of computer models of aircraft seating systems used to simulate dynamic impact conditions set forth in Title 14, Code of Federal Regulations (14 CFR) Parts 23.562, 25.562, 27.562, and 29.562. The ARP is applicable to lumped mass and detailed finite element seat models. This includes specifications and performance criteria for aviation specific virtual anthropomorphic test devices (v-ATDs). This document provides a recommended methodology to evaluate the degree of correlation between a seat model and dynamic impact tests. This ARP also provides best practices for testing and modeling designed to support the implementation of analytical models of aircraft seat systems. Supporting information within this document includes procedures for the quantitative comparison of test and simulation results, as well as test summaries for data generated to support the development of v-ATDs and a sample v-ATD

Aircraft SEAT Committee

Analytical Methods for Aircraft Seat Design and Evaluation

ARP5765B-TEST-REC (Historical)03/30/2021

Aircraft SEAT Committee

The Prospect and Benefits of Using the Partial-Averaged Navier-Stokes Method for Engine Flows

2020-01-110704/14/2020

This paper presents calculations of engine flows by using the Partially-Averaged Navier Stokes (PANS) method (Girimaji [1]; [2]). The PANS is a scale-resolving turbulence computational approach designed to resolve large scale fluctuations and model the remainder with appropriate closures. Depending upon the prescribed cut-off length (filter width) the method adjusts seamlessly from the Reynolds-Averaged Navier-Stokes (RANS) to the Direct Numerical Solution (DNS) of the Navier-Stokes equations. The PANS method was successfully used for many applications but mainly on static geometries, e.g. Basara et al. [3]; [4]. This is due to the calculation of the cut-off control parameter which requires that the resolved kinetic energy is known and this is usually obtained by suitably averaging of the resolved field. Such averaging process is expensive and impractical for engines as it would require averaging per cycles. A recently published work on PANS (Basara et al. [5]) opens a prospect of more

Basara, Branislav, Pavlovic, Zoran, Girimaji, Sharath

Second-Order Sliding Mode Controller for Performance Analysis of Quarter Car Magnetorheological Suspension System

2020-01-100504/14/2020

To achieve the simultaneous improvement in ride comfort of the passenger as well as the stability of the vehicle, a second-order sliding mode controller is proposed in this study. Super twisting algorithm attenuates the chattering effect present in the conventional sliding mode controller without affecting the stability of the system. The Lyapunov stability analysis is carried out to verify the stability of the controller. The effectiveness of the designed super twisting algorithm used second-order sliding mode controller is validated in a semiactive quarter car suspension with seat model. Modified Bouc-wen magnetorheological (MR) damper model is used as a semiactive damper and the voltage that has to be supplied to the magnetorheological damper is controlled by a super twisting algorithm and sliding mode controller. Continuous modulation filtering algorithm is adopted to convert the force signal of a controller into the equivalent voltage input to the MR damper. The entire system is

Soosairaj, Arockia Suthan, K, Arunachalam

A Pre-Warning Method for Cornering Speed of Concrete Mixer Truck

2020-01-100304/14/2020

The high gravity center of the concrete mixer truck reduces the truck’s stability while steering. The rolling stirring tank makes the stability even worse than the regular engineering vehicle due to the dynamic variation of the centroid position. Most of the researches on the rollover stability of concrete mixer trucks focus on the rollover model establishment and dynamic simulation module. The change of concrete centroid is ignored when the safety cornering speed is calculated. This paper proposes a pre-warning method for the cornering speed of concrete mixer trucks based on centroid dynamic simulation. In the method, the mixing tank stirring model and the vehicle driving dynamic model are established on the Fluent and TruckSim simulation platforms, respectively. The theoretical speed threshold obtained by simulation is used as the evaluation index of the warning speed in the curve. Firstly, the dynamic simulation of the stirring tank model is carried out by Fluent. According to

Jiang, Yifeng, Tan, Gangfeng, Wang, Haoyu, Wang, Zelong, Wang, Zhenyu, Li, Ming

Defining Fundamental Vehicle Actions for the Development of Automated Driving Systems

2020-01-071204/14/2020

Automated Driving Systems (ADSs) show great potential to improve our transport systems. Safety validation, before market launch, is challenging due to the large number of miles required to gather enough evidence for a proven in use argumentation. Hence there is ongoing research to find more effective ways of verifying and validating the safety of ADSs. It is crucial both for the design as well as the validation to have a good understanding of the environment of the ADS. A natural way of characterizing the external conditions is by modelling and analysing data from real traffic. Towards this end, we present a framework with the primary ultimate objective to completely model and quantify the statistically relevant actions that other vehicles conduct on motorways. Two categories of fundamental actions are identified by recognising that a vehicle can only move longitudinally and laterally. The fundamental actions are defined in detail to create a set that is collectively exhaustive and

Gyllenhammar, Magnus, Zandén, Carl, Törngren, Martin

A Platform for Quick Development, Simulation and Test of Autonomous Driving Vehicles

2020-01-071304/14/2020

This paper proposes a platform to conduct rapid development, simulation and test of autonomous driving vehicles. By combining the advantages of rapid prototyping and software development, the proposed platform could automatically generate codes and download them into domain controllers, therefore the efficiency of development process of the core functions of ADAS can be largely improved. The platform is made up of scene simulation, vehicle dynamics simulation software, a rapid prototyping system, a chassis drive-by-wire control and road-load simulation system. Meaningful tasks including key algorithm development, MIL simulations, domain controller based HIL tests and the development of drive-by-wire systems can all be accomplished by the platform. Since that the E/E architecture of vehicles, intra-vehicle communication and physical characteristics of drive-by-wire systems are well considered, the platform ensures that the developed domain controllers can be directly deployed to road

Qiong, Wu, Man, Adm Jiang Jian, Wei, Liang Hua, Bing, Li Wei

Accounting Thermal Exchanges in Coanda Effect

2020-01-0026

03/10/2020

An exhaustive model of Coandã effect has not been defined, and fundamental questions are still open. One of them is the influence of convective heat exchange on Coandã adhesion. This paper presents an even preliminary numerical study of this problem. It analyses the behaviour of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface. It approaches the problem by a set of CFD simulations, analyses previous hypotheses, which are based on Prandtl number, and evidences the need for a model that account Reynolds number. The performed simulations are still not sufficient for an exhaustive comprehension of Coandã effect in the presence of heat exchange phenomena. It allows producing some consideration that may help future scientific work in toward a better comprehension of these phenomena. In particular, it verifies the importance of Reynolds number, because it is intrinsic in the adopted model, with good accordance with CFD data

Trancossi, Michele, Pascoa, Jose