bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Cooling Air Flow for Improved Heat Dissipation through Radiator
Authors: Palve Chandrakant , Thakur Paurnima , Chavan Vishal , Aher Amit
Published: January 2024

Environmental Protection Agency (EPA) study indicates that a typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year. The Automotive industry facing a challenge of meeting stringent CO2 emission targets of 95g per kilometer for passenger car application. Thermal efficiency of internal combustion engine is one of the crucial technical parameters, which plays an important role in meeting CO2 emission targets. Global Automotive industry tends to achieve for cleaner, lower emission, low noise & improved performance for automotive products. Engine Overheating is affecting thermal efficiency & thus brake specific fuel consumption of the vehicle. Radiator is one of the critical components in Engine cooling system, which will ensure optimum operating range of internal combustion engine through precise control on coolant flow rate by Thermostat valve. Heat dissipation through radiator is directly proportional to volumetric mass flow rate of atmospheric air. The demand for more powerful engines in smaller hood spaces has created a problem of insufficient rates of heat dissipation in automotive radiators. Upwards of 33% of the energy generated by the engine through combustion is lost in heat. By taking motivation from this strategic challenge, innovative concept had proposed with mechanical & automatic layout.
Virtual Test Bed (VTB) Based Engine Calibration: Unique Approach to Ensure Engine Component Protection & to Meet WNTE in Different Environment Condition for Medium Duty Diesel Engine
Authors: Sharma Ajeet Kumar , Arora Prateek , Vos Bas , Goyal Dinesh
Published: January 2024

In view of BS-VI emission norms implementation in Commercial Vehicle (CV) application, the emissions are not only confirmed in standard condition but also in non-standard condition including different combinations of ambient temperature and pressure especially for checking the emission in WNTE cycle. However, achieving the emissions in different environmental conditions require physical emission calibration to be performed in those conditions. Hence, engine must be calibrated in climatic test chambers to ensure emission in different climatic conditions leading to multifold increase in the calibration effort.

With addition of BS-VI emission regulation, After Treatment System (ATS) is a mandatory requirement to reduce the tail pipe emissions. Efficient functioning of ATS requires enough heating to convert the engine out emissions. Vehicle level Real Drive Emission (RDE) measurement without Conformity Factor (CF) limitation are added as an important legislative requirement. However, in commercial vehicle application the single engine configuration is used for different vehicle applications. These vehicles are having different speed and load profiles and varying ATS layouts. Therefore, robust thermal measures are required to ensure adequate heating of ATS under various climatic condition with worst case of ATS layout and vehicle load profile. The thermal measures stress the engine components to work on design limits, thus engine must operate steadily and provide adequate heat to ATS under extreme climatic application. This calls for a robust engine component protection in varying climatic conditions.

In this paper a calibration methodology is discussed to calibrate the medium duty diesel engine for robust component protection in different climatic conditions (varying environment pressure and temperature), also to calibrate robust thermal measures to ensure sufficient heating of ATS while minimizing the efforts applied in climatic test bed calibration and achieving significant time reduction in vehicle validation. Hence with this approach a considerable cost and vehicle validation time could be saved with providing robust calibration.
Cab RLDA Using VI & MI Approach: A Co-Simulation of ADAMS/Acar & FEMFAT Lab VI/MI
Authors: Singh Prempal , Prasad Tej
Published: January 2024

The current approach of hybrid RLDA is typically incapable of providing accurate dynamic loads coming on cab at chassis-to-cab load transfer locations, primarily due to the following two reasons. Firstly, all of the model parameters of the vehicle, which is put on the 4-post, are not known. Secondly, MBS (Multi-body System) Cab model is multi degree of freedom with rigid bodies, flex bodies, contacts and non-linear force elements. Therefore, if the system identification is to be performed manually it becomes an arduous and humanly impossible task.

Towards generating accurate dynamic loads on cab, an approach using FEMFAT LAB - VI & MI has been developed which involves a two-step process: a) Generating MBS excitation by back calculating from measured frame response – VI (Virtual iterations). b) Fine tuning modelling parameters to match measured cab response – MI (Model Improvement). To execute the VI & MI approach for calculating dynamic loads on cab through 4-poster & 7-poster simulation, measured road data (load, acceleration, displacement etc.) is required. Road data has been acquired on a Tata vehicle at strategically identified locations on various test tracks in two different loading conditions. The flexible MBS model had been created in MSC-ADAMS/Acar for 4-poster & 7-poster simulations. MBS excitation signal is back calculated from measured frame response through VI approach in FEMFAT Lab-VI tool and improvement in accuracy is demonstrated through correlation between simulated v/s measured cab & frame responses, in terms of relative damage. Furthermore, Model Improvement (MI) is done by updating relevant parameters identified by a diagnose tool to improve the correlation level. Finally, the improvement in accuracy of simulated outputs using VI & MI approach over existing process is also demonstrated.
A Methodology of Optimizing Steering Geometry for Minimizing Steering Errors
Authors: Sahare Vrushabh Umesh , Vichare Chaitanya , Patil Sudhir , Patil Ganesh
Published: January 2024

The focus on driver and occupant safety as well as comfort is increasing rapidly while designing commercial vehicles in India. Improvements in the road network have enhanced road transport for commercial vehicles. Apart from the cost of operation and fuel economy, the commercial vehicles must deliver goods within stipulated time. These factors resulted in higher speed of operation for commercial vehicles. The design should not compromise the safety of the vehicle at these higher speeds of operation. The vehicle should obey the driver’s intended direction at all speeds and the response of the vehicle to driver input must be predictable without much larger surprises which can lead to accidents. The commercial vehicles are designed with rigid axle and RCB type steering system. This suspension and steering design combination introduce steering errors when vehicle travel over bump, braked and while cornering. The errors are well known as bump steer, brake steer and roll steer respectively and can cause the unintended vehicle directional response. This work shows the methodology to optimize the steering system design to reduce the steering errors at minimum level as well predictable in nature.

The methodology includes use of newly developed test rig to get the trace of draglink to steering arm ball joint under bump as well as braking conditions. The multibody dynamics model of steering-suspension assembly prepared in MSC ADAMS is validated with test rig results to rightly represent steering system kinematics and compliance. This validated model is then used with novel methodology to get steering hard points which will result in minimum steering errors that are easy for the driver to predict and control the vehicle during high-speed operations. The results obtained from this methodology is further validated with vehicle level result and it is found that this methodology helps to improve the accuracy of prediction for the dynamic behavior of vehicle during braking such as brake pull/steer.
Duty Cycle Based Fuel Consumption Calculation Using Simulation Methodology for Agricultural Tractor
Authors: Gijare Sumant , Karthick K , Juttu Simhachalam , Thipse Sukrut S , Paulraj Lemuel Srinivasan , B Jaiganesh , T Senthil Kumar , Sridharan Sudarsanam
Published: January 2024

This project was undertaken with an objective to develop methodology by formulating set of procedures that would help in achieving the end goal. Once methodology is established, it paves way to optimize the end results more effectively which results in reduced lead time during product development. Methodology can either be based on pure experimental investigations or by simulations. Combination of mathematical and empirical approach is inherently followed in simulations, which helps in reducing the testing time and overall cost.

Commercial vehicles (CV) have seen paradigm shift in the fuel consumption (FC) certification approaches, with an intention to align with 2016 Paris climate agreement. Use of simulation tool like VECTO for commercial vehicle FC certification has gained momentum in Europe. Overall experience gained in commercial vehicle FC simulation has motivated us to leverage the learnings for off-road applications like agricultural tractors. Tractors largely differ from CVs in terms of architecture, duty cycle & overall vehicle resistance. The overall tractive effort for tractors depends significantly on tire-soil & implement-soil interactions. This paper covers all the possible spectrum on the impact of FC through simulation.

The work illustrated here, involves strenuous component level test for engine and complete driveline unit. To begin with, ploughing operation was selected for validation of simulation methodology. Duty cycle data acquired during ploughing comprises for engine operating zones, vehicle velocity, temperatures & instantaneous FC. Data recorded during these test activities along with tractor & implement specifications were used to build simulation model in AVL-VSM. All the effects of tire-soil interaction, plough design parameters & soil properties were studied and validation was established between testing and simulation FC.

For the same velocity profile & plough design the simulation model can be further extended to predict FC for different soil properties.
A Comparative Study of Methanol-Gasoline Blends on Performance and Emissions on BS-IV and BS-VI Class of Two Wheeler Vehicles
Authors: Teja Ravi , Khandai Chinmayananda , Muralidharan M
Published: January 2024

Methanol, a fuel obtainable through the capture and conversion of Carbon Dioxide (CO2), has garnered attention as a suitable alternative fuel for gasoline. Methanol-gasoline blends, characterized by their high-octane rating, commendable performance, and reduced carbon emissions, present themselves as promising alternative fuels for internal combustion engines. In the present study, a comprehensive comparative analysis was conducted to assess the performance and emissions characteristics of unmodified vehicles utilizing methanol blends at lower concentrations, ranging up to 30%, in gasoline. The research focused on two distinct classes of vehicles commonly found on the roads of India: those compliant with BS-IV (Euro IV) and BS-VI (Euro VI) emission standards. Experimental evaluations were carried out on a chassis dynamometer, with the vehicles subjected to the Worldwide Harmonized Motorcycle Test Cycle (WMTC) and Wide open throttle (WOT) driving tests. The emissions from these vehicles were meticulously collected and subjected to detailed analysis to assess the key performance and emission parameters. It was observed that the methanol blends are suitable for BS-IV vehicles without any modifications; however, the BS-VI vehicles need the ECU models to be recalibrated for their adoption of methanol blends.
Methodology for Calculating Use-Phase Emissions for eMobility Subsystem Products
Authors: Singh Mayank Kumar , Sharma Sumit , Pavnaskar Vishwesh , Chakravarty Bithika , Surase Nilesh
Published: January 2024

Battery Electric Vehicles (BEV) are a well-recognized de-carbonization lever that is expected to capture about 15% of road vehicle fleet by 2030 [1, 2]. A large number of organizations are committing to science-based targets (SBTi) and are following roadmap strategies towards Greenhouse Gas (GHG) reduction including all value chain players such as material suppliers, component manufacturers and OEMs [3]. In BEVs, several components are involved in energy transformation and delivery. These components themselves consume energy, and therefore are a cause of GHG emissions during their use. To quantify their contributions and help corporations progress towards decarbonization strategies there is a need for robust use phase calculation methodology. Existing global methods for calculating use phase emissions, such as Green House Gas (GHG) Protocol (version 1.0), provide a good framework, but still have uncertainties in its practical application.

This paper attempts to bridge that gap and present a framework for calculating product use-phase emissions from components in a typical BEV. The use-phase emissions comprise of direct emissions (product's actual energy consumption and energy losses) & indirect emissions (mass-induced emissions). The direct emissions are calculated by segmenting the product functions into drive modes, regeneration, charging, parking, etc. and determining energy loss for each stage. The product power loss testing data is incorporated into a Worldwide harmonized Light duty Test Cycle (WLTC) to simulate standardized driving conditions [4]. The calculated energy loss is adjusted with upstream component efficiencies. The loss calculations from one WLTC cycle are extrapolated across the product’s service life for total operational energy loss from product. The mass-induced indirect emissions are calculated by the concept of Energy Reduction Value (ERV) through powertrain simulation model involving driving and powertrain physics with various vehicle parameters considered [5]. Service life energy consumption from the product is multiplied with region specific emission factor to give the total use-phase emissions.

The methodology has been applied successfully to Eaton’s eMobility portfolio of products and is replicable for any electrical mobility subsystem. It also provides insights on design levers that can improve the GHG performance of the vehicle holistically.
Anti- Rollback Function for Electric Vehicles without HSA/ABS System
Authors: Ganguly Sutanu , Amancharla Naga Chaithanya , Sharma Santosh , Shukla Amisha , Singh Upendra , Abhirag Abhirag
Published: January 2024

In high-end commercial vehicles, technologies like Electronic Braking Systems (EBS) help pull away the vehicle from a standstill on steep gradients with no risk of rolling back. Tata Motors has developed an indigenous Anti-Roll Back (ARB) system that effectively minimizes this risk but without the use of EBS/HSA. The ARB delivers identical functionality to the HSA feature in the EBS but autonomously, and by purely electric means. In the proposed system, the electric traction motor develops a high positive torque when the vehicle tries to roll back upon minimal accelerator pedal press. The system is autonomous in the sense that the driver does not need to press any HSA switch on the dashboard and the system works on relatively flatter road also which otherwise is not the case with HSA as it negatively affects the operation on flatter road by locking wheels and vehicle launches with a very high torque when brakes are automatically released by EBS upon threshold torque build-up. The launch issue of the vehicle with/without HSA switch on low-grade road profile is also taken care by the proposed solution.
ISO 26262 Functional Safety – An Approach for Compliance Readiness
Authors: PATHAK ISHA , Kothari Bhushan
Published: January 2024

Electrical and Electronic systems in a vehicle are increasing manifolds with Electric and ADAS Vehicles taking the lead. There is a rapid transition happening from hardware driven vehicles to software driven vehicles. ISO 26262 is a global standard defined for functional safety (FuSa) in the automotive industry which addresses the structured design and development approach for eliminating electrical malfunctions leading to critical hazards such as fire in EVs. The standard defines specific requirements that need to be met by the safety relevant electrical system and also by development processes. Though the implementation of FuSa is crucial from vehicle safety point of view, its compliance is still a challenge majorly due to lack of awareness, in-built complexities, increase in project development time and subsequent cost.

In this work, we focus on a FuSa implementation model taking into account the conventional new program development cycle. FuSa deliverables are integrated and mapped against the development lifecycle to ensure parallel activities. A strategy is defined to constitute a diversified team with the relevant stakeholders. The paper defines the flow of events and the pre-requisites which are elemental for FuSa compliance. HARA based ASIL target is assessed for meeting the requirements through a structured approach with gateway wise deliverable obedience. Digitalization is ensured by using a tool for mapping the requirements against the subsystem and subsequent test cases along with acceptance criteria. Traceability of the requirements and related deliverables are tracked and documented for the final assessment.

FuSa compliance is very much dependent upon the organization specific goals and priorities. This structured approach can assist in transforming the ‘need’ for compliance into ‘actual’ compliance overcoming the challenges and hurdles. The study also instates that on-boarding of the relevant supplier team in case of distributed development is imperative to achieve the system level FuSa compliance.
Adaptive Derating Algorithm for EV Application Based-Li-Ion Battery for Safe and Healthy Operation
Authors: Gautam Ashish , SJ Janarthanan , Badiger Kartik , Soni Lokesh
Published: January 2024

Battery packs used in Electric Vehicles (EVs) pose significant safety risks and can incur additional costs and downtime when facing extreme conditions such as thermal and undervoltage hard cut-off. This article emphasizes the importance of implementing thermal and voltage based derating techniques to ensure the safe operation of battery packs. Thermal derating controls the maximum allowed battery current to prevent thermal runaway along with maintaining the health of the cells. While voltage derating prevents cut-off at low SOC regions by managing the cell voltage operating range through real time calculation of DCIR based voltage drop. By adopting these methods, battery packs can operate more safely and reliably in various environment conditions, which is essential in many applications.

The article introduces the adaptive derating index, which utilizes State of Health (SoH) and real-time measurements of battery parameters such as temperature, voltage drop, and current to adjust the derating levels accurately. This approach provides more efficient and precise control over battery operation, particularly in dynamic conditions. Derating through battery current is seamlessly done to make sure rider does not feel sudden drop/jerk in power delivery. This algorithm is developed in Matlab/Simulink environment which has properly correlated model wrt real system. The same is then tested and validated in real vehicle. By incorporating the adaptive derating index, battery packs can operate at their optimal levels while maintaining their safety and reliability.
Study of Derived Battery Features for Real-Time Estimation of SOH and RUL of EV Battery Using Data Analysis
Authors: Nangare Kapilraj , Nidubrolu Kranthi , Gaikwad Pooja
Published: January 2024

EVs are extensively utilised with lithium-ion batteries. Predicting the SOH of batteries is desired to achieve optimal operation and health management. The most significant obstacle to accurately predicting battery health is choosing battery features. This study introduces numerous data analysis strategies to manage feature irrelevancy and help determine which features can be selected and used in real-time and edge computing. The first step in manually crafting features is to analyse the evolution pattern of numerous essential battery characteristics. Second, the correlation between selected features and degraded capacity was analysed. Then, selected features are fed into a representative machine learning regression model to effectively predict the remaining capacity of the battery to find the SOH status. Finally, the remaining battery capacity is selected as a feature to predict the RUL in terms of remaining charge-discharge cycles.
Optimizing Closed Loop Air Mass Control in Naturally Aspirated Engines: A Differential Pressure Sensor Approach to Meet BS6 Emission Norms
Authors: Y Pavan , Shanmugam Balaji , R Rachana
Published: January 2024

In order to meet future emission targets and to achieve better fuel efficiency, closed loop air mass control strategies have become essential across all vehicle segments. Closed loop airmass control mandates measuring fresh air mass entering the engine combustion chamber. However, in Naturally Aspirated (NA) engines, while measuring airmass using conventional air mass sensors (AMS), heavy pulsations in the Air-intake results in errors which would impact closed loop airmass control and lead to inconsistencies in emissions. To address this issue, we studied different approaches using AMS with Resonator, differential pressure sensor across the intake air filter and Lambda based airmass control. Based on this empirical study we found that modelling air mass with differential pressure sensor (Delta-P) using Bernoulli’s principle (Flow rate ∝ √Differential pressure) results in higher accuracies compared to conventional methods. This solution gives accurate, cost-effective Air mass modelling in single or two cylinder naturally aspirated engines which are prevalent in Light Commercial Vehicle (LCV) segment for BS6 market. The research provides a detailed explanation of the Air mass modeling approach using Delta-P sensor across Intake Air-filter and its implementation, along with the issues and mitigation measures involved.
Experimental Emission Characteristics Study of Ethanol-Gasoline Fuel Blends on a GDI Engine with a Three-Way Catalyst
Authors: R Navaneetha Kannan , S Easwar Ram , S Satish  Kumar , Karthi Ramanathan , Ramakrishnan Muthu
Published: January 2024

Ethanol-gasoline blended fuels have been widely implemented in Indian markets followed by the Govt of India’s road map as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, effects of Ethanol Blending on engine out emissions characteristics including particulates from gasoline direct injection (GDI) engine remains under development and investigation.

In this study the effect of ethanol blended gasoline fuels with two blending rates 10% and 20% (v/v %) on catalyst conversion efficiencies and emissions on a 1.2 litre 3-cylinder turbo GDI engine is investigated. The addition of ethanol to gasoline fuel enhances the Octane rating (RON) of the blended fuels, oxygen content and changes Reid vapor pressure (RVP). The influence of lambda biasing, and lambda trim controller has been tested. The approach for calibration was adopted based on achieving the target pollutant conversion efficiencies.

Test bench results indicated that with E10 blend all pollutant conversion is more than 98% at all engine operating points. However, with E20 blend using the same lambda bias, fuel enrichment was required to retrieve the NOX conversion efficiency, which was improved back to 98% via suitable trim controller correction.
THC Emission Optimization for Motorcycle Engine by Injector SMD and Spray Angle
Authors: Agrawal Rahul , Kumar Alok , Kumar Vipul , Limje Aniket
Published: January 2024

Emission norms are getting stringent day by day in automotive industry. To meet the rigorous regulation technological advancement is happening across the automotive industry, including two wheeler industry. With the institution of BS6 emission norms, FI system is introduced in two wheeler industry and injectors are intrinsic and most important component of FI system. SMD and spray angle are few of the most important parameters of injector characteristic. In this study the impact of variation of injector SMD and spray angle is studied on engine out emission from small motorcycle engines fitted with port fuel injection system. Impact of injector SMD on cold phase and hot phases of emission cycle (WMTC) is shown with various injector samples with different SMD values. First three THC emission peaks are studied in the cold phase and effect of injector SMD is stated. Apart of injector SMD for small motorcycle engines with port fuel injection, spray angles also play very critical role in engine out emission due to wall wetting effect. Further in this research the impact of injector spray angle is studied in the engine out emission, both with dummy cat-con (without catalyst loading) and loaded cat-con. Influence of injector spray angle is stated in this paper mainly for cold phase of WMTC emission cycle. Finally based on the research, experimentation and experience recommendation is given for injector selection to have better emission characteristic to meet BS6 emission norms for small motorcycle engines. To conclude, for the small engine applications injector with lower SMD and lower cone angle is preferred for emission control.
Data Driven Decisions to Calculate CO
2
Emission for Materials Derived from Estimated Vehicle Weight
Authors: Majumder Kuntal , Pundir Manish , Pathak Arindam , Kumar Rahul
Published: January 2024

This paper discusses the significant impact of changes in a car's gross weight due to various factors such as special accessories, parts, and materials, and how these changes can affect the car's CO2 emissions. Changes in the gross weight of a car can have a profound influence on its environmental footprint, particularly in terms of carbon dioxide (CO2) emissions. This is because the weight of the vehicle directly affects its fuel efficiency and overall environmental performance. The paper highlights that within each carline, there are multiple variants offered to customers, and these variants come with distinct combinations of parts and accessories, adding to the customization options. To accurately determine the CO2 emissions for each variant, it's essential to have a predictive system in place to estimate the gross weight of the cars. To achieve this, the paper suggests using historical data related to the weight of each part used in manufacturing the cars. By leveraging this historical information, it becomes possible to predict the estimated gross weight of a car for any given combination of parts and accessories. This predicted weight can then be employed to calculate the estimated CO2 emissions accurately. In summary, the paper underscores the need for a systematic approach to assessing the environmental impact of cars, considering the influence of part combinations and their associated weights on the overall emissions profile.
“Impact of Design Principles on End-of-Life and Recycling”
Authors: Ali Rifat Fahmida , Harel Samarth , Shaikh Taha , Chakraborty Pinka
Published: January 2024

Automotive industry is a major contributor to global carbon dioxide (CO2) emissions and waste generation. Not only do vehicles produce emissions during usage, but they also generate emissions during production phase and end of life disposal. There is an urgent need to address sustainability and circularity issues in this sector. This paper explores how circularity and CO2 reduction principles can be applied to design and production of automotive parts, with the aim of reducing the environmental impact of these components throughout their life cycle. Also, this paper highlights the impact of design principles on End-of-Life Management of vehicles. As Design decisions of Component impacts up to 80% of emissions [1], it is important to focus on this phase for major contribution in reduction of emissions. Various factors such as material selection, quantity and weight of materials used in parts, design for durability, aerodynamic characteristics, design strategies, design for recycling, and compatibility of assembly processes contribute to such emissions. Research examines the feasibility of using recycled or bio-based plastics, improving part durability, design for disassembly and end-of-life recycling, and minimizing CO2 emissions in the process. Research also highlights challenges for using such material and recommended solutions. Intended Research emphasizes on use of tools like LCA (Life Cycle Assessment) analysis, QDCFS decision matrix, FMEA to find the areas of improvement, to make Product more sustainable and hence improving its End-of-Life Management. Part of the research also highlights data showing the use of recycled content in material and subsequent emission and End of Life impact. Additionally, this thesis investigates different ways of circular Economy Concept and CO2 reduction strategies in automotive industry. The results of this study can provide valuable insights to automotive manufacturers and policymakers to create more sustainable and resilient transportation systems.
Application of Coated Metallic Bipolar Plate for Proton Exchange Membrane (PEM) Fuel Cell
Authors: Sheikh Shabbir , Reum Mathias , Wegener Moritz , Bagcivan Nazlim , Weber Joachim , Schulz Edgar , Stumpf Jan Martin
Published: January 2024

In the current era of green energy adoption for reaching the zero-carbon target, the mobility sector is extensively working together to use hydrogen as a major source of energy, especially in vehicles with long range requirements. For this, Proton Exchange Membrane Fuel Cells (PEMFC) are employed to convert the chemical energy of hydrogen back into electricity. Acceptability of PEMFC in the automotive field mostly depends on system efficiency, durability & cost of the FC stack. In PEMFC, the bipolar plate (BPP) is a critical component of the system, which realizes the transport of gases to the electrodes, evacuates reactant product water and ensures electrical current collection. In some applications, graphite is used as material for bipolar plates due to good chemical stability and corrosion resistance, whereas it is also a rather brittle material with some manufacturing challenges. In mobile applications, metallic bipolar plates are widely used, as they allow for a significantly higher power density of the stack and have good mechanical strength & electric conductivity. Metallic bipolar plates usually feature a protective coating to improve the durability of the system. In this paper, the role of bipolar plates is discussed, and different coating materials are evaluated for performance & cost. An in-house testing strategy is defined to validate coated metallic bipolar plates, which are tested under various operating conditions. Subsequently, test results are discussed to check the improvement of using noble metal free material over available PGM (Platinum Group Metal) coating materials.
Importance of Casting Soundness in Aluminium Parts for Laser Weld Quality
Authors: Umasankar Maiyarasan , Venugopal Sivakumar , Gopalan Vijaysankar
Published: January 2024

Light weight and Robust manufacturing technologies are always needed for transformation drive in the Automotive industry for the next-generation vehicles with greater Power to weight ratio. Innovations and process developments in materials and manufacturing processes are key to this light weighting transformation. Aluminium material has been widely used for these light weighting opportunities. However, aluminum joining techniques, characterized by their poor quality and consistency are limiting this transformation. This technical paper represents one of such case, where the part is made up of Aluminium through conventional casting route which has affected the laser weld quality due to poor casting soundness. This experiment explains in detail about the importance of Casting soundness for laser weld quality, weld penetration, strength etc., and the Product consistency. Casting soundness improvement explored with the support of Ingot quality, Die design, Gating design & Size, Overflow designs, Air vent provisions, Vacuum system etc., through Simulation and Developments. This technical paper will support for knowledge enhancement on casting soundness and process robustness importance towards weld quality.
NVH Refinement of Structure-Borne Tonal Noise in Electric Vehicle
Authors: S Nataraja Moorthy , Rao Manchi , Raghavendran Prasath , Selvam Ebinezer
Published: January 2024

Globally all OEMs are moving towards electric vehicle to reduce emission and fuel cost. Customers expect highest level of refinement and sophistication in electric vehicle. At present, the customers are sensitive to high pitched tonal noise produced by electric powertrain which gives a lot of challenges to NVH engineers to arrive at a cost-effective solution in less span of time.

Higher structure borne tonal noise is perceived in electric vehicle at the vehicle speeds of ~ 28 kmph, 45 kmph and 85 kmph. The test vehicle is front wheel drive compact SUV powered by motor in the front. The electric drive unit is connected to cradle and subframe with help of three mounts. Transfer path analysis (TPA) using blocked forces method is carried out to identify the exact forces of the electric drive unit entering the mounts. Powertrain mount is characterized by applying the predicted forces and dynamic stiffness at problematic frequency is measured. By reducing the dynamic stiffness of powertrain mounts, the noise levels are reduced by ~ 5 dB (A). The dynamic stiffness at powertrain mount connection point on cradle and subframe is increased by ~ 2 times which reduced noise by ~ 3 dB (A). With all the modifications, noise levels are considerably reduced by ~ 10 dB (A). NVH criteria which should be considered to avoid the structure borne tonal noise is also elaborated.
Systematic Approach to Mitigate Urea Tank Sloshing Noise in Passenger Vehicles
Authors: S Tharakeswarulu , S Nataraja Moorthy , Rao Manchi , Raghavendran Prasath
Published: January 2024

In the current era, vehicle manufacturers focus has increased towards passenger comfort and one of the key areas is NVH. Vehicle level NVH targets are cascaded to component level for obtaining better refinement in cabin. One such performance attribute is sloshing noise of urea in diesel vehicles. Migration from BS4 to BS6.2 norms demand complex technological changes to automobile manufacturers to add extra components to the vehicles which is a big challenge in identifying the locations at critical stage of the project phase. In one of the developments of mid SUV category vehicle, sloshing noise from urea tank is perceived as objectionable during low-speed braking and while passing over speed breakers.

This paper addresses the measurement conditions of sloshing noise and its evaluation procedure to quantify the sloshing noise at vehicle level. The sloshing noise is perceived in the frequency band of 50 to 1000 Hz. This paper also shows road map to reduce sloshing noise at source level by various methods. Fluid flow pattern studies are carried out to identify appropriate location to place baffles inside the tank. Different profiles like straight, inclined, and curved baffles performance contribution is assessed to reduce the level of sloshing noise.

This paper also cites about different design of experiments conducted to reduce structure borne as well as air borne-noise contributions originating from urea tank. The structure borne noise till 350 Hz is reduced by increasing structural stiffness at tank attachment locations and through bush stiffness reduction which reduced the dynamic forces entering the tank. Damping pads are applied over the tank to reduce the noise radiation. Air borne noise contribution to sloshing noise in the band 400 to 1000Hz is reduced by using acoustic package cover over the tank. With all above modifications, the sloshing noise level is reduced by ~5 dB(A) and is acceptable.
Design Optimization of Engine Mount Bracket to Reduce Various Gear Noises in the Passenger Car Cabin
Authors: Ghosh Chiranjit , Agrawal Adheesh , Karmakar Sudipto , Srivastava Shubham , Khan Aamir
Published: January 2024

With the advancement of regulatory norms in automobile industry, there is a challenge to meet performance efficiency targets, especially with a lightweight platform, while providing superior driving experience to customers. The shift towards weight optimization, makes the vehicle structure more susceptible to transfer a diverse range of noise and vibrations through body.

Although most undesirable noises perceived inside the cabin can be reduced by superior technology engine mounts and NVH packaging, all such solutions lead to cost addition. Intelligent considerations in part design can be used to supplement predictable transfer paths to quell the unwanted vibrations.

One such case is of the gear whine noise in certain rpm bands caused by inherent gear meshing frequency coinciding with natural frequency of an engine mounting bracket. This paper demonstrates two methodologies to counter such a phenomenon, either through engine mount bracket natural frequency optimization or addition of a dynamic damper. However, the focus is on frequency and mobility optimization approach. Another case is of gear “JAA” noise originating from the rattling of remaining freely engaged gears. This kind of gear induced vibration tends to transfer along dynamically weaker structural parts and become audible inside the cabin. This is countered by reducing the mobility of transfer path viz. engine mounting brackets.
Noise Reduction on Electric Two-Wheeler by Structural Modification and Gear Design Optimization
Authors: Chivate Shriniwas Dilip , Gaikwad Atul Annasaheb , Taware Ganesh Nanasaheb , Walke Nagesh
Published: January 2024

The low running cost of electric two wheelers is resulting in high popularity and growing market share. The electric two wheelers are generally considered silent. However, the tonal nature of radiated noise is annoying for both driver and pedestrians in electric vehicles. This study focuses on electric two-wheeler with annoyance issue. The customer complained about non-linear noise with respect to speed and also whining during loading and coasting. The detailed Noise Source Identification (NSI) revealed that the noise is due to motor and transmission whine and structural resonances of chassis excited by this motor excitation during runup and gear whine orders during coasting when excitation by motor is absent. The motor mounting and chassis are structurally modified with suitable stiffeners and damping based on the results of modal analysis. The transmission gear geometry and contact pattern are optimized for transmission error reduction. The modification resulted in 6-8 dB overall noise reduction with complete elimination of whine noise in loading as well as coasting operation.
Analysis and Mitigation of Grunt Noise in Hydraulic Power Assisted Steering Systems
Authors: Sethi Ajitesh , Titave Uttam , Vardhanan K Aravindha Vishnu , Zalaki Nitin , Naidu Sudhakara , Salunkhe Swapnil
Published: January 2024

This paper addresses the "Grunt Noise" anomaly in Hydraulic Power Assisted Steering (HPAS) systems, detailing an extensive effort to resolve this disruptive issue. HPAS, while cost-efficient, faces challenges as it adapts to customer demands for reduced steering effort and enhanced handling. Intensified HPAS intervention requires components to withstand higher pressures and tighter tolerances, leading to occasional anomalies.

"Grunt Noise" arises from Torsion bar (T-bar) resonance with fluid pressure pulsations. A comprehensive study identifies load conditions, transfer paths, and frequency bands, extending from vehicle to Pinion Valve assembly levels. Root cause analysis traces the issue from Steering Wheel to T-bar, validating the approach. The T-bar's twisting operation renders torsional stiffness crucial for Grunt Noise. Lower stiffness T-bar, when overpowered by liquid force, causes microsecond imprecise valve openings, leading to cavitation-induced Rack & Pinion vibrations. Varying T-bar stiffness (via diameter alteration) is assessed to minimize variability.

By enhancing T-bar's torsional stiffness and dimensions, the study effectively mitigates Grunt Noise in HPAS systems. In summary, this paper offers a thorough HPAS Grunt Noise analysis, emphasizing the pivotal role of torsional stiffness in resolution.
Powertrain Mounting System NVH Simulation Methodology Using Transfer Path Analysis Technique for Electric Vehicles
Authors: Duraikannu Dinesh , Iqbal Shoaib
Published: January 2024

In comparison to traditional gasoline-powered vehicles, Electric vehicles (EVs) development and adoption is driven by several factors such as zero emissions, higher performance, cost effective in maintenance, smoother and quieter ride. Global OEMs are competing to provide a reduced in-cab noise for ensuring a smooth and quiet driving experience. Short project timelines for EV demands quick design and development. In initial stages of project, input data availability of EV is limited and a simplified approach is necessary to accelerate the development of vehicle. This paper focuses on simulation methodology for predicting structure borne noise from powertrain deploying Transfer Path Analysis approach. Current simulation methodology involves full vehicle model with multiple flexible bodies and full BIW flexible model which leads to complex modelling and longer simulation times.

The proposed transfer path analysis technique utilises, a simplified Multibody Dynamics EV powertrain mount model and EV Motor Model considering Electromagnetic Forces with 24 DOF for Peak and Continuous torque for predicting mount forces, and a simulated or measured Noise Transfer Functions (NTFs) and Vibration Transfer Functions (VTFs) to predict noise. This method provides the same results as existing methodology but with a reduction of 80% in overall time. This novel methodology helps in design optimization of EV Powertrain mounts' configuration for reduced noise levels by identifying the individual mounts' contribution to noise.

The proposed transfer path methodology is observed to have better correlation with physical measured data of above 90% and it has advantage in terms of simpler modelling approach, faster simulation and accurate results. This methodology could be helpful for the powertrain mounting system configuration for the entire design community.
A Simulation Methodology to Design the AVAS System to Meet Safety Regulations and Create the Expected Perception for the Vulnerable Road User
Authors: Calloni Massimiliano , Hadjit Rabah , Salvekar Pinak , Musser Chadwyck
Published: January 2024

Designing an effective AVAS system, not only to meet safety regulations, but also to create the expected perception for the vulnerable road user, relies on knowledge of the acoustic transfer function between the sound actuator and the receiver. It is preferable that the acoustic transfer function be as constant as possible to allow transferring the sound designed by the car OEM to ensure the safety of vulnerable road users while conveying the proper brand image. In this paper three different methodologies for the acoustic transfer function calculations are presented and compared in terms of accuracy and calculation time: classic Boundary Element method, H-Matrix BEM accelerated method and Ray tracing method. An example of binaural listening experience at different certification positions in the modeled simulated space is also presented.
Multiphysics Simulation Supporting Systems Engineering for Fuel Cell Vehicles
Authors: Tatschl Reinhard , Poetsch Christoph , Reiter Anton , Ritzberger Daniel
Published: January 2024

Legislative challenges, changing customer needs and the opportunities opened-up by electrification are the major driving forces in today’s automotive industry. Fuel cell vehicles offer the potential for CO2 emission free mobility, especially attractive for heavy duty long-haul range application. The development of key components of fuel cell powered vehicles, namely the fuel cell stack itself as well as the related hydrogen/air supply and thermal management sub-systems, goes hand in hand with various challenges regarding performance, lifetime and safety. The proper layout and sizing of the stack and the related fuel and air supply system components, as well as the suitable dimensioning of the cooling system, are decisive for the overall system efficiency and achievable lifetime. Finally, the different components and sub-systems need to be integrated into the overall powertrain and vehicle configuration together with the related control functions to ensure proper operation under all driving scenarios and ambient conditions. In the above context, system simulation enables to support the development teams in the different phases of the development process, from concept layout, to detailed component and sub-system development to virtual integration and calibration. The current work presents such a versatile multi-physics simulation methodology and provides insights into the modelling fundamentals regarding the various components and subsystems adopted. To confirm the validity of the underlying modelling, comparisons of simulation results with corresponding experimental data are presented for selected fuel cell system components and operating conditions. The applicability of the overall simulation framework to support the development and optimization of fuel cell systems is demonstrated for selected use-cases.
CAE Based Benchmarking of Shaft Deflection for Transmission Gear Rattle Noise
Authors: Bijwe Vilas B. , Kulkarni Shriram , Vaidya Rohit , Shah Bhartendra
Published: January 2024

Vehicle transmission gear rattle is one of the most critical NVH irritants for refined vehicles. It is perceived more dominantly in lower gears of vehicle running. It depends on various design parameters like engine input torque amplitude & fluctuations, driveline torsional vibrations, gear micro & macro geometry, shaft flexibility, etc. Establishing exact contribution of each of these parameters to transmission rattle, thru experimental or simulation technique, is very challenging. Current paper explains the NVH CAE benchmark approach deployed to understand difference in rattle behavior of two transmission designs. Paper focuses on simulation of gear impact power and its sensitivity to transmission shaft deflections. Impact power is one of the indicators of transmission rattle noise and transmission shaft deflection is one of the contributors for gear impact power. 3D MBD simulations are carried out to calculate loose gear impact power by applying angular acceleration input to transmission input shaft. Gear impact power results corroborate the perceived rattle behavior of two designs of transmission. For shaft flexibility, FEA based nonlinear static simulations are carried out to calculate shaft deflections by applying torque induced forces at each of the gear contacts for a given gear engaged condition. Shaft deflection results of two transmission designs, under identical loading and boundary conditions, indicate the contribution of shaft flexibility towards difference in gear impact power. Transmission design feature causing this difference in shaft deflection is identified and its sensitivity towards rattle is established.