Browse Topic: Engine mounts

Items (680)
Diesel powertrains are inherently characterized by high vibration levels and low-frequency excitations, which are extremely demanding for passenger comfort and vehicle refinement. Conventional passive engine mounts often fall short in mitigating such vibrations effectively across a wide range of operating conditions. Passive mounts are inadequate for effectively isolating vibrations in powerful, lightweight vehicles or those without a balancer shaft 3-cylinder engine ordiesel engines. Consequently, this has prompted the consideration of active engine mounts as an alternative solution for solving NVH (Noise, Vibration, Harshness)-related issues. This paper explores the application of adaptive control algorithms in active engine mount systems for diesel powertrains in passenger vehicles. Through the integration of real-time feedback loops with smart control strategies the system adaptively controls mount stiffness and damping to minimize engine-induced vibrations. The study presents
Hazra, SandipKhan, Arkadip Amitavamore, Vishwas
The evolution of electric vehicles (EVs) also demands the evolution of powertrain mounting systems to achieve superior Noise, Vibration, and Harshness (NVH) performance. This study presents a comparative evaluation of cradle, saddle and ladder mounting systems in EV applications. Examples of experimental modal analysis and vehicle-level vibration tests were performed in order to evaluate structure-borne noise transmission as well as airborne noise transfer under operating conditions. Important parameters like mount stiffness, isolation efficiency and dynamic load distribution were performed. These findings provide valuable guidance for selecting optimal mount strategies to enhance occupant comfort and acoustic quality in future EV designs. Recommendations for mount system improvements considering evolving EV architectures are also discussed. This work provides a crucial, experimentally-validated framework for selecting optimal mounting architectures, addressing a key gap in the
Hazra, Sandipmore, VishwasNaik, Sarang Pramod
The increasing adoption of electric vehicles (EVs) has intensified the demand for advanced elastomeric materials capable of meeting stringent noise, vibration and harshness (NVH) requirements. Unlike internal combustion engine (ICE) vehicles, EVs lack traditional masking noise generated by the powertrain. In the automotive industry, the dynamic stiffness of elastomers in internal combustion engines has traditionally been determined using hydraulic test rigs, with test frequencies limited to a maximum of 1,000 Hz. Measurements above this frequency range have not been possible and are conducted only through computerized FE or CAE calculation models. Electric drive systems, however, generate distinct tonal noise components in the high-frequency range up to 10,000 Hz, which are clearly perceptible even at low sound pressure levels. Consequently, the dynamic stiffness characteristics of elastomers up to 3,000 Hz are critical for optimizing NVH performance in EVs. This study focuses on high
Bohne, ChristianGröne, Michael
Engine mount brackets are a primary structural components of passenger vehicles that supports the powertrain to the chassis via engine mounts. These brackets are important to control vibrations and the transmission of noise into the cabin as well as vehicle stability. Since they support the engine mounts, these brackets play a role in determining ride comfort and load distribution on the mounts and the engine. While traditionally made from steel, cast iron and aluminum, we are trying to redesign engine mount brackets with recyclable engineering plastics to fit current demands of light-weighting, cost efficiency, and sustainability. The present work is concerned with the design of a plastic engine mount bracket, which aims to hit specified natural frequency targets in order to avoid resonance and fulfill strict NVH (Noise, Vibration, and Harshness) requirements. Because of the superior mechanical strength, thermal stability, and vibration-dampening properties, PPS, glass-fiber
Hazra, SandipGupta, DeepakKhan, ArkadipGite, Yogesh
With growing significance of electric vehicles (EVs), their powertrains – while naturally quieter than internal combustion engine (ICE) powertrains – pose new NVH (Noise, Vibration, Harshness) challenges. These are triggered mainly from high-frequency disturbances caused by electric motors and gear interactions. Isolation of such excitations is essential for securing cabin refinement and customer expectations for acoustic comfort. This paper offers a simulation-based approach to optimal placement of the electric drive unit (EDU), which houses the electric motor and gearbox, with the objective of reducing vibration transfer to the chassis of the vehicle. The methodology explores the effect of spatial mount repositioning under actual dynamic load conditions through multibody dynamics (MBD) modeling and integrated optimizer using advanced multibody dynamics simulation software – Virtual Dynamics. The suggested workflow helps in effective investigation of mount positioning within packaging
Shah, SwapnilMane, PrashantBack, ArthurEmran, Ashraf
This work focuses on the prediction of Trimmed Body Noise Transfer Function (NTF) using Glazed BIW (body in white) structural model characteristics by leveraging Machine Learning (ML) technique. Inputs such as Glazed BIW (GBIW) attachment dynamic stiffness, Body Panel Vibration Transfer Functions (VTF) and Driver Ear level NTFs are employed to predict Trimmed Body NTF for a particular hard point. An iterative process of performing design modifications on the BIW to verify its effect on BIW performance and therefore on Trimmed body NTF is undertaken. BIW geometric parameters are varied in an organized manner to generate hundreds of data points at GBIW level which are provided as input to the train the ML model to predict the trimmed body level NTF. The outcome provides crucial insights of how the trimmed body NTF is closely related to the GBIW design characteristics. This ML approach of predicting trimmed body NTF based on GBIW characteristics provides critical insight about GBIW design
Kulkarni, Prasad RameshBijwe, VilasKulkarni, ShirishSahu, DilipInamdar, Pushpak
In the evolving landscape of the automotive industry, enhancing passenger comfort and ride quality has become a key differentiator for manufacturers. While suspension systems have traditionally received significant attention, powertrain isolation through engine mounts plays an equally critical role in controlling noise, vibration, and harshness (NVH). Engine mounts are not only responsible for supporting the powertrain’s weight but also for mitigating the transmission of unbalanced engine forces to the vehicle body. Modern engine mount designs aim to eliminate any metal-to-metal contact between the powertrain and chassis, thereby achieving optimal vibration isolation. This study proposes a refined approach to completely decouple the powertrain from the vehicle structure, ensuring minimal vibration transfer and thereby extending the operational life and performance of the engine mount system.
Hazra, SandipNaik, Sarang PramodMore, Vishwas
Generally, in an electric sports utility vehicle with rear mounted powertrain the mass distribution is greater in the rear compared to front. This higher rear to front weight distribution results in oversteer behavior during high-speed cornering deteriorating vehicle handling & risking passenger safety. To compensate this inherent oversteer nature of such vehicles & produce understeer behavior, the steering rack is placed frontwards of the front wheel center for toe-out behavior due to lateral compliance during cornering. This compensation measure results in lower Ackermann percentage resulting in higher turning circle diameter deteriorating vehicle maneuverability. This paper proposes a design to obtain ideal understeer gradient with minimal turning circle diameter through utilization of split link technology with a McPherson Strut based suspension framework & frontwards placed steering rack. This suspension is utilized in our Mahindra Inglo platform. This paper elaborates on how
Nadkarni, Ameya RavindraMhatre, NitijPatnala, AvinashNAYAK, Bhargav
Noise, Vibration, and Harshness performance refinement and long-term vehicle reliability are rapidly evolving in today’s automotive industry and becoming a basic need considering comfort. Engine mounts play a central role in isolating powertrain-induced vibrations. Their deterioration can significantly affect cabin comfort, powertrain integrity, and customer satisfaction. Prior work in this area has primarily focused on direct mount sensors and physical inspection at service centre after failure. While effective in controlled environments, such methods are not scalable, add system complexity and increase vehicle cost due to sudden breakdowns. This paper introduces a novel indirect health monitoring method that leverages a driver seat rail-mounted accelerometer to capture driver specific vibrational responses. By analysing these signals using machine-learning models placed by AIML ECU and domain-specific analytical features, engine mount health is inferred without requiring sensors on
Iqbal, ShoaibDusane, Mangesh
The scale of worldwide population presents its own set of difficulties, especially in densely populated cities. Almost every individual has some form of personal transport, which leads to congestion and limited parking space. Automotive manufacturers are scaling down the size of vehicles to resolve these issues to some extent. This paper is based on the NVH development of a single cylinder diesel engine vehicle. It provides an insight into the comprehensive vehicle level NVH refinement approaches adopted. The NVH characteristics of benchmark two-cylinder diesel and baseline vehicle were measured and analyzed for target setting. The performance of each subsystem such as engine mounting, vehicle structure, intake and exhaust was evaluated, and gap analysis was performed against set targets. It was found that the engine mounting system and vehicle structure were inefficient in isolating the excitation forces. The design and location of the mounting system was evaluated using CAE and
Ghale, Guruprasad ChandrashekharBaviskar, ShreyasBendre, ParagKamble, PranitBhangare, AmitTHAKUR, SUNILKunde, SagarWagh, Sachin
Balance towards various Vehicle attributes often faces design contradictions, particularly in Noise, Vibration, and Harshness (NVH) optimization. Traditional approaches rely on trade-offs, but TRIZ (Theory of Inventive Problem Solving) offers a structured methodology to resolve contradictions innovatively. This paper presents TRIZ-based solutions for 2 key NVH challenges: (1) exhaust systems requiring noise reduction while maintaining low engine back-pressure, (2) engine mounts requiring both softness for vibration isolation and hardness for durability & vehicle stability, By applying TRIZ principles such as separation, mechanics change, etc. and using Thinking Tools such as thinking in time & scale, novel solutions are proposed to achieve superior performance without traditional compromises. These case studies demonstrate how TRIZ enhances automotive NVH refinements by enabling systematic innovations. This also explores benefits of Frugal Engineering for profitable launch of new
A, Milind Ambardekar
Hydraulic engine mounts are widely used in automotive applications to reduce vibration and noise transmission from the engine to the vehicle body by providing high damping at low frequencies and low damping/stiffness at higher frequencies. This is achieved by allowing sufficient clearance between components inside the hydro mount, activating hydraulic damping only with sufficient amplitude inputs. However, this inherently leads to the generation of parasitic noises emanating from hydraulic engine mounts which significantly degrade the Noise, Vibration, and Harshness (NVH) performance of vehicles, presenting a considerable challenge in the automotive industry. This encompasses phenomena such as cavitation, arising from the formation and subsequent collapse of vapor bubbles within the working fluid due to localized pressure drops below the vapor pressure, and membrane hitting, resulting from the dynamic interaction between the fluid and the elastic membrane within the mount. Both noise
Agrawal, AdheeshVineeth, SekharanGhosh, ChiranjitSaxena, AkshanshParmar, AashishSeenivasan, GokulramNandal, AbhishekDhankhar, Dinesh SinghKhan, Prasenjit
TOC
Tobolski, Sue
With the rising demand for high performance and reliability in engineering machinery, the vibration isolation performance and robustness of the powertrain mounting system (PMS) have become critical to overall machine performance. However, during service, rubber mounts are prone to environmental influences, causing significant stiffness deviations that render traditional optimization and analysis methods inadequate. To address this, this article proposes an uncertainty optimization strategy combining Monte Carlo and genetic algorithm (MC-GA), applied to design optimization accounting for stiffness uncertainty due to mount aging, to enhance vibration isolation robustness under large-scale stiffness fluctuations. The study first establishes a Monte Carlo analysis framework based on the statistical characteristics of retired mount stiffness and a dynamic model, systematically evaluating the impact of varying stiffness deviations on vibration characteristics under the original PMS
Xiang, XingyuYi, HongweiHou, JiePeng, ChengHuang, HaiboHuang, Xiaorong
The new Stage 5 emission regulation requires several changes on engines as well as design and development of new auxiliary systems. These changes affected the engine dynamics and NVH characteristics. These changes are validated for various operating conditions on engine test cell in a controlled environment where engine is mounted on test cell with dyno. Further, this engine will be used by other machine forms, hence NVH performance needs to be evaluated for all the applications. Isolation of three-cylinder engines is challenging since it has to deal with inherent imbalance forces while providing the isolation to meet the durability requirements of heavy applications from off highway machines. This paper covers the methods used for verification of engine isolation performance. NVH tests are conducted for integration of three-cylinder engine with roadbuilding machine. An analytical model is developed to identify rigid body modes and mount transmissibility. Results from this analytical
Pawar, Sachin M.Mandke, Devendra LaxmikantKASABE, SANDEEPJadhav, Vijay
Engine and powertrain mounts are vital for isolating vibrations and reducing the transmission of Noise, Vibration, and Harshness (NVH) from the engine to the vehicle structure. Despite technological advancements, addressing NVH issues related to tribological factors continues to pose significant challenges in automotive engineering. This study aims to systematically identify and optimize design parameters of engine/powertrain mounts to minimize NVH levels using CAE tools and parametric optimization techniques in Abaqus and Isight, respectively. The purpose of this research is to investigate the correlation between various design parameters of powertrain mounts and their impact on NVH characteristics. Specific attention is focused on noises such as clunking, banging, or thumping that emerge from the engine bay under dynamic conditions like acceleration, braking, or turning. These sounds often occur as the engine moves excessively due to worn mounts, making unintended contact with other
Ganesan, KarthikeyanSeok, Sang Ho
Powertrain mounts are vital for isolating vibrations and enhancing vehicle ride comfort and performance, making their dynamic behavior critical for effective design. This study provides a comprehensive analysis of powertrain mount decoupling by integrating virtual simulations, physical testing, and analytical calculations. In our approach, we first derived stiffness data through analytical calculations, which were validated through multi-body dynamics (MBD) simulations that modeled interactions within the powertrain mounts. By adjusting bush stiffness parameters within the MBD framework, we predicted decoupling frequencies and analyzed kinetic energy distribution. The iterated stiffness values from simulations were then confirmed through physical testing, ensuring consistency in decoupling frequencies and energy distribution. This alignment between virtual and experimental data enhances the reliability of our findings and helps identify overlapping frequencies across vehicle systems
Shende, KalyaniShingavi, ShreyasRane, VisheshHingade, Nikhil
In the development of engine mounting systems for passenger cars, accurately capturing dynamic loads during real-world driving conditions is crucial for optimizing performance, durability, and NVH (Noise, Vibration, and Harshness) characteristics. This paper introduces an innovative approach that integrates load cell and strain gauge technologies for Road Load Data (RLD) acquisition, specifically designed for engine mounting applications. By combining load cells and strain gauges, this method offers a comprehensive solution for measuring both direct forces and the resulting strains on engine mounts, providing a more detailed understanding of the load profiles. Load cells capture the overall forces exerted on the engine mounts, while strategically placed strain gauges measure local deformations and stress distributions within the mounts. This dual-method approach enables precise correlation of force and strain data, enhancing the accuracy of load calculations under various driving
Hazra, SandipKhan, Arkadip AmitavaMohare, Gourishkumar
Platform based vehicle development is standardized at John Deere. The challenges of frontloading the integration of individual components within different platforms using predictive methods is key to shortening the development cycle. Components are individually characterized on test benches and results cannot directly be used to evaluate system performance. Invariant characterization is needed instead, which is possible through techniques such as blocked loads estimation. To evaluate the applicability of such methods, the component-based loads and vehicle in-situ operational loads need to be compared. The confident use of these methods for obtaining structural and acoustic loads enables the use of hybrid system models, enhancing early NVH response predictions. The objective of this work was to enable the confident use of test stand measurements in predictive models across various vehicle platforms. This study compares a powertrain characterization in a vehicle against a test stand to
Vesikar, Prasad BalkrishnaEdgington, JasonDrabison II, John
Electric vehicles (EVs) differ from internal combustion engine (ICE) vehicles in that they lack a conventional engine and feature an electric drive unit, leading to distinct dynamic behaviours in the powertrain. Additionally, the arrangement of auxiliary components in EVs often differs from that in traditional ICE vehicles, which can sometimes significantly impact safety ratings. This paper examines a case study of a critical failure during a crash test, where displacement of an engine mount arm caused substantial structural intrusion and reduced the vehicle’s safety rating. To address this issue and enhance crashworthiness, a “crash plate” was designed and integrated into the mount system. This solution effectively constrained the mount arm’s movement during impact, preventing the intrusion observed in previous tests. The paper provides a detailed analysis of the crash plate’s dimensions and its relationship to the engine mount, demonstrating its potential for broader application in
Hazra, SandipKhan, ArkadipMohare, Gourishkumar
To optimize the noise that heard like ‘kalakala’ produced by the plug hybrid electric vehicle when accelerating with a small accelerated pedal opening while in the charging state of series modal. The LMS test device was used to acquire the noise of the driver's outer ear. Through filtering and playback analysis, it was confirmed that the noise is mainly contains the frequency bands of 250-400Hz and450-700Hz. The frequency bands of the noise were used as carriers for Hilbert transform, and their envelopes were obtained for Fourier transform analysis. It was found that the modulation order of the noise is 0.5 times of the engine ignition order, and the modulation frequency is 20-30Hz, which let the customer hears like roughness. Regarding the spectral characteristics of this noise, firstly, at the excitation source, selected a reasonable moment of inertia and frequency of the Crank torsional damper, to decrease the torsional excitation of the engine. Secondly, investigated the structural
Shouhui, HuangZhongxun, HuZhao, YunShanyin, RenRuifeng, DongTeng, CharlieChangshui, ZhouXu, Ling
High-frequency whine noise in electric vehicles (EVs) is a significant issue that impacts customer perception and alters their overall view of the vehicle. This undesirable acoustic environment arises from the interaction between motor polar resonance and the resonance of the engine mount rubber. To address this challenge, the proposal introduces an innovative approach to predicting and tuning the frequency response by precisely adjusting the shape of rubber flaps, specifically their length and width. The approach includes the cumulation of two solutions: a precise adjustment of rubber flap dimensions and the integration of ML. The ML model is trained on historical data, derived from a mixture of physical testing conducted over the years and CAE simulations, to predict the effects of different flap dimensions on frequency response, providing a data-driven basis for optimization. This predictive capability is further enhanced by a Python program that automates the optimization of flap
Hazra, SandipKhan, Arkadip
In the field of automotive engineering, the performance and longevity of suspension bushings and powertrain mounts are critical. These components must endure fatigue loads characterized by their variable amplitude, multi-axial nature, and out-of-phase oscillations. The challenge lies in comprehensively characterizing these service loads during the early stages of vehicle production to foresee potential issues that may arise during later stages. Additional complexity in this analysis is introduced by the nonlinear hyperelastic deformation exhibited by natural rubber, a common material used in these components. To address these challenges, original equipment manufacturers (OEMs) and suppliers employ Computer-Aided Engineering (CAE) techniques for fatigue life predictions. These predictions are complemented by physical testing involving what are known as block cycles. However, the results obtained from these approaches often fail to fully represent the real loading conditions that a
Zarrin-Ghalami, TouhidDatta, Sandip
A methodology for optimizing natural properties of a powertrain for an electric vehicle has been presented. A model with six-degree-of-freedom was proposed utilizing ADAMS, and the natural frequencies and energy distribution of the powertrain are estimated using the proposed model. The calculated natural frequencies and energy distribution shown that the initial design of mount stiffness does not meet requirements of natural frequency and decoupling ratio, and vibration isolation standards. To overcome the limitations of conventional optimization techniques, a non-dominated sorting genetic algorithm (NSGA) was adopted for the enhancement optimization the mounts parameters. The optimization objectives included the refinement of the decoupling rates and frequency distribution at all mounting directions. Stiffness parameters of the mounts were optimized via the NSGA. The optimized results confirmed significant improvements for powertrain natural characteristics. This study presented an
Jin, YangLi, DeweiZhao, YangXiao, LeiGuo, Yiming
The primary functions of mounts include providing structural support, sound insulation, and vibration damping. Dynamic stiffness and loss angle are critical metrics for evaluating their NVH (Noise, Vibration, and Harshness) performance. This paper examines a floating decoupler hydraulic mount featuring a long decoupler membrane track. A nonlinear lumped parameter model is developed to calculate the dynamic stiffness and loss angle. The model incorporates fluid flow in the lower chamber and variations in the support reaction force of the decoupler membrane under switching conditions. Parameters of the nonlinear lumped parameter model, including rubber stiffness, equivalent piston area, and volumetric compliance of the fluid chamber, were analyzed and calculated using the finite element method. The influence of different decoupler membrane track structures on the frequency corresponding to the minimum high-frequency dynamic stiffness was investigated based on the established model. The
Li, ShenghaoZhang, ShenglanYu, ChaoTu, XiaofengShangguan, Wenbin
Optimizing engine mounting systems is a complex task that requires balancing the isolation of vehicle vibrations with controlling powertrain movement within a limited dynamic envelope. Six Degrees of Freedom (6DOF) optimization is widely used for mounting stiffness and location optimization. This study investigates the application of various optimization algorithms for 6DOF analysis in engine mount design, where the system’s stochastic behaviour and probabilistic characteristics present additional challenges. Selecting an appropriate optimization framework is essential for achieving accurate and efficient NVH results. Recent advancements in research have introduced several 6DOF optimization algorithms to determine the optimal stiffness and location of engine mounts. The study evaluates a range of optimization methods, including Simultaneous Hybrid Exploration that is Robust, Progressive and Adaptive (SHERPA), Quadratic Programming (QP), Genetic Algorithm (GA), Particle Swarm
Hazra, SandipKhan, Arkadip
In the ongoing Road Load Data Acquisition (RLDA) for engine mounts, a load cell arrangement is being utilized, where the load cell must be placed between the mount arm and an engine mount bracket or an additional tower bracket. This configuration required the design of a custom mount arm with a crank in the Z direction, secured with a single bolt to accommodate the load cell. However, this method has revealed significant load coupling in the X and Z directions, resulting in incorrect load prediction for engine mount testing. This happens due to the architectural packaging of the engine mount on the long member to meet NVH requirements. To mitigate these issues, an alternative strain gauge-based RLDA approach was investigated. The optimal locations for strain gauge placement were determined using the inverse matrix method with the assistance of Computer-Aided Engineering (CAE) analysis. Strain gauges were then installed at these identified locations on the mount arm. The engine mount
Hazra, SandipKhan, ArkadipMohare, Gourishkumar
Due to stringent emission norms, all OEMs are shifting focus from Internal combustion engine (ICE) to Electric vehicle (EV). NVH refinement of EVs is challenging due to less background noise in EVs in comparison with ICE vehicles. Motor whine noise is perceived inside cabin till the speed of 20 kmph. Vehicle is powered by electric powertrain (EPT). Electric powertrain is connected to the subframe with the help of three powertrain mounts. Subframe is connected to the body with the help of four mounts. With the help of Transfer Path Analysis (TPA), it is identified that the noise is structure borne and the dominant path is identified. By optimizing the stiffness of the EPT mounts, the structure borne noise levels are reduced. But reducing the stiffness of EPT mount deteriorated the road noise levels. The reason behind deterioration of road noise is investigated. The performance of double isolation of EPT is compared with single isolation of EPT with respect to both road and motor noise
S, Nataraja MoorthyRao, Manchi VenkateswaraRaghavendran, PrasathSelvam, Ebinezer
The stiffness and positioning of engine mounts are crucial in determining the powertrain rigid body modes and kinetic energy distribution. Therefore, optimizing these mounts is essential in the automotive industry to separate the torque roll axis (TRA) and minimize vibration. This study aims to enhance mount locations by isolating the engine rigid body modes and predicting the inter-component force (ICF) and transfer function of the vehicle. The individual ICFs for engine mountings are calculated by applying a unit force at the bearing location. Critical frequencies are identified where the amplification exceeds the unit force at the mounting interface between the engine and the frame. The transfer function approach is utilized to assess the vibration at the handlebar. Both ICF and transfer functions analyze the source and path characteristics linked to critical response frequencies. This understanding aids in enhancing mounting positions to minimize vibration levels, thereby enhancing
Jha, Niraj KumarYeezaku, Antony NeominVictor, Priyanka EstherKrishnamurthy, Govindasamy
The functionality of the Powertrain mount is to securely anchor the engine and gearbox within a vehicle, and effectively absorb vibrations, while simultaneously shielding the vehicle's body from powertrain movements and road irregularities. The mounts are supported by engine mount brackets, which serve as connectors between the engine mount and the vehicle's body-in-white (BIW), providing a structural link that secures the engine and gearbox assembly. Conventionally made with materials such as aluminum, sheet metal, or cast iron, a recent surge has been seen toward using a viable substitute in Fiber Reinforced Polymer (FRP). This transition is driven by the potential to reduce weight and cost, while also improving Noise, Vibration, and Harshness (NVH) characteristics. This study aimed to evaluate the relative strengths of existing brackets compared to those made of FRP, with a focus on their modal response and crash resistance. Due to the absence of a standardized method for modelling
Hazra, SandipKhan, Arkadip
A method of overall modeling and step-by-step solution was proposed to verify and analyze the strength of the mount shell. First, a reliable finite element simulation model was established based on testing of the mechanical properties of rubber materials, constitutive model construction, and stiffness tests of the mounts. Second, the displacement of the mount system under preloading and crash loads was calculated separately through the modeling of the powertrain mount simulation, which provided accurate load conditions of the mount for the following work. Finally, the strength calculation and evaluation of the mount shell was completed with the quasi-static solution method. This calculation method could consider the influence of complex factors comprehensively, such as assembly load distribution, large deformation of rubber, and contact nonlinearity on the stress distribution of the mount shell. In addition, the calculation method could solve the problem of balance between solution
Li, KeliangChen, GuozhengSun, WanyuYan, ShanhengLi, MingLiu, Baoguo
To address the issue of engine jitter at idle conditions in a specific vehicle model, an initial test of the inertial parameters of the powertrain mounting system was conducted. Utilizing the Adams software, a system model was constructed and subjected to modal analysis. The stiffness of the mounting components was selected as the optimization variable. A deterministic multi-objective optimization was performed on the system’s decoupling rate, natural frequencies, and minimum dynamic reaction force, employing the multi-island genetic algorithm. sensitivity analysis regarding the stiffness of the mounts was conducted based on DOE method. The optimized stiffness values were then re-entered into the Adams software. The results of the deterministic optimization indicated a significant enhancement in the decoupling rate of the powertrain mounting system in the primary direction of concern, a reduction in the natural frequencies, and a decrease to 43.5% of the original scheme in the minimum
Zheng, Bao BaoGuo, YimingXiao, LeiZheng, DiLi, GuohongShangguan, Wen-BinRakheja, Subhash
To enhance the transient vibration performance of the vehicle at key on and key off, a method for optimizing mount parameters of a powertrain mounting system (PMS) is proposed. Uncertainties of mount parameters widely exist in a PMS, so a method for optimizing mount parameters of a PMS, which treats the mount parameters of a PMS as uncertain, is also proposed in this paper. Firstly, a 13 degrees of freedom (DOFs) model including car body with 3 DOFs, a PMS with 6 DOFs and unsprung mass with 4 DOFs is established, and the acceleration of the active side of mounts is calculated. An experiment is carried out to measure the accelerations located at active and passive sides of each mount and the accelerations of seat track. A comparison is made between the measured and estimated accelerations, and the proposed model is validated. Two optimization methods for the PMS are proposed based on the developed 13 DOFs model. One method treats mount parameters as deterministic variables, while
Lin, ShuoYin, Zhi-HongJiang, Yong-FengSong, Yan-PingShangguan, Wen-Bin
Engine off control is conducted on parallel hybrid vehicles in order to reduce fuel consumption. It is efficient in terms of fuel economy, however, noise and vibration is generated on engine cranking and transferred through engine mount on every mode transition from EV to HEV. Engine crank position control has been studied in this paper in order to reduce vibration generated when next cranking starts. System modeling of an architecture composed of an engine, P1 and P2 motors has been conducted. According to the prior studies, there exists correlation between crank vibration level and the crank angle. Thus a method to locate pistons on a specific crank angle which results in a local minimum of vibration magnitude could be considered. The P1 motor facilitates this crank position control when engine turns off, for its location directly mounted on a crankshaft allows the system model to obtain more precise crank position estimation and improved linearity in torque control as well. For the
Park, JihyunYang, ByunghoonLIM, JongkyongKim, SungKyu
With the aim of decarbonizing the vehicles fleet, the use of hydrogen is promising solution. Hydrogen is an energy carrier, carbon-free, with high calorific value and with no CO2 and HC emissions burning in ICE. Hydrogen use in spark ignition engines has already been extensively investigated and optimized. On the other hand, its use in compression ignition engines has been little developed and, therefore, there is a lack of information regarding the combustion in ultra-lean conditions, typical of diesel engines. Several applications employ dual fuel combustion for the easy management of the PFI injection system to be applied in addition to the DI Common Rail system. However, this mode suffers from several problems regarding the management of the maximum flow rate of hydrogen into the intake. In particular, to avoid throwing hydrogen into the exhaust, injection must be started after the valve crossing. Furthermore, it is not possible to introduce gaseous fuel into the engine when the
Mancaruso, EzioCatapano, FrancescoRossetti, SalvatoreAnaclerio, GiuseppeCamporeale, SergioEpiscopo, DomenicoLaera, DavideTorresi, Marco
NVH refinement of commercial vehicles is the key attribute for customer acceptance. Engine and road irregularities are the two major factors responsible for the same. During powertrain isolators’ design alone, the mass and inertia of the powertrain are usually considered, but in practical scenarios, a directly coupled subsystem also disturbs the boundary conditions for design. Due to the upgradation in emission norms, the exhaust aftertreatment system of modern automotive vehicles becomes heavier and more complex. This system is further coupled to the powertrain through a flexible joint or fixed joint, which results in the disturbance of the performance of the isolators. Therefore, to address this, the isolators design study is done by considering a multi-body dynamics model of vehicles with 16 DOF and 22 DOF problems, which is capable to simulate static and dynamic real-life events of vehicles. Design indicators are thoroughly analyzed and validated through the rigid body modes and
Sarna, Amit KumarSingh, JitenderKumar, NavinSharma, Vikas
Key on/off (KOKO) Vibration plays a vital role in the quality of NVH (Noise Vibration and Harshness) on a vehicle. A good KOKO experience on the vehicle is desirable for every customer. The vibration transfer to the vehicle can be refined either by reducing the source vibrations or improving isolation efficiency. For the engine mounting system of passenger cars, the mounts are an isolating element between the powertrain and receiver. Various noise, Vibration, and harshness criteria must be fulfilled by mounting system performance like driver seat rail vibration (DSR), tip-in/tip-out, judder performance, DSR at idle and Key on/off Vibration. Out of these requirements, in the paper, the investigation is done on KOKO improvement without affecting other NVH parameters related to mount performance. Higher damping is required to isolate Vibration generated during the Key-on event, and lower damping is required during the idle condition of the vehicle. These contradictory damping requirements
Hazra, SandipMore, Vishwas
In today's volatile market environment, and with the change of user priorities, NVH refinement results in silent, vibration-free vehicle. The commercial vehicle industry is also starting to embrace this development in NVH vehicle refinement. There are health concerns associated with the discomfort experienced by occupants. This calls for cabins with no boom noise and less tactile vibrations. Noise within the vehicle is contributed by excitation from the Powertrain, Intake, Exhaust system, driveline, road excitations, suspension (structure borne noise) and its radiation into the air (air borne noise). This paper discusses the approach used to reduce “In-cab boom” noise in the operating speed sweep condition and seat track vibration during engine IDLE condition to improve driver comfort. In this paper NVH refinement was carried out on small commercial vehicles. Higher Seat track vibrations during IDLE and cabin boom noise during wide open throttle condition were observed during
Yeola, YogeshKharpude, YogeshKalsule, DhanajiChoudhary, AdityaSonar, SantoshNikam, Avinash
In automotive Front End Accessory Drives (FEAD), the crankshaft supplies power to accessories like alternators, pumps, etc. FEAD undergoes forced vibration due to crankshaft excitation, dynamic tension fluctuations can cause the belt to slip on the accessory pulleys. By considering the criticality of the system, when engine mounting is longitudinally to the vehicle which makes it directly exposed to the air flow containing foreign particles which may cause the damage to the FEAD system and deteriorate the intended functionality. FEAD cover is introduced in the system to enhance belt-pully system functionality by restricting the entry of foreign particles during engine operation. This paper contains a study of FEAD cover failure and provides the stepwise approach to capture such issue during novel model development for 4 cylinder naturally aspirated engine during engine bench testing. The failure mechanism was studied using various methodology such as CAE and G-Load measurement to
Patel, Hardik ManubhaiKumar, NitishChand, SubhashGupta, Vineet
Motorcycles are a preferred means of transportation in most of the countries due to its economic factor and ease in travelling. Rider comfort is an important aspect while designing a vehicle. Rider comfort is often compromised by unwanted vibrations experienced at human interface points also called as tactile points. These unwanted vibrations also affect rider’s motorcycle control and overall health. There are two major source of vibrations in a motorcycle that is engine & road inputs. In current study, a method is being explored to predict engine induced vibrations. Engine induced vibrations at various locations are simulated through multi body dynamics (MBD) and finite element (FE) simulation methods at vehicle level. Motorcycle model comprising of engine, frame and subassemblies are modeled in FE tool and then condensed to be used in MBD tool. Piston assembly, connecting rod, bearings and engine mounts are modeled in MBD tool. Vibration response resulting from unbalanced inertia
Kumar, VirenderJoshi, GauravGarg, Ankit
A robust process of specifying engine mounting systems for internal combustion engines (ICE) has been established through decades of work and countless applications. Vehicle vibration is a critical consideration in the early stage of vehicle development. Apart from comfort, it also affects the overall vehicle's performance, reliability, Buzz-squeak and rattle (BSR), parts durability and robustness. The most dynamic system in a vehicle is the powertrain, a source of vibration inputs to the vehicle over the frequency range. The mounting system supports a powertrain in a vehicle and isolates the vibration generated from the powertrain to the vehicle. In addition, it also controls the overall dynamic movement of the powertrain system when the vehicle is subjected to road load excitations and avoids contact between the powertrain and other adjacent components of the vehicle. This paper investigates the effect of the mounting position, stiffness, and progressivity on overall vehicle-level
Hazra, SandipMohare, Gourishkumar
NVH is of prime importance in buses as passengers prefer comfort. Traditionally vehicle NVH is analysed post completion of proto built however this leads to modifications, increases cost & development time. In modern approach physical validation is replaced by CAE. There are many sources of NVH in vehicle however this article is focused about the methodology to improve NVH performance of bus by analysing and improving the stiffness and mobility of various chassis frame attachment points on which source of vibrations are mounted or attached. In this study chassis frame attachment stiffness of Engine mounts and propeller shafts is focused.
Dhadiwal, Nishant SurendraPathak, RahulBijwe, VilasGore, Pandurang
IC (Internal Combustion) engines are evolved and refined over time to greater levels of technology in terms of emission, performance, NVH (Noise, Vibration & Harshness), and design philosophy. Crank-train generates a greater impact on NVH optimization due to its geometry and dynamics. Hence, more attention to mass balancing is required to minimize the negative impact on NVH. The present work demonstrates the evaluation of balancing rate of crank-train system from the first principle of couple balancing. Calculations are conducted at the concept stage to estimate an internal rotating couple balancing of crank-train system due to counterweights and rotating masses. As crankshaft weighs approximately 10-12% weight of an engine and its counter weight plays a vital role in balancing, its optimization will result in a significant impact on NVH. Therefore, based on balancing rate, engines’ crankshaft was optimized and to validate the methodologies, forces on engine mount and main bearings
Mishra, PragyaKolhe, Vivek MGhotekar, Sunil
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
Ghosh, ChiranjitAgrawal, AdheeshKarmakar, SudiptoSrivastava, ShubhamKhan, Aamir
Engine mount is an integral part of any Internal Combustion engine. It is the medium which isolates the vibrations coming from engine being transferred to the chassis or body. Engine or power plant is the main source of unbalanced vibrations. The major role of an engine mount is to reduce those vibration levels, improve ride comfort and increase the life of an engine and its parts [1]. This work determines the Test methodology development for passenger car engine mounts in the Laboratory by using Multi-axial environment [2]. This explains the details of truly Multi-axial test rig development, Drive file creation and the Durability Testing with the maintained vehicle conditions by simulating field conditions in the laboratory. The Multi-axial test rig developed with incorporation of vehicle’s both Front Drive shafts torques and One Propeller shaft which simulates the Front wheel drives and the rear prop shaft torque. Drive file generation done by using MTS controller using rpc software
Tormal, Uday BapuraoSatale, SunilV Dhage, YogeshShinde, Vikram V.
This Paper has as objective to describe the powertrain mount system and its relation with the Power Hop phenomenon. It will be present the Powertrain mounts stiffness characteristics and how the mounts manage the loads inputs. In this study, we will review a summary about powertrain mounts main characteristics to help the understanding how to establish the static and dynamic characteristics, with the engine torque applied over the system. It will be present how the Powertrain mounts shall manage the loads inputs. As a Case Study, it was applied one small passenger vehicle as hardware. This vehicle presents the powertrain mounts system as pendulum three points configuration. In addition, this vehicle presents the Power Hop phenomenon mainly in Reverse take off flat road. The required load data was collected through load cells installed on the powertrain mount system. The Power Hop phenomenon is mainly impacted by the rear mount, so the load data is related to rear mount direction X. The
Barbetti, Marcos Rogerio Sanches
Vehicle vibration is the key consideration in the early stage of vehicle development. The most dynamic system in a vehicle is the powertrain system, which is a source of various frequency vibration inputs to the vehicle. Mostly for powertrain mounting system design, only the uncoupled powertrain system is considered. However, in real situations, other subsystems are also attached to the powertrain unit. Thereby, assuming only the powertrain unit ignores the dynamic interactions among the powertrain and other systems. To address this shortcoming, a coupled powertrain and driveline mounting system problem is formulated and examined. This 16 DOF problem is constructed around a case of a front engine-based powertrain unit attached to the driveline system, which as an assembly resting on other systems such as chassis, suspensions, axles, and tires. First, the effect of a driveline on torque roll axis and other rigid body modes decoupling is examined analytically in terms of eigensolutions
Singh, JitenderSarna, Amit KumarKumar, NavinSharma, Vikas
In this paper, the influence of the decoupler-cage structure on the hitting noise of the hydraulic mount is studied, the abnormal noise of the hydraulic mount is mainly caused by the collision impact between the decoupler and the cage, the hitting noise was simulated and evaluated using calculation and experiment. a finite element model of the collision impact between the decoupler and the cage is developed, and an explicit finite element analysis is performed to obtain the time history of the vibration acceleration of the model, which is used as the boundary condition of the noise analysis. The acoustic boundary element method is used to analyze the impact noise of the decoupler-cage, and the frequency domain distribution characteristics of the impact sound pressure are obtained. The influence of different decoupler structure on the hitting noise is studied, and the recommended values for each parameter for a structure are given. The structure of a decoupler with hitting noise is
Zong, KaihuaZhao, KegangShen, DongmingTu, XiaofengShangguan, WenbinRen, Yan
Items per page:
1 – 50 of 680