Browse Topic: Finite element analysis

Items (3,343)
In recent decades, thermoplastics have become fundamental materials for the automotive industry, due to characteristics such as low density and increased possibility of manufacturing parts into complex geometries. Correlate the mechanical behavior of parts made with these materials, between virtual and physical testing, still poses a challenge that can be explained by the inherent nature of polymeric compounds, which generally exhibit a complex microstructural composition. This study uses a Bumper Grille made of Acrylonitrile Styrene Acrylate (ASA) as case study. This part is a fundamental external vehicle component, not only for safety criteria, but also for consumer satisfaction. To analyze the structural behavior of a vehicle components such as a Grille, Computer Aided Engineering (CAE) tools with the Finite Element Method (FEM) are commonly applied, in which a good understanding of the analysis setup and physical properties used to define the model are essential. For models built
Ferreira, Gabriel RamosSouza Silva, PauloSoares, Annelise Heidrich PietroMaciel, Ronei SantosCarvalho, Gimaézio GomesSanchez, Jorge Romero
With the growing demand for electric vehicles (EVs), ensuring the safety and efficiency of battery systems is critical. This paper presents a methodology integrating 3D Finite Element Methods (FEM) and Computational Fluid Dynamics (CFD) to analyze battery systems, effectively mitigating thermal runaway phenomena. By combining FEM and CFD, our methodology provides a comprehensive approach to assess thermal management strategies within battery systems. This integration enables engineers to accurately simulate thermal behavior, predict hotspots, and optimize cooling strategies, thereby mitigating the risk of thermal runaway. Furthermore, our methodology minimizes the reliance on costly and time-intensive physical prototypes and testing. By leveraging virtual simulations, engineers can rapidly iterate through design modifications, assess their impact on thermal performance, and make informed decisions early in the development process. This article demonstrates the efficacy and accuracy of
Melo, Caiuã CaldeiraAraujo, Pedro HenriqueCastro Orefice, FabioCury, Davi MachadoVieira, Tiago Augusto SantiagoAbdu, Aline Amaral QuintellaMonteiro, Henrique Carlos
The use of parts with notches or some geometric discontinuity is common in the industrial field. In the aerospace industry, it is common to use components made of composite materials with holes for fixing components. Thus, understanding the behavior of these materials, especially when they present holes or geometries that act as stress concentrators, becomes crucial to assess the possible reduction in strength due to presence of these notches. This study aims to determine the stress concentration factor in circular-hole composite laminates made of PPS (Polyphenylene Sulfide) with 5 HS carbon fiber. For determining stress concentration factor, analytical methods using the point stress criterion, computational numerical simulation through FEA (finite element analysis), and experimental validation of proposed model were used. Mechanical tests of specimens with dimensions adapted from ASTM D3039 standard were performed, which were instrumented using strain gauges in the transverse and
De Almeida, Fernando Cristian SoaresOliveira, Geraldo Cesar RosarioGuidi, Erick Siqueira
Design validation plays a crucial role in the overall cost and time allocation for product development. This is especially evident in high-value manufacturing sectors like commercial vehicle electric drive systems or e-axles, where the expenses related to sample procurement, testing complexity, and diverse requirements are significant. Validation methodologies are continuously evolving to encompass new technologies, yet they must be rigorously evaluated to identify potential efficiencies and enhance the overall value of validation tests. Simulation tools have made substantial advancements and are now widely utilized in the development phase. The integration of simulation-based or simulation-supported validation processes can streamline testing timelines and sample quantities, all the while upholding quality standards and minimizing risks when compared to traditional methods. This study examines various scenarios where the implementation of advanced techniques has led to a reduction in
Leighton, MichaelTuschkan, AlwinPlayfoot , Ben
Vehicles equipped with automated driving systems (ADS) may have non-traditional seating configurations, such as rear-facing for front-row occupants. The objectives of this study are (1) to generate biomechanical corridors from kinematic data obtained from postmortem human subjects (PMHS) sled tests and (2) to assess the biofidelity of the Global Human Body Models Consortium (GHBMC) 50th male (M50-O) v6.0 seated in an upright (25-deg recline) Honda Accord seat with a fixed D-ring (FDR) in a 56 km/h rear-facing frontal impact. A phase optimization technique was applied to mass-normalized PMHS data for generating corridors. After replicating the experimental boundary conditions in the computational finite element (FE) environment, the performance of the rigidized FE seat model obtained was validated using LSTC Hybrid III FE model simulations and comparison with experiments. The most recent National Highway Traffic Safety Administration (NHTSA) Biofidelity Ranking System (BRS) method was
Pradhan, VikramRamachandra, RakshitStammen, JasonKracht, CoreyMoorhouse, KevinBolte, John H.Kang, Yun-Seok
This study investigates into the mechanical performance of load vehicle brake liners that have been enhanced with nanomaterials, employing Finite Element Analysis (FEA). The analysis involves a detailed investigation of structural, thermal, and wears characteristics to evaluate the overall performance of the brake liners. This research aimed to reduce the stress and pressure exerted on vehicle brakes during braking by conducting a comprehensive stress analysis of the braking system. Finite Element Analysis serves as a powerful tool for simulating and assessing the behavior of complex structures under varying conditions. In this research, the study employs FEA techniques to model and analyze the load vehicle brake liners, considering the incorporation of nanomaterial’s, with a special emphasis on materials like Al2O3.The aim is to gain a profound understanding of how these nanomaterial’s influence and improve the mechanical aspects of the brake liners
Kumar, N. MathanThillikkani, S.Kannan, S.Soundararajan, S.Bharti, Kundan
Research areas in Road furniture have become critical due to the rising incidence of road accidents and fatalities. Enhancing road attributes such as crash barriers, crash cushions, crash poles, and emergency communication systems can significantly reduce these fatalities. Among these, crash barriers promise particular attention as they serve as immediate safety mechanisms. When a vehicle loses control, crash barriers can effectively mitigate the severity of accidents by restraining the vehicle and preventing more severe outcomes. This paper focuses on the performance of a novel steel-wood hybrid crash barrier with perforated post parallel to vehicles direction, designed to enhance road safety in hilly areas. Utilizing finite element analysis (FEA) in LS-DYNA software, renowned for simulating structural deformation under loading, we evaluated the structural response and crashworthiness of the hybrid barrier under various impact scenarios. Our simulations assessed the barrier's
Bendre, SagarDas, AlakenduJaiswal, Manish
Casted Aluminum alloys are prone to manufacturing defects such as porosity, voids, and inclusions. Modern casting systems, with their advanced technologies, have made strides in foreseeing and mitigating these flaws. Yet, apart from inclusions and porosity remain stubbornly persistent, never fully eradicated. The challenge of predicting the exact sizes and shapes of these flaws adds another layer of complexity. Consequently, the precise predictions of stress-strain fields, while accounting for casting defects are critical to ensure the durability and integrity of casted components. A computational finite-element based simulation performed to resemble the experimental tensile test. A quarter symmetric numerical specimens are investigated with distinct sizes and shapes of pores/voids. The tensile strength along with the elasto-plastic stress-strain state in the vicinity of randomly distributed voids/pores are determined and compared with defects-free model. The local stress and strain
T, KalingaSahu, AbhishekChirravuri, BhaskaraMiller, RonaldXu, Siguang
In demanding automotive coolant applications characterized by extreme pressure and temperature conditions, a variety of Mechanically Attached Fittings (MAFs) are offered by multinational corporations (MNCs). These engineered fittings have been designed to meet the rigorous requirements of various industries, providing a cost-effective and reliable means to seal engine/motor coolant hose joints. Mechanical fitting assemblies are critical in various engineering systems and are used for connecting various fluid-carrying locations. Understanding leakage phenomena from MAFs is essential for ensuring their reliability and efficiency. This study explores the deployment of Fluid Pressure Penetration Technique (FPPT) available in Abaqus FEA software to comprehensively analyze leakage paths in mechanically joined fittings. The FPPT offers a systematic approach to model fluid penetration behavior within fitting joints under many loading conditions. By utilizing Abaqus software, a powerful finite
Aher, Ravi KautikJivani, ChinmayOlesnavich, MichaelLima, JosePillai, Pramod
Electrified powertrain is the essential need to meet the C02 and NOX emissions compliance. Thereby focus of automotive industry is shifting towards to Electric Vehicle (EV). Thermal Runaway (TR) is still a big challenge to the safety of the EV. The major cause of TR is internal short-circuit of batteries under external mechanical abuse. When Anode and cathode of the battery comes in contact and short circuit happens. Internal short circuit is causing high amount of current flow and energy generation which leads to high increase in temperature. The approach that is used till date by OEMs is to protect the battery pack from structural damage during crash resulting into overdesigning of the vehicle. In this paper, detailed FE modeling of the battery system is considered for evaluating internal short circuit and TR. Solid Randle circuit is used for Multiphysics coupling simulation in Ls-dyna. Solid Randle circuits solves this Multiphysics and derives these electrical and thermal parameters
Jain, TriptiBonala, SastryDangare, Anand
Linear dynamics simulations are performed on engine components to ensure structural integrity under dynamic loading. The finite element model of the engine assembly must be prepared accurately to avoid under or over design of the engine components. Flexible hoses are present at pipe routings and modeling them in simulations is a challenge because the stiffness of the composite is not known. The hose under study in this paper is a rubber composite with a knitted reinforcement layer. A multiscale modelling approach is presented to characterize the hose stiffness. A representative volume element geometry i.e., unit cell representation of the composite, consisting of the knitted yarn and surrounding rubber is used to establish orthotropic elastic properties at microscale, by performing finite element homogenization using the ANSYS material designer module. The homogenized properties are assigned to the macroscale hose geometry to perform modal analysis simulation in free-free and fixed
Ashodiya, Jay VirendraJayachandran, JanarthananSanthosh, B
Investigation of clunking noise in a steering system fitted into a test vehicle indicated radial lash in sliding bushings, which are press fitted into housings, as one of the possible causes for clunk. To study the behavior of sliding bush under the influence of assembly clamp loads, manufacturing tolerances and road loads, sliding bushings are modelled in more detail in the steering system finite element models. Further for correlating the bushing measurements from test vehicle to the finite element model, a radial lash output is derived which is not directly available in finite element software. Finally, the correlated model is used to assess the updated design and check for radial lash improvement
Badduri, JaideepPandey, Ashish
Calibrated Accelerated Life Testing (CALT) is a sequential and quantitative method for Accelerated Life Testing (ALT). Its design aims to optimize test efficiency by minimizing both test duration and sample size while estimating product life. In the CALT context, the focus is on testing samples under three or more distinct stresses or loads to estimate the life span/BX life, which is a crucial parameter in reliability estimation. Determining the first load in CALT typically involves exploratory testing on a limited number of specimens and relies heavily on engineering judgments such as analyzing Finite Element Analysis (FEA) outcomes, referencing test data from comparable designs and materials, and considering stiffness results etc. This often leads to challenges in accurately identifying the first load/stress. To address this issue, we propose a systematic step-stress test approach instead of exploratory testing. This approach aims to efficiently identify the first load in CALT. The
Patidar, NitinSoma, Nagaraju
This study proposes a novel energy absorber design by incorporating a screw into the groove of crash boxes and evaluates its performance using finite element analysis (FEA). The methodology integrates CAD modelling, material characterization, and detailed analysis of simulation data to assess the influence of single screw integration on crash box performance. LS-Dyna simulation was employed to investigate the behaviour of Aluminium Alloy 5052 (Al5052) crash boxes with screws in the groove. Results from FEA reveal key performance indicators such as displacement, stress, strain, internal energy, and acceleration across various crash box thicknesses. Analysis of the data demonstrates that as the thickness of the crash box increases, there is a decreasing trend where displacement, stress levels, and acceleration are concerned. The presence of the screw leads to a reduction in stress levels and acceleration across different thicknesses of crash boxes, indicating superior performance. These
R, Teddy SamuelMayakrishnan, Jaikumar
A temperature dependent cohesive zone model considering the thermo-mechanical fatigue loadings are used to simulate and predict the failure process of solder joint interface in power electronics modules. Cohesive Zone Models (CZMs) are gaining popularity for modeling the fracture and fatigue behavior in various class of materials such as metals, polymers, ceramics, and their composite materials. Unlike the traditional fracture mechanics which considers concept of infinitesimal crack, CZMs assume a fracture process zone in which external energy is distributed in vicinity to propagating crack. In order to predict the fatigue-fracture process under thermo-mechanical cyclic loading, a damage accumulation variable is utilized. The calculation of damage is performed using a progressive mechanism, and the cohesive zone model is updated to reflect the present level of damage. The existing cohesive forces are influenced by both the current damage status and the extent of separation
Singh, Praveen KumarSahu, AbhishekChirravuri, BhaskaraMiller, Ronald
In this paper, a comprehensive analysis of NVH in electric powertrains due to electromagnetic sources is presented. The spatial harmonics model of the traction motor, which is dependent on the motor design structure, rotor poles, stator teeth, and slots, is used for the analysis of the electromagnetic forces from the motor in the electric powertrain. The time harmonics model of the injected current of the motor dependent on the drive electrical circuit and control strategy is also considered for the electromagnetic force calculation. A complete workflow of this electromagnetic NVH analysis for electric powertrain covering the spatial harmonics and time harmonics model is presented. The spatial harmonics model result is presented as flux linkage with respect to dq-axes current and rotor position. The time harmonics are also presented by the injected current of the motor. In addition, a set of operating points on the torque-speed boundary of the traction motor is selected and results are
Joshi, NakulKumar, VinitTsoulfaidis, AntoniosHuang, ZhenhuaSchmaedicke, MarcelFialek, GregoryZhang, DapuWimmer, Joe
This study investigated the contact pressure distribution of three combustion seal designs for fuel injectors using both experimental techniques and finite element analysis (FEA). The designs tested included the baseline seal (Design #1), a conical seal (Design #2), and the current production seal (Design #3). In phase 1, a 2D axisymmetric FEA was conducted under worst-case torque conditions (67.8 Nm) to simulate contact pressure, with an axial load of 10 kN and combustion pressure of 21.3 MPa applied to the injector assembly. Phase 2 employed Fuji films to measure the pressure distribution at higher torques (89.5 and 115.2 Nm) in a more realistic scenario, incorporating challenges such as misalignment and eccentric loading. During this phase, Fuji film shearing was a significant challenge, complicating the accurate assessment of pressure profiles. Design #1 failed to maintain the minimum threshold contact pressure of 70 MPa over a 1 mm length, leading to potential leakage. Design #2
Kaliyanda, Aneesh
A novel design for a radial field switching reluctance motor with a sandwich-type C-core architecture is proposed. This approach combines elements of both traditional axial and radial field distribution techniques. This motor, similar to an in-wheel construction, is mounted on a shared shaft and is simple to operate and maintain. The rotor is positioned between the two stators in this configuration. The cores and poles of the two stators are separated from one another both magnetically and electrically. Both stators can work together or separately to produce the necessary torque. This adds novelty and improves the design’s suitability for use with electrical vehicles (EVs). A good, broad, and adaptable torque profile is provided by this setup at a modest excitation current. This work presents the entire C-core radial field switched reluctance motor (SRM) design process, including the computation of motor parameters through computer-aided design (CAD). The CAD outputs are verified via
Patel, Nikunj R.Mokariya, Kashyap L.Chavda, Jiten K.Patil, Surekha
ABSTRACT The foundation of the theory of functionally graded plates with simply supported edges, under a Friedlander explosive air-blast, are developed within the classical plate theory (CPT). Within the development of the theory, the two constituent phases, ceramic and metal, vary across the wall thickness according to a prescribed power law. The theory includes the geometrical nonlinearities, the dynamic effects, compressive tensile edge loadings, the damping effects, and thermal effects. The static and dynamic solutions are developed leveraging the use of a stress potential with the Extended-Galerkin method and the Runge-Kutta method. Validations with simpler cases within the specialized literature are shown. The analysis focuses on how to alleviate the effects of large deformations through proper material selection and the proper gradation of the constituent phases or materials
Hause, Terry
ABSTRACT Two relevant materials found in ground vehicle underbody armor/hull designs are Aluminum 2139-T8 and RHA Steel (Class I). These are 2 very important materials that need a thorough understanding of their high-strain rate behavior. The Johnson-Cook Deformation (JC-D) model at this time is the most preferred constitutive material model to utilize for high-strain (large deformation) blast simulations. The JC-D Model contains five empirically-based input parameters which can be determined traditionally through a series of uniaxial laboratory tests where each target parameter is isolated, while the remaining parameters are held constant. There are many criticisms and problems with this approach. The objective of this two part paper is to present and adopt a more accurate approach with less criticism to the determination of these five input parameters through both a sensitivity study to determine which input parameters are the most sensitive to a particular chosen response which in
Hause, TerrySheng, Jianping
ABSTRACT The shapes of Improvised Explosive Devices (IED) used by insurgents in recent conflicts are complex and can take many forms. To model unique shapes that are embedded in the soil, in addition to the actual shape of the High Explosive (HE), adds to the complexity of simulating the mine blast event. By considering an artillery shell as the container, further complicates the analysis because fragmentation of the shell has to be included. Unfortunately, this complex IED is not uncommon and in order to develop protective structures for our soldiers and civilians, finite element techniques are employed. The work presented is an investigation of how to do this modeling using the explicit non-linear transient finite element software, the IMPETUS Afea Solver®. The first step is a large sensitivity study of an explosive driven expansion of a simple cylinder and the outcome influence of nine design variables, leading to hundreds of computational hours. The modeling approach chosen for the
Rasico, James G.Newman, Craig A.Jensen, Morten Rikard
ABSTRACT The objective in this paper is to understand the challenges of making additive manufacturing a future source of supply for the Department of Defense through the redesign of a part for metal laser Powder Bed Fusion. The scope of this paper involved the redesign of a single cast-and-machined part for an Army ground vehicle system. The component was redesigned using topology optimization based on suitable replacement materials and design data from the representative part. In parallel, a brief review of AM standards identified a process to qualify the component through post-processing, non-destructive evaluation, and witness testing. Alongside this redesign analysis, a brief cost analysis was conducted to understand the cost associated with manufacturing and qualifying this part for multiple AM materials. The resulting analysis demonstrated that for this component, which was subject to high design loads, Scalmalloy, Ti-6Al-4V, and 17-4PH Stainless Steel could produce the most cost
Burke, RorySimpson, Timothy
ABSTRACT The durability and reliability of military vehicle systems are traditionally tested at Aberdeen Proving Ground by driving vehicles on a set of paved roads, secondary roads, trails, and cross-country terrains. However, driving mile-for-mile over the proving ground test courses is very time-consuming and costly. The U.S. Army Aberdeen Test Center (ATC) has recently conducted accelerated durability tests of wheeled vehicles using two different methods: accelerated hardware-in-the-loop simulation and accelerated field testing. This paper discusses the methods used to date and associated technical details to highlight options for future accelerated testing
Ramsey, GregSchultz, GregClerkin, James
ABSTRACT In this work, Abrams tank track system T-158LL backer pad elastomer self-heating and fatigue behavior was characterized experimentally, and the backer pad design was digitally twinned to show how complex in-service conditions can be evaluated virtually. The material characterization included measurement of the thermal properties and dissipative characteristics of the rubber compound, as well as its fatigue crack growth rate curve and crack precursor size. The analysis included 1) a structural finite element analysis of the backer pad in operation to obtain the load history, 2) a thermal finite element analysis to obtain steady-state operating temperature distribution within the backer pad, and 3) a thermo-mechanical fatigue analysis using the Endurica CL fatigue solver to estimate the expected service life and failure mode of the backer pad. As validation, experiments were conducted on the backer pad to measure operating temperature, fatigue life, and failure mode over a
Mars, William V.Castanier, MatthewOstberg, DavidBradford, William
ABSTRACT The mobility performance of off-road vehicles involves the interaction between the vehicle tires and soil that requires more advanced and robust simulation methods to accurately model [4]. The finite element method (FEM) [6][7][8][9] can be a good approach to compute deformations of the tire and soil, but analytical constitutive models of soil used in FEM typically lack accuracy, for example in problems involving large deformations. Discrete element method (DEM) [12][13][14] is a more accurate approach to capture the soil constitutive features, but for the simulations of a large ground vehicle traversing over deformable terrain, the current DEM methods require modeling of soil particles at a size too large to be real, and the simulation times are prohibitively large. It is proposed in this work to develop a multi-scale FEM-DEM deformable terrain model for physics-based off-road mobility simulation to facilitate a cross-scale understanding of granular material behavior that
Ruan, YeefengJayakumar, ParamsothyLeiter, KennethKnap, Jaroslaw
ABSTRACT This paper addresses the balance of performance parameters of occupant survivability and vehicle mobility during trade study analysis and simulation for the TARDEC Demonstrator for Novel Design (DFND) vehicle concepts. Occupant survivability and vehicle mobility are often competing attributes in the design of current armor protected tactical and combat ground vehicles. Increased armor weight and high stand-off height parameters are favorable for occupant survivability during underbelly blast events but are detrimental to vehicle dynamics mobility performance. TARDEC and Pratt & Miller Engineering are implementing a motorsports based design process and simulation approach using a holistic systems engineering trade study to develop potential concepts that maximize force protection, vehicle mobility, and vehicle survivability. A number of specialized simulation tools including hypervelocity explicit finite element analysis and multi-body simulation are used interactively to
Kaplin, Casey A.Houghton, Kristian B.
ABSTRACT Conceptual design of automotive structures has received substantial research attention in recent years in order to speed up vehicle development and innovation. Although several structural optimization methods have been employed in concept design, there still exists lack of efficient design tools to produce initial design shapes with less problem dependency, less computation-intensive analysis and more design flexibility. In this paper, an innovative Computer Aided Engineering (CAE) approach based on an integrated Genetic Algorithms(GA) and Finite Element (FE) optimization system has been studied and implemented for efficient conceptual design of automotive suspension system related structural part. Integration of GA provides the method a great amount of design flexibility and robustness that increases possibility of finding more efficient and innovative design shapes of the structure
Islam, Mohammad RefatulMotoyama, Keiichi
ABSTRACT BAE Systems has departed from traditional design rules of thumb and implemented a full-vehicle durability fatigue life analysis process at the design concept level to support lighter weight component designs. The durability process includes derivation of test duty cycles, generation of virtual loads from vehicle dynamic simulations, cascading of hundreds of channels of suspension attachment loads, and prediction of accumulated damage/fatigue life for both quasi-static and transient responses using a finite element vehicle structural model. The fatigue analysis process is typically deterministic, however the stochastic nature of the loads, material properties, and build variations should also be considered to ensure a robust durability process. The process is demonstrated on a heavy wheeled-vehicle platform using a generic duty cycle with examples shown at each stage of the process. This study additionally demonstrates the effects of variability of loads, materials, and
Purushothaman, NammalwarJayakumar, ParamsothyCritchley, JamesDatta, SandipPisipati, Venkat
ABSTRACT Accurate land mine modeling has been the subject of substantial research over the past 15 years. Many methods have been investigated using various computational codes, and LS-DYNA remains a popular choice because of its capabilities for modeling full armored vehicles. Prior research discloses a range of strategies that have been utilized, including various numerical methods such as FEM, ALE, SPH, and DEM. This paper discusses a hybrid FEM-SPH land mine modeling approach using LS-DYNA that provides high accuracy at reasonable computational expense. While stable and phenomenologically correct, accuracy issues persisted with this approach, which tended to produce the typical SPH under-prediction of impulse. However, adjusting two key parameters– smoothing length and coefficient of restitution– were found to resolve the impulse under-prediction. The final land mine modeling strategy provided an accurate all-Lagrangian approach for application to full-scale vehicle models in LS
Barsotti, MattO’Hare, EddieSammarco, EricRasico, James G.Gerst, DavidNewman, Craig A.
ABSTRACT Shape reconstruction for nondestructive evaluation (NDE) of internal defects in ground vehicle hulls using eddy current probes provides a rationale for determination of when to withdraw vehicles from deployment. This process requires detailed finite element optimization and is computationally intensive. Traditional shared memory parallel systems, however, are prohibitively expensive and have limited central processing units (CPUs), making speedup limited. So parallelization has never been done. However, a CPU that is connected to graphics processing units (GPUs) with effective built-in shared memory provides a new opportunity. We implement the naturally parallel, genetic algorithm (GA) for synthesizing defect shapes on GPUs. Shapes are optimized to match exterior measurements, launching the parallel, executable GA kernel on hundreds of CUDA™ (Compute Unified Device Architecture) threads to establish the efficiencies
Karthik, Victor U.Sivasuthan, SivamayamRahunanthan, ArunasalamJayakumar, ParamsothyThyagarajan, Ravi S.Hoole, S. Ratnajeevan H.
ABSTRACT FBS Inc. is working with the TARDEC Electrified Armor Lab to develop a nondestructive structural health monitoring technology for composite armor panels that utilizes an array of embedded ultrasonic sensors for guided wave tomographic imaging. This technology would allow for periodic or real-time monitoring of armor integrity while being minimally intrusive and adding negligible weight. The technology is currently being developed and tested in pseudo composite armor panels and efforts are focused on reducing sensor array density, improving sensor integration procedures, and maximizing system sensitivity to damage. In addition to experimental testing and development, FBS is developing a highly-automated finite element model generation and analysis program to be used in conjunction with Abaqus/Explicit commercial finite element software. This program is specifically dedicated to modeling guided wave propagation in pseudo composite armor panels between embedded ultrasonic sensors
Borigo, Cody J.Bostron, JasonRose, Joseph L.Owens, Steven E.Reynolds, Thomas P.Meitzler, Thomas J.
ABSTRACT Researchers at Caterpillar have been using Finite Element Analysis or Method (FEA or FEM), Mesh Free Models (MFM) and Discrete Element Models (DEM) extensively to model different earthmoving operations. Multi-body dynamics models using both flexible and rigid body have been used to model the machine dynamics. The proper soil and machine models along with the operator model can be coupled to numerically model an earthmoving operation. The soil – machine interaction phenomenon has been a challenging matter for many researchers. Different approaches, such as FEA, MFM and DEM are available nowadays to model the dynamic soil behavior; each of these approaches has its own limitations and applications. To apply FEA, MFM or DEM for analyzing earthmoving operations the model must reproduce the mechanical behavior of the granular material. In practice this macro level mechanical behavior is not achieved by modeling the exact physics of the microfabric structure but rather by
Alsaleh, Mustafa
ABSTRACT The presented work discusses how to make a V/L analysis of a vehicle based on an RHA equivalence. It is shown how the approach works using small examples and an impact of an M1 helmet. Further, different V/L analyses of the GAZ-2975 vehicle are displayed. Considered Response parameters are the VAA damage maps, Expected Protection Capability plot, and damage area fractions. Explicit Finite Element models are used to find the critical RHA equivalent armor thickness at normal impact. It is done with terminal ballistic models for three materials; RHA, Aluminum 5083-H116, and Armox 500T. The values found are used in a V/L analysis. A sensitivity study of eight relevant V/L design parameters is carried out on the driver side section of the GAZ-2975 vehicle with an EPC value as the response parameter. Citation: Morten Rikard Jensen, Steven Grate, “Procedure for Fast Ballistic Vulnerability Simulation of Armored Vehicles Supported by Finite Element Results and an Extensive Numerical
Jensen, Morten RikardGrate, Steven
ABSTRACT For GDLS as an OEM in the defense industry working primarily as a system integrator, it is mission critical to develop a platform to weight/gauge/tradeoff requirements of various sub-systems in the final system product. Knowing sub-system performances in the final system on a physics bases, enables the system integrator more active roles in product R&D for requirement tradeoffs and price tag controls, instead of being passively driven solely by suppliers’ perspectives. Designing a light weight system while maintaining their mission profile, can lead to the use of more flexible structures thereby imposing additional dynamics affecting the integration of weapon systems into the vehicle structure. Added to this, the dynamics of electromechanical actuators, mechanical tolerances and discrete controllers, creates an environment, each of which is defined by its characteristic physics. This paper discusses a multi-physics approach used different brand named solvers best for different
D’Onofrio, DavidKuang, Zhian
Abstract: An idealized concept of a v-hull vehicle design for blast analysis has been studied in two different commercial software packages and results are compared to one another. The two software packages are different in nature: one code is an Eulerian Computational Fluid Dynamics (CFD) Finite Volume Solver while the other code is a Lagrangian Finite Element Analysis (FEA) Solver with the ability to couple structures to fluids through a special technique called Arbitrary Lagrangian Eulerian (ALE). The simulation models in this paper have been set up for both CFD and FEA using a commercial pre-processing tool to study the effect of an idealized blast on the vehicle configuration: A pressure blast charge has been placed under the center of the vehicle at the symmetry line. The charge is composed of a prescribed pressure and a temperature pulse in a medium with the properties of air. In the CFD solver, an explicit unsteady solver has been chosen for analysis purposes. This was done
Khatib-Shahidi, BijanSmith, Rob E.
ABSTRACT Vehicle design is a complex process requiring interactions and exchange of information among multiple disciplines such as fatigue, strength, propulsion, survivability, safety, thermal management, stealth, maintenance, and manufacturing. Simulation models are employed for assessing and potentially improving a vehicle’s performance in individual technical areas. The vehicle’s characteristics influence the performance in all the different attributes. Challenges arise when designing a vehicle for improving mutually competing objectives, satisfying constraints from multiple engineering disciplines, and determining a single set of values for the vehicle’s characteristics. It is of interest to engage simulation models from the various engineering disciplines in an organized and coordinated manner for determining a design configuration that provides the best possible performance in all disciplines. This paper presents an approach that conducts optimization analysis for a complex
He, JimHart, Christopher G.Vlahopoulos, Nickolas
ABSTRACT The modeling of a buried charge is a very complex engineering task since many Design Variables need to be considered. The variables in question are directly related to the method chosen to perform the analysis and the process modeled. In order to have a Predictive Tool two main objectives have to be carried out, the first is a verification of the numerical approach with experimental data, the second objective is a sensitivity study of the numerical and process parameters. The emphasis of the present study covers the second objective. To perform this task a comprehensive sensitivity study of fourteen Design Variables was completed which required 1000+ computational hours. The modeling approach that was chosen was the Discrete Particle Method (DPM) to model the Soil and HE and the Finite Element Method for the Structure. The basis for the study was a blast event applied to a model of the TARDEC Generic Vehicle Hull. The Response Parameter was chosen to be the Total Blast Impulse
Jensen, Morten RikardSmith, Wilford
ABSTRACT Timely part procurement is vital to the maintenance and performance of deployed military equipment. Yet, logistical hurdles can delay this process, which can compromise efficiency and mission success for the warfighter. Point-of-need part procurement through additive manufacturing (AM) is a means to circumvent these logistical challenges. An Integrated Computational Materials Engineering framework is presented as a means to validate and quantify the performance of AM replacement parts. Statistical modeling using a random forest network and finite element modeling were to inform the build design. Validation was performed by testing coupons extracted from each legacy replacement parts, as well as the new additively manufactured replacement parts through monotonic tensile and combined tension-torsion fatigue testing. Destructive full hinge assembly tests were also performed as part of the experimental characterization. Lastly, the collected experimental results were used to
Gallmeyer, Thomas GDahal, JineshKappes, Branden BStebner, Aaron PThyagarajan, Ravi SMiranda, Juan APilchak, AdamNuechterlein, Jacob
ABSTRACT With the development of the next generation of military vehicles, the demand for significant amounts of electrical power is increasing, making the design of electrical machines, such as the vehicle alternator, integral to the powertrain design. This shows the importance of the machines’ size and efficiency, and the great influence they will have on the vehicle powertrain design process. In this paper, a finite-element-based scaling technique, capable of quickly generating torque-speed curves and efficiency maps for new machine designs, is improved to have two dimensional scaling factors instead of scaling the dimensions uniformly, thus increasing the flexibility of the tool. First, a magnetostatic finite-element-analysis (FEA) is conducted on a base machine, producing data such as torque, flux linkage, and demagnetizing field intensity in the permanent magnets, over a wide range of current magnitudes and phase angles. Then, based on the dimensional and winding scaling factors
Wang, YuanyingHofmann, HeathIvanco, AndrejRizzo, Denise
ABSTRACT The dynamic response of two multibody systems, a planar mechanism and a spatial robot, are generated using an explicit time integration finite element code and a multi-body dynamics code. Comparisons are made of the dynamic solution including body motion, joint constraint forces, conservation of energy, and CPU time. While finite-element simulation offers accurate modeling of structural flexibility, multibody dynamic simulation demonstrates the capability to produce accurate and efficient results
Jayakumar, ParamsothyWasfy, Tamer
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