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Guo J.,ESI U.S. R&D | Scott S.,ESI North America Inc. | Cao W.,CompuTherm LLC | Koser O.,Calcom ESI SW
JOM | Year: 2016

Integrated computational materials engineering (ICME) is becoming a compulsory practice for developing advanced materials, re-thinking manufacturing processing, and engineering components to meet challenging design goals quickly and cost-effectively. As a key component of the ICME approach, a numerical approach is being developed for the prediction of casting microstructure, defects formation and mechanical properties from solidification to heat treatment. Because of the processing conditions and complexity of geometry, material properties of a cast part are not normally homogeneous. This variation and the potential weakening inherent in manufacturing are currently accommodated by incorporating large safety factors that counter design goals. The simulation of the different manufacturing process stages is integrated such that the resultant microstructure of the previous event is used as the initial condition of the following event, ensuring the tracking of the component history while maintaining a high level of accuracy across these manufacturing stages. This paper explains the significance of integrated analytical prediction to obtain more precise simulation results and sets out how available techniques may be applied accordingly. © 2016 The Minerals, Metals & Materials Society


Herdy R.,Qualis Corporation | Yanez D.,ESI North America Inc.
28th AIAA Aerodynamic Measurement Technology, Ground Testing, and Flight Testing Conference 2012 | Year: 2012

The science of planning, creating, and sustaining effective and affordable infrastructure, supply chain management, and maintenance to support Civil and Government operations throughout the nation and the world is reaching unprecedented requirements to both optimize and carry the necessary bandwidth of information. In virtually every industry, the flow of information becomes the lynchpin and focal point of any true advances in Multidisciplinary Design Optimization (MDO). For this new era of MDO, new paradigms that surpass the existing approaches are needed for the exploitation of interactions among disparate disciplines to improve performance, lower cost, and shorten the product/system design cycle while simultaneously balancing potential changes in priorities. At the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD), a new software platform has emerged that has the promise to truly implement MDO with the power of the internet and the ability to orchestrate Contractor and Government resources that excel using their own familiar tools. It is called Vdot™ (coined after the first derivative of velocity, or acceleration) and is a commercial-off-the-shelf (COTS) software product offered by ESI Group. The process management methodology that Qualis Corporation has demonstrated and will soon further implement using Vdot™ has the potential to revolutionize MDO. © 2012 by Roger Herdy. Published by the American Institute of Aeronautics and Astronautics, Inc.


Tathavadekar P.,FCA U.S. LLC | De Alba Alvarez R.O.,ESI North America Inc. | Sanderson M.,FCA U.S. LLC | Hadjit R.,ESI North America Inc.
SAE Technical Papers | Year: 2015

Finite element analysis (FEA) is commonly used in the automotive industry to predict low frequency NVH behavior (<150 Hz) of structures. Also, statistical energy analysis (SEA) framework is used to predict high frequency (>400 Hz) noise transmission from the source space to the receiver space. A comprehensive approach addressing the entire spectrum (>20 Hz) by taking into account structure-borne and air-borne paths is not commonplace. In the works leading up to this paper a hybrid methodology was employed to predict structure-borne and air-borne transfer functions up to 1000 Hz by combining FEA and SEA. The dash panel was represented by FE structural subsystems and the noise control treatments (NCTs) and the pass-throughs were characterized via testing to limit uncertainty in modeling. The rest of the structure and the fluid spaces were characterized as SEA subsystems. The simulation and validation tests were performed on a single source input representing the air induction system (AIS). Sound transmission loss (STL) and vibration transfer mobility (v/F) metrics were used for correlating the model against the test data. The model was able to predict accurately the transfer functions for various measurement conditions. Future work is planned to analyze coupling loss factors across critical hybrid-junctions and expand the analysis to multiple source inputs. Copyright © 2015 SAE International.


Iqbal O.,Chrysler Group LLC | Arora K.,Chrysler Group LLC | Sanka M.,ESI North America Inc.
SAE International Journal of Engines | Year: 2014

Accurate numerical prediction of an engine thermal map at a wide range of engine operating conditions can help tune engine performance parameters at an early development stage. This study documents the correlation of an engine thermal simulation using the conjugate heat transfer (CHT) methodology with thermocouple data from an engine operating in a dynamometer and a vehicle drive cell. Three different operating conditions are matched with the simulation data. Temperatures predicted by simulation at specific sections, both at the intake and the exhaust sides of the engine are compared with the measured temperatures in the same location on the operating engine. Copyright © 2014 SAE International.


Jones D.,Queen Mary, University of London | Muller J.-D.,Queen Mary, University of London | Bayyuk S.,ESI North America Inc.
50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition | Year: 2012

This paper documents the approach used to develop the sensitivity algorithm of a commercial CFD code from ESI written in Fortran 90/95 using INRIA Tapenade version 3.6. A primitive CFD code was written in tandem with this work which is consistent with the basic algorithms used in the commercial code to present as a proof-of-concept the feasibility of an implementation and to assess the sensitivity data computed by the generated algorithms. Copyright © 2012 by Queen Mary, University of London.


Connelly T.,ESI North America Inc.
SAE International Journal of Materials and Manufacturing | Year: 2013

SEA models are used to predict the performance of acoustic packages when assessing the performance of vehicle level or body noise reduction targets. One of the challenges faced by CAE engineers is the ability to estimate the performance of different materials used in the sound package at the design stage. Analysts can use measured data in the form of insertion loss and random incidence absorption if available or can predict the performance of materials using a Biot type description. The use of the full poro-elastic Biot model for materials requires knowledge of the fluid and elastic properties, however a limp or rigid model can be used to describe the material based only on the fluid properties and this is often sufficient to describe fibrous materials. In this paper a method will be outlined which will allow the material properties of fibrous materials to be estimated from basic normal incidence data that is provided by material suppliers. This approach will then allow the effect of compression on the material properties to be predicted and the impact on the acoustic performance to be estimated. In addition it will allow the analyst to estimate the effects of increasing or reducing the fiber weight. Predictions will be compared with measured data. © 2013 SAE International.


Vaz I.,ESI North America Inc. | Washburn K.,John Deere Moline Technology Innovation | Devries L.,John Deere Worldwide Product Development
SAE Technical Papers | Year: 2011

An existing system-level Statistical Energy Analysis (SEA) model of an enclosed operator station (cab) for a combine-harvester was improved through component-level analyses using Finite Element (FE) and hybrid FE-SEA methods. At mid to high audio frequencies, airborne transmission of machine noise is a dominant path for the cab. An SEA model was created for the cab using the VA One product. When model results were validated against experimental data derived from three idealized insonification load cases, the original model did not compare well with the measured data. The structural panels used in the cab feature various non-uniform cross-sections and varying radii of curvature. The former are not appropriately modeled with standard beam stiffeners, and the latter must be accounted for by some average curvature. Geometrically accurate Finite Element (FE) models of the panels were employed to estimate parameters including effective material stiffness, and effective material density. Further, hybrid FE-SEA modeling was employed to estimate panel radiation efficiencies and account for non-uniform curvature. Using the corrected parameters, the improved SEA model compared well with measured data; it can be used with confidence to predict cab interior sound levels for different field load cases, and to explore noise control treatments. Copyright © 2011 SAE International.


Abdulnour B.,General Dynamics Corporation | Doroudian M.,ESI North America Inc. | Battoei-Avarzaman M.,ESI North America Inc.
SAE Technical Papers | Year: 2011

The performance of ground vehicles of all types is influenced by the cooling and ventilation of the engine compartment. An increased heat load into the engine compartment occurs after engine shut down. Heat is transferred from the hot components within the engine compartment by natural convection to the surrounding air and by radiation to the adjacent surfaces. The heat is then dissipated to the ambient mostly by convection from the exterior surfaces. The objective of this study is to develop a Computational Fluid Dynamics (CFD) simulation methodology to predict the airflow velocity and temperature distributions within the engine compartment, as well as the surface temperature of critical engine components during the after-boil condition. This study was conducted using a full-scale, simplified engine compartment of an armored combat vehicle. Steady-state simulation was performed first to predict the condition prior to engine shut down. A transient simulation followed to predict the flow and temperature fields during the after-boil. During after-boil, the stored energy from the engine, transmission, oil pan, and exhaust system start to transfer to the air in the engine compartment by natural convection. This causes a temporary rise in air temperature of the engine compartment environment, which could damage thermally sensitive components by approaching their critical design temperature and causes more heat transfer to adjacent surfaces and structures. The engine compartment air temperature starts to drop following the temporary rise until temperature equilibrium is reached. A significant advantage of this analytical methodology is that no physical test setup is required. The methodology can similarly be applied to passenger cars, light trucks, heavy trucks, combat vehicles, and other off-highway vehicles. Copyright © 2011 SAE International.


De Alba Alvarez R.O.,University of Southampton | De Alba Alvarez R.O.,ESI North America Inc. | Ferguson N.S.,University of Southampton | Mace B.R.,University of Southampton | Mace B.R.,University of Auckland
Finite Elements in Analysis and Design | Year: 2014

A finite element spot weld is proposed. The model is only weakly sensitive to element size, in contrast to some existing models, for which predictions of the static and dynamic responses can be strongly sensitive to the size of the elements in the substructures to which the spot weld is connected, to such an extent that numerical results may not converge. The proposed model comprises a number of multipoint constraint connections to the attached substructures, so that they may have incompatible meshes. It involves stiffness elements distributed around the perimeter of the spot weld. The case of two plates connected by three spot welds is considered. Numerical results are presented and compared with those of CWELD models and with experimental measurements. The results from the proposed spot weld model show good accuracy, low sensitivity to the element dimensions and good convergence properties. © 2014 Elsevier B.V.


Ellwood K.R.J.,Ford Motor Company | Tardiff J.L.,Ford Motor Company | Alaie S.M.,ESI North America Inc.
Journal of Coatings Technology Research | Year: 2014

The dominant method of atomizing automotive paint is through the use of rotating bell sprayers. For this class of atomizer, the problem of paint thickness across the bell has been theoretically solved on a representative geometry that includes factors such as fluid flow rate, bell speed, bell cup radius, and fluid properties. It was assumed that the paint film eventually forms uniform ligaments at the bell cup edge that break due to hydrodynamic stability during the paint spray process; thus, creating a characteristic particle size distribution for the spray. These particle size distributions will vary as the spray parameters, specifically fluid flow rate, bell speed, and bell cup radius, vary. The theoretical model that has been developed strongly correlates to the literature data available for paint droplet size from rotary bell atomizers. Expansion of the correlation of the theoretical model to paint appearance wavelength measurements, Wc and Wd, in place of droplet size provides further understanding of the effect of paint spray parameters on paint appearance. Use of these correlations can help to optimize paint appearance and improve paint spray simulation results. © 2013 American Coatings Association & Oil and Colour Chemists' Association.

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