Harvey S.M.,MSC Software
Journal of Materials Engineering and Performance | Year: 2011
Nitinol self-expanding stents are used to treat peripheral occluded vessels such as the superficial femoral artery or the carotid. The complex vessel articulation requires a stent device that is flexible and kink resistant yet durable. The present study shows how the latest advances in commercially available engineering software tools permit engineering simulations of the many aspects of the Nitinol stent design and analysis. Two stent geometries are evaluated: a helical type stent design, and a more traditional straight strut, with multiple crowns design. The fatigue performance of the two stents is compared. The results show that advanced nonlinear finite element simulations and fatigue predictions of the Nitinol stent are possible today inside realistic simulated human arteries. The finite element analysis software used in this study is SimXpert, Marc, and Mentat (MSC Software, Santa Ana, CA). © ASM International.
Son J.,MSC Software |
Lee H.-J.,Halcrow Inc.
Engineering Structures | Year: 2011
Since the terrorist attacks of 2001, concern about potential car bomb attacks on buildings and infrastructure such as bridges and tunnels has increased tremendously. Design for better performance of these structures subjected to blast load is important to prevent progressive collapse of the structure and catastrophic loss of lives. The objective of this research was to study the performance of hollow steel box and concrete-filled composite pylons of a cable-stayed bridge subjected to blast loads. Car bomb detonation on the deck is assumed to be the most likely scenario to occur. A coupled numerical approach with combined Lagrangian and Eulerian models was used to consider the interaction of the deck and pylon with the air that transfers the explosion effect to the bridge. The non-linear explicit finite element analysis program, MD Nastran SOL700 was used to simulate the spatial and time variation of the blast load as well as blast shock wave-bridge interaction response. The blast resistance of two different types of pylons was investigated in a comparative study. The study established damage patterns of the pylon and showed superior performance of the concrete-filled composite pylon over the hollow steel box pylon. For the hollow steel box pylon, the P-δ effect on the instability of the pylon subjected to blast load was significant. © 2010 Elsevier Ltd.
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: NMP.2013.2.3-2 | Award Amount: 880.60K | Year: 2013
Scope of this proposal is to establish a network of stakeholders - an Integrative Computational Materials Engineering expert group (ICMEg) - aiming at the creation of an open, global standard for information exchange between a heterogeneous variety of commercial and academic simulation tools. The vision of the ICMEg proposal is a new strategy of materials and process development, where a variety of academic and commercial simulation tools present and future can be easily combined across different process steps and bridging several length scales in a plug&play type architecture being based on an object oriented, standardized information exchange. Multi-scale in this context covers electronic, atomistic,mesoscopic and continuum models The Mission of ICMEg is to establish and to maintain a network of contacts to (1) simulation software providers around the world (2) governmental and international standardization authorities (3) ICME type users of simulation software (4) different associations in the area of materials and processing (5) academic developers of simulation software to define an ICME language in form of an open and standardized communication protocol to stimulate knowledge sharing in the field of multiscale materials design to communicate this standard worldwide to make it widely accepted to discuss and to decide about future amendments to the initial standard to establish a legal body for a sustainable further development The Approach of ICMEg to realize both its vision and its mission is to create a global network of all stakeholders in the area of ICME software and users by identifying all actors in the field of ICME related simulations creating an inventory of these stakeholders networking of all identified stakeholders in two international conferences composing a directory of all available simulation approaches establishing a common language for standardized information exchange secure sustainable further the common language by foundation of an international association identifying missing models and functionalities and proposing a roadmap for their development
Agency: Cordis | Branch: H2020 | Program: MSCA-RISE | Phase: MSCA-RISE-2014 | Award Amount: 1.05M | Year: 2015
Cell migration assays are commonly used to study wound healing, cancer cell invasion, and tissue development. Problems associated with the gap closure assays typically employed are that: (i) the stopper or scratch used to make the migration zone damages the extracellular matrix (ECM), (ii) the migration zone size is limited by the size of the stopper, and (iii) the scratched migration zone shapes and sizes are irreproducible. Cell migration is strongly coupled with the structure and mechanical properties of the ECM, and damage to the ECM alters the cell migration path. The main objective of this project is to develop a prototype novel cell migration assay, which will significantly improve the predictive power of cell-based assays while avoiding problems associated with existing assays, based on seeding cells precisely on pristine extracellular matrix tissue mimics with native-like cell-functionality and reproducible migration zones. In accomplishing this, we will also address the following questions: What are the structure-property relationships between collagen I matrices with controlled thicknesses and fibril diameter and alignment, and their mechanical and electromechanical properties? What are the critical parameters for achieving functional bonding between the substrate and the highly anisotropic viscoelastic collagen I matrices and controlling the overall mechanical properties? Does the distribution of collagen fibril polar ordering, i.e., piezoelectric domains, influence cell migration? What parameters control crimp formation in tendon-like collagen I matrices? What parameters control and explain the unusual viscoelastic properties (e.g., they not depend on the speed of deformation, at least within the interval 0.01 - 1 mm/sec) of tendon-like collagen matrices? Which cell types, including cancer cells, co-align with collagen fibril alignment or crimp direction?
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: AAT.2012.1.1-3. | Award Amount: 5.94M | Year: 2013
In order to achieve the greening of the European air transport with the deployment of low emission and low noise propulsion systems the reduction of core noise plays an important role. The ability to design low core noise aero-engines requires the development of reliable prediction tools. This development demands extensive research with dedicated experimental test cases and sophisticated numerical and analytical modelling work to broaden the physical understanding of core noise generation mechanisms. This objective is only reachable with an extensive cooperation on the European level. In this proposal Research on Core Noise Reduction (RECORD) the major aero-engine manufacturers of five different European countries collaborate to enable the design of low core noise aero-engines. In RECORD the fundamental understanding of core noise generation and how can it be reduced will be achieved by combining the research competence of all European experts in universities and research organizations working in this field of core noise. This concept of the RECORD project is completed by the technology development of small and medium size enterprises distributed in Europe. RECORD will promote the understanding of noise generating mechanism and its propagation taking the interaction of combustor and turbine into account. The importance of direct and indirect noise will be quantified. Through carefully designed experiments and extensive numerical calculations, the numerical methods and assumptions will be validated and extended. As a result, low-order models will provide a quick approach for the noise design of combustors and subsequent turbine stages while the more time-consuming and expensive LES calculation will provide a more detailed picture of the flow physics. Finally, RECORD will develop means and methods for core noise reduction.