Finite element analysis of contact stresses in elastic double-layer systems under normal load

The stress analysis of dovetail attachments presents some challenges. These challenges stem from the high stress gradients near the edges of contact and from the nonlinearities attending conforming contact with friction. To meet these challenges with a finite element analysis, refined grids are needed with mesh sizes near the edges of contact of the order of one percent of the local radii of curvature there. A submodeling procedure is described which can provide grids of sufficient resolution in return for moderate computational effort. This procedure furnishes peak stresses near contact edges which are converging on a sequence of three submodel grids, and which typically do converge to within about five percent.

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Finite Element Analysis of Accessorial Equipments for Carring the Wounded by Airliners Based on MSC.PATRAN

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.389.1065 ◽

2013 ◽

Vol 389 ◽

pp. 1065-1068

Author(s):

Li Tang ◽

Jing Tao Yue ◽

Yin Zhang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Double Layer ◽

Design Criteria ◽

Element Analysis ◽

Under Five

According to the design criteria referred to CCAR-25,the static strengths of accessorial equipments (single stretcher-supporting equipment, double layer stretcher-supporting equipment and nursing-type unit) and the track-mounting mechanism applied to fix the accessorial equipments to the seat tracks of the airliner are analyzed under five loads by using the software MSC.PATRAN. Based on the analysis results, the strengths of the accessorial equipments will be checked, the structures can satisfy the requirements of strength.

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Knee Arthroplasty Bone Model with Double Layer Array Synthesis and Evaluation of Finite Element Analysis

Sakarya University Journal of Science ◽

10.5505/saufbe.2012.46036 ◽

2012 ◽

Vol 16 (3) ◽

pp. 189-194

Author(s):

Ismail Hakki Korkmaz ◽

Irfan Kaymaz ◽

Fatih Medetalibeyolu ◽

Omer Selim Yildirim

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Double Layer ◽

Knee Arthroplasty ◽

Element Analysis ◽

Bone Model

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Mechanical Response of PEKK and PEEK As Frameworks for Implant-Supported Full-Arch Fixed Dental Prosthesis: 3D Finite Element Analysis

European Journal of Dentistry ◽

10.1055/s-0041-1731833 ◽

2021 ◽

Author(s):

Regina Furbino Villefort ◽

Pedro Jacy Santos Diamantino ◽

Sandra Lúcia Ventorin von Zeidler ◽

Alexandre Luiz Souto Borges ◽

Laís Regiane Silva-Concílio ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

High Performance ◽

Mechanical Response ◽

Normal Load ◽

Von Mises Stress ◽

Lower Stress ◽

Element Analysis ◽

Fixed Dental Prosthesis

Abstract Objective Polymeric framework represent an innovative approach for implant-supported dental prostheses. However, the mechanical response of ultra-high performance polymers as frameworks for full-arch prostheses under the “all-on-four concept” remains unclear. The present study applied finite element analysis to examine the behavior of polyetherketoneketone (PEKK) and polyetheretherketone (PEEK) prosthetic frameworks. Materials and Methods A three-dimensional maxillary model received four axially positioned morse-taper implants, over which a polymeric bar was simulated. The full-arch prosthesis was created from a previously reported database model, and the imported geometries were divided into a mesh composed of nodes and tetrahedral elements in the analysis software. The materials were assumed as isotropic, elastic, and homogeneous, and all contacts were considered bonded. A normal load (500 N magnitude) was applied at the occlusal surface of the first left molar after the model was fixed at the base of the cortical bone. The microstrain and von-Mises stress were selected as criteria for analysis. Results Similarities in the mechanical response were observed in both framework for the peri-implant tissue, as well as for stress generated in the implants (263–264 MPa) and abutments (274–273 MPa). The prosthetic screw and prosthetic base concentrated more stress with PEEK (211 and 58 MPa, respectively) than with PEKK (192 and 49 MPa), while the prosthetic framework showed the opposite behavior (59 MPa for PEEK and 67 MPa for PEKK). Conclusion The main differences related to the mechanical behavior of PEKK and PEEK frameworks for full-arch prostheses under the “all-on-four concept” were reflected in the prosthetic screw and the acrylic base. The superior shock absorbance of PEKK resulted in a lower stress concentration on the prosthetic screw and prosthetic base. This would clinically represent a lower fracture risk on the acrylic base and screw loosening. Conversely, lower stress concentration was observed on PEEK frameworks.

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Contact Stresses in a Fixed-Bearing Total Ankle Replacement

Foot & Ankle Orthopaedics ◽

10.1177/2473011417s000284 ◽

2017 ◽

Vol 2 (3) ◽

pp. 2473011417S0002 ◽

Cited By ~ 1

Author(s):

Nicoló Martinelli ◽

Silvia Baretta ◽

Alberto Bianchi Castagnone Prati ◽

Francesco Malerba ◽

Carlo Corrado Bonifacini ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stance Phase ◽

Gait Cycle ◽

Contact Stresses ◽

Von Mises Stress ◽

Third Generation ◽

Fixed Bearing ◽

Element Analysis ◽

Von Mises

Category: Ankle, Ankle Arthritis, Basic Sciences/Biologics Introduction/Purpose: Third-generation ankle implants with good clinical results continued to increase the popularity of total ankle arthroplasty (TAA) to address end-stage ankle osteoarthritis preserving joint movement. Newer TAA used fixed-bearing designs, with a theoretical increase of contact stresses leading to a higher polyethylene wear. The purpose of this study was to investigate the contact stresses in the polyethylene component of a new third-generation TAA, with a fixed-bearing design, using 3D finite element analysis. Methods: A three-dimensional finite element model was developed based on the Zimmer Trabecular Metal Total Ankle (ZTMTA) and a finite element analysis was employed to evaluate the contact pressure, contact area and Von Mises stress in the polyethylene articular surface in the stance phase of the gait cycle. Results: The peak values were found at the anterior regions of the articulating surface, where reached 19.8 MPa at 40% of gait cycle. The average contact pressure during the stance phase of gait was 6.9 MPa. The maximum von Mises stress of 14.1 MPa in the anterior section was reached at 40% of the gait cycle. For the central section the maximum von Mises stress of 10.8 MPa was reached at 37% of the gait cycle, whereas for posterior section the maximum of 5.4 MPa was reached at the end of the stance phase (60% of the gait cycle). Conclusion: Although, the average von Mises stress was less than 10 MPa, high peak pressure values were recorded. Advanced models to quantitatively estimate the wear are needed to assess polyethylene and metal component survivorship.

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