Finite Element Analysis of a Pipe Junction With a Thermal Sleeve Subject to Thermal and Pressure Transient Events

This paper describes the results of a Finite Element Analysis (FEA) of a pipe junction consisting of a thermal sleeve subject to rapid temperature changes. The purpose of the analysis was to utilise derived Computational Fluid Dynamic (CFD) temperatures to calculate stresses on the pressure boundary and thermal sleeve of a pipe junction. Several transient events were modelled and analysed. Work was then carried out in accordance with the relevant articles of the ASME Boiler and Pressure Vessel Code, Section III, sub-section NB. Work included, design, hydrotest, Level A (including fatigue) and simplified elastic plastic assessments, however not presented within this paper. The likely fracture performance of the pressure boundary was also investigated, however are also not presented within this paper.

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A Smart Stent for Monitoring Eventual Restenosis: Computational Fluid Dynamic and Finite Element Analysis in Descending Thoracic Aorta

Machines ◽

10.3390/machines8040081 ◽

2020 ◽

Vol 8 (4) ◽

pp. 81

Author(s):

Betsy D. M. Chaparro-Rico ◽

Fabio Sebastiano ◽

Daniele Cafolla

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Flow Velocity ◽

Computational Fluid Dynamic ◽

Stent Implantation ◽

Fluid Dynamic ◽

Pressure Sensors ◽

Metal Mesh ◽

Element Analysis ◽

Mesh Structure

Even though scientific studies of smart stents are extensive, current smart stents focus on pressure sensors. This paper presents a novel implantable biocompatible smart stent for monitoring eventual restenosis. The device is comprised of a metal mesh structure, a biocompatible and adaptable envelope, and pair-operated ultrasonic sensors for restenosis monitoring through flow velocity. Aside from continuous monitoring of restenosis post-implantation, it is also important to evaluate whether the stent design itself causes complications such as restenosis or thrombosis. Therefore, computational fluid dynamic (CFD) analysis before and after stent implantation were carried out as well as finite element analysis (FEA). The proposed smart stent was put in the descending thoracic section of a virtually reconstructed aorta that comes from a computed tomography (CT) scan. Blood flow velocity showed that after stent implantation, there is not liquid retention or vortex generation. In addition, blood pressures after stent implantation were within the normal blood pressure values. The stress and the factor of safety (FOS) analysis showed that the stress values reached by the stent are very far from the yield strength limit of the materials and that the stent is stiff enough to support the applied loads exported from the CFD results.

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Performance analysis of a semi-active suspension system using coupled CFD-FEA based non-parametric modeling of low capacity shear mode monotube MR damper

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407018765899 ◽

2018 ◽

Vol 233 (5) ◽

pp. 1214-1231 ◽

Cited By ~ 4

Author(s):

Gurubasavaraju Tharehalli Mata ◽

Hemantha Kumar ◽

Arun Mahalingam

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Magnetic Flux ◽

Computational Fluid Dynamic ◽

Fluid Dynamic ◽

Parametric Modeling ◽

Magnetorheological Damper ◽

Shear Mode ◽

Element Analysis ◽

Non Parametric

In this work, an approach for formulation of a non-parametric-based polynomial representative model of magnetorheological damper through coupled computational fluid dynamics and finite element analysis is presented. Using this, the performance of a quarter car suspension subjected to random road excitation is estimated. Initially, prepared MR fluid is characterized to obtain a relationship between the field-dependent shear stress and magnetic flux density. The amount of magnetic flux induced in the shear gap of magnetorheological damper is computed using finite element analysis. The computed magnetic field is used in the computational fluid dynamic analysis to calculate the maximum force induced under specified frequency, displacement and applied current using ANSYS CFX software. Experiments have been conducted to verify the credibility of the results obtained from computational analysis, and a comparative study has been made. From the comparison, it was found that a good agreement exists between experimental and computed results. Furthermore, the influence of fluid flow gap length and frequency on the induced force of the damper is investigated using the computational methods (finite element analysis and computational fluid dynamic) for various values. This proposed approach would serve in the preliminary design for estimation of magnetorheological damper dynamic performance in semi-active suspensions computationally prior to experimental analysis.

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