Numerical investigation of wall pressure fluctuations downstream of concentric and eccentric blunt stenosis models

Date

2020-01-01

Author

Ozden, Kamil
Sert, Cüneyt
Yazıcıoğlu, Yiğit

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

165
views

0
downloads

Pressure fluctuations that cause acoustic radiation from vessel models with concentric and eccentric blunt stenoses are investigated. Large eddy simulations of non-pulsatile flow condition are performed using OpenFOAM. Calculated amplitude and spatial-spectral distribution of acoustic pressures at the post-stenotic region are compared with previous experimental and theoretical results. It is found that increasing the Reynolds number does not change the location of the maximum root mean square wall pressure, but causes a general increase in the spectrum level, although the change in the shape of the spectrum is not significant. On the contrary, compared to the concentric model at the same Reynolds number, eccentricity leads to an increase both at the distance of the location of the maximum root mean square wall pressure from the stenosis exit and the spectrum level. This effect becomes more distinct when radial eccentricity of the stenosis increases. Both the flow rate and the eccentricity of the stenosis shape are evaluated to be clinically important parameters in diagnosing stenosis.

Subject Keywords

Mechanical Engineering, General Medicine

URI

https://hdl.handle.net/11511/39800

Journal

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE

DOI

https://doi.org/10.1177/0954411919884167

Collections

Department of Mechanical Engineering, Article

Suggestions

OpenMETU
Core

Experimental investigation and modeling of dropwise condensation on a horizontal gold coated tube / Serdar, Orhan; Yamalı, Cemil; Department of Mechanical Engineering (2004) The phenomenon dropwise condensation on a horizontal gold coated tube is investigated by both analytical and experimental methods in this study. A computer program is prepared to calculate the dropwise condensation heat transfer rate on the horizontal gold coated tube. An experimental setup was also manufactured to measure the dropwise condensation heat transfer rate. The effects of flow rate, temperature of cooling water and also steam to wall temperature difference have been analytically investigated by u...
Experimental study of solid propellant combustion instability Çekiç, Ayça; Ulaş, Abdullah; Department of Mechanical Engineering (2005) In this study, experimental investigation of solid propellant combustion instability using an end burning T-Burner setup is performed. For this purpose, a T-Burner setup is designed, analyzed, constructed and tested with all its sub components. T-Burner setup constructed is mainly composed of a base part, a control panel and the T-Burner itself. Combustion chamber, pressure stabilization mechanism, pressurization system, measurement instruments and data acquisition systems form the T-Burner. Pressure stabil...
Numerical and experimental investigation of forced filmwise condensation over bundle of tubes in the presence of noncondensable gases Ramadan, Abdul-Ghani M; Yamalı, Cemil; Department of Mechanical Engineering (2006) The problem of the forced film condensation heat transfer of pure steam and steam-air mixture flowing downward a tier of horizontal cylinders is investigated numerically and experimentally. Liquid and vapor-air mixture boundary layers were solved by an implicit finite difference scheme. The effects of the free stream non-condensable gas (air) concentration, free stream velocity (Reynolds number), cylinder diameter, temperature difference and angle of inclination on the condensation heat transfer are analyze...
Transient dynamic response of viscoelastic cylinders enclosed in filament wound cylindrical composites Şen, Özge; Turhan, Doğan; Department of Engineering Sciences (2005) In this study, transient dynamic response of viscoelastic cylinders enclosed in filament wound cylindrical composites is investigated. Thermal effects, in addition to mechanical effects, are taken into consideration. A generalized thermoelasticity theory which incorporates the temperature rate among the constitutive variables and is referred to as temperature-rate dependent thermoelasticity theory is employed. This theory predicts finite heat propagation speeds. The body considered in this thesis consists o...
Mechanical fatique and life estimation analysis of printed circuit board components Genç, Cem; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2006) In this thesis, vibration induced fatigue life analysis of axial leaded Tantalum & Aluminum capacitors, PDIP and SM capacitors mounted on the printed circuit boards are performed. This approach requires the finite element model, material properties and dynamic characteristics of the PCB. The young modulus of the PCB material is obtained from 3 point bending tests, resonance frequencies are obtained from modal tests and transmissibility’s of the PCB are obtained from transmissibility tests which are used as ...

Citation Formats

K. Ozden, C. Sert, and Y. Yazıcıoğlu, “Numerical investigation of wall pressure fluctuations downstream of concentric and eccentric blunt stenosis models,” PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE, pp. 48–60, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39800.