Polimer-Viskoelastik Malzemeli Boru Hatlarındaki Eğilme Dalgalarının Dispersiyonu

Year 2019, Volume: 21 Issue: 62, 577 - 586, 21.05.2019

Tarık Koçal

https://doi.org/10.21205/deufmd.2019216221

Abstract

Bu makale çalışmasında korozyondan
korunmak amacıyla viskoelastik malzemeden yapılmış deniz aşırı geçicek petrol
boru hatlarının tahribatsız muayenelerinde kullanılmak üzere eğilme
dalgalarının boru üzerindeki yayılımından bahsedilmektedir. Araştırmalar parçalı
homojen cisim modeli kapsamında viskoelastisite teorisinin kesin denklemleri
kullanılarak yapıldı. Nümerik araştırmalarda kullanılmak üzere fraksiyonel
eksponansiyel operatörler aracılığıyla borunun bünye denklemleri çıkarıldı.
Dispersif sönüm durumu için dalganın yayılımının birinci mod sonuçları elde
edildi. Elde edilen sonuçlara göre boru malzemesinin viskoelastisitesinin
artmasıyla eğilme dalgalarının yayılım hızında düşüşe neden olduğu saptandı.
Aynı zamanda boru iç çapı ile borunun cidar kalınlığı arasındaki oranın dalga
yayılımında önemli bir rol aldığı gözlemlenmiştir.

Keywords

Eğilme dalgaları, Reolojik Parametre, Viskoelastik Malzeme, Dalga Dispersiyonu

Dispersion of Flexural Waves in Polymer-Viscoelastic Material Pipelines

Abstract

This
paper is about propagating of the bending waves on the pipes which are used in
non-destructive inspection of offshore oil pipelines made from viscoelastic
materials to protect from corrosion. The investigations were made using exact
equations of the viscoelasticity theory in the context of a piecewise homogeneous
body model. The constitutive equations of the pipe were obtained through
fractional exponential operators for use in numerical investigations. For the
dispersive attenuation cases, the first mode results of the waveguide
propagation were obtained. According to the results obtained, it was found that
the increase of the viscoelasticity of the pipe material caused the decrease of
the propagation velocity of the bending waves. At the same time, it is observed
that the ratio between the pipe inner diameter and the wall thickness of the
pipe plays an important role in wave propagation.

Keywords

Bending (flexural) waves, Reolojical Parameter, Viscoelastic Material, Wave Dispersion

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