Modelling of fatigue due to thermal mixing by using a spectrum method

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Abstract

Turbulent mixing of cold and hot fluids can lead to high-cycle thermal fatigue in T-junctions, but modelling of the thermal load induced to the structure is challenging. The spectrum method has been recently proposed as an efficient modelling method, which uses a theoretical turbulence spectrum to represent the fluctuating thermal load. In this work, further development and application of the method is presented. Estimation of the frequency of the largest-scale temperature fluctuations is considered in particular, as this is an essential input parameter for the model spectrum. The method is applied to a T-junction including a mixer pipe and a high temperature difference that induces significant buoyancy effects. The frequency scale of the fluctuations is determined for the flow case based on temperature spectra obtained from a Computational Fluid Dynamics (CFD) simulation. A formula for the frequency scale is proposed, which can be used in approximating the frequency scale for other flow conditions. Fatigue and crack growth analysis of the T-junction wall are carried out by using the spectrum method, and the results are compared with those obtained with sinusoidal and CFD temperature loads. The results indicate improvement in accuracy over the highly simplified sinusoidal method.

Original languageEnglish
Title of host publicationProceedings of the ASME 2018 Pressure Vessels and Piping Conference
Subtitle of host publicationDesign and Analysis
PublisherAmerican Society of Mechanical Engineers ASME
Number of pages10
Volume3A
ISBN (Electronic)978-0-7918-5162-3
DOIs
Publication statusPublished - 2018
MoE publication typeNot Eligible
EventASME 2018 Pressure Vessels and Piping Conference, PVP2018 - Hotel Hilton, Prague, Czech Republic
Duration: 15 Jul 201820 Jul 2018
Conference number: 52

Conference

ConferenceASME 2018 Pressure Vessels and Piping Conference, PVP2018
Abbreviated titlePVP2018
CountryCzech Republic
CityPrague
Period15/07/1820/07/18

Fingerprint

Fatigue of materials
Thermal load
Computational fluid dynamics
Temperature scales
Thermal fatigue
Buoyancy
Temperature
Crack propagation
Turbulence
Pipe
Fluids
Computer simulation
Hot Temperature

Cite this

Timperi, A. (2018). Modelling of fatigue due to thermal mixing by using a spectrum method. In Proceedings of the ASME 2018 Pressure Vessels and Piping Conference: Design and Analysis (Vol. 3A). [ PVP2018-84398] American Society of Mechanical Engineers ASME. https://doi.org/10.1115/PVP2018-84398
Timperi, Antti. / Modelling of fatigue due to thermal mixing by using a spectrum method. Proceedings of the ASME 2018 Pressure Vessels and Piping Conference: Design and Analysis. Vol. 3A American Society of Mechanical Engineers ASME, 2018.
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Timperi, A 2018, Modelling of fatigue due to thermal mixing by using a spectrum method. in Proceedings of the ASME 2018 Pressure Vessels and Piping Conference: Design and Analysis. vol. 3A, PVP2018-84398, American Society of Mechanical Engineers ASME, ASME 2018 Pressure Vessels and Piping Conference, PVP2018, Prague, Czech Republic, 15/07/18. https://doi.org/10.1115/PVP2018-84398

Modelling of fatigue due to thermal mixing by using a spectrum method. / Timperi, Antti.

Proceedings of the ASME 2018 Pressure Vessels and Piping Conference: Design and Analysis. Vol. 3A American Society of Mechanical Engineers ASME, 2018. PVP2018-84398.

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

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Timperi A. Modelling of fatigue due to thermal mixing by using a spectrum method. In Proceedings of the ASME 2018 Pressure Vessels and Piping Conference: Design and Analysis. Vol. 3A. American Society of Mechanical Engineers ASME. 2018. PVP2018-84398 https://doi.org/10.1115/PVP2018-84398