Comprehensive analysis of fluid-film instability in journal bearings with mechanically indented textures

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F23%3APU150535" target="_blank" >RIV/00216305:26210/23:PU150535 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/49777513:23520/23:43967023

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0022460X2200637X" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0022460X2200637X</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jsv.2022.117454" target="_blank" >10.1016/j.jsv.2022.117454</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Comprehensive analysis of fluid-film instability in journal bearings with mechanically indented textures

Popis výsledku v původním jazyce

This paper theoretically and experimentally investigates the effects of textures produced by a mechanical indentation on the stability of journal bearings. The research primarily aims at lightly loaded journal bearings used, e.g. in vertical rotors and microturbines. The results show that textures located close to the minimum oil film thickness can noticeably improve the stability at low specific loads but have only a negligible effect at a specific load of 0.15 MPa. The texturing also impacts the bearing temperature, which is closely related to the bearing friction. Since the textured journal bearings are prone to the formation of cavities in the oil film, the paper also deals with computational methods. It is demonstrated that an accurate estimate of stability threshold requires very dense computational meshes, which are impractical for mass-conserving treatment of cavitation due to CPU requirements. Interestingly, errors due to non-conservation of mass are up to the same magnitude as uncertainties due to employed numerical algorithms. The results demonstrate that numerical results describing lightly-loaded textured journal bearings are very sensitive to the density of the computational mesh. Hence, the simplified cavitation treatment can be legitimate in applications where the CPU time is a concern, such as the optimisation, iterative algorithms and time-integration of equations of motion.

Název v anglickém jazyce

Comprehensive analysis of fluid-film instability in journal bearings with mechanically indented textures

Popis výsledku anglicky

This paper theoretically and experimentally investigates the effects of textures produced by a mechanical indentation on the stability of journal bearings. The research primarily aims at lightly loaded journal bearings used, e.g. in vertical rotors and microturbines. The results show that textures located close to the minimum oil film thickness can noticeably improve the stability at low specific loads but have only a negligible effect at a specific load of 0.15 MPa. The texturing also impacts the bearing temperature, which is closely related to the bearing friction. Since the textured journal bearings are prone to the formation of cavities in the oil film, the paper also deals with computational methods. It is demonstrated that an accurate estimate of stability threshold requires very dense computational meshes, which are impractical for mass-conserving treatment of cavitation due to CPU requirements. Interestingly, errors due to non-conservation of mass are up to the same magnitude as uncertainties due to employed numerical algorithms. The results demonstrate that numerical results describing lightly-loaded textured journal bearings are very sensitive to the density of the computational mesh. Hence, the simplified cavitation treatment can be legitimate in applications where the CPU time is a concern, such as the optimisation, iterative algorithms and time-integration of equations of motion.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20301 - Mechanical engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

JOURNAL OF SOUND AND VIBRATION

ISSN

0022-460X

e-ISSN

1095-8568

Svazek periodika

546

Číslo periodika v rámci svazku

03

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

22

Strana od-do

„“-„“

Kód UT WoS článku

000902165200003

EID výsledku v databázi Scopus

2-s2.0-85144068001