Observing the thermodynamic effects in cavitating flow by IR thermography

Petkovšek, Martin (author), Dular, Matevž (author)

When dealing with liquid flows, where operating temperature gets close to the liquid critical temperature, cavitation cannot be assumed as an isothermal phenomenon. Due to the relatively high density of vapor, the thermodynamic effect (decrease of temperature in the bulk liquid due to latent heat flow) becomes considerable and should not be neglected. For applications like pumping cryogenic fuel and oxidizer in liquid propulsion space launchers, consideration of the thermodynamic effect is essential - consequently the physical understanding of the phenomenon and its direct experimental observation has a great value. This study presents temperature measurements in a cavitating flow on a simple convergent-divergent constriction by infrared (IR) thermography. Developed cavitating flow of hot water (-100 °C) was evaluated by high-speed IR thermography and compared with conventional high-speed visualization, at different operating conditions with the velocity range at the nozzle throat between 9.6 and 20.6 m/s and inlet pressure range between 143 and 263 kPa. Temperature depression near the nozzle throat - near the leading edge of cavitation was measured in a range up to [vartriangle]T = 0.5 K. This confirms the presence of the thermodynamic effects by cavitation phenomenon and it is in agreement with its theory. In the study, average temperature fields, fields of temperature standard deviation and time-resolved temperatures, are presented and discussed. In addition, statistical analysis between temperature drop and cavitation flow characteristics is shown.

• Language: English
• Keywords: thermodynamic effect, cavitation, temperature measurements, thermography, convergent-divergent nozzle
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Author Accepted Manuscript
• Article acceptance date: 02.07.2017
• Publication date: 01.11.2017
• Year: 2017
• Number of pages: Str. 450-460
• Numbering: Vol. 88
• PID: 20.500.12556/RUL-126453
• UDC: 532.528(045)
• ISSN on article: 0894-1777
• DOI: 10.1016/j.expthermflusci.2017.07.001
• COBISS.SI-ID: 15578139
• Publication date in RUL: 22.04.2021

Record is a part of a journal

• Title: Experimental thermal and fluid science
• Shortened title: Exp. therm. fluid sci.
• Publisher: Elsevier
• ISSN: 0894-1777
• COBISS.SI-ID: 170523

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.
• Licensing start date: 01.11.2017

Secondary language

• Language: Slovenian
• Keywords: termodinamski učinek, kavitacija, meritve temperature, termografija

Projects

• Funder: EC - European Commission
• Funding programme: European Space Agency (ESA)
• Name: Cavitation in Thermosensible Fluids