Optimiranje učinkovitosti elastokaloričnih materialov z mehanskim obremenjevanjem pri različnih temperaturah

Cerar, Jan (author), Klemenc, Jernej (mentor), Tušek, Jaka (comentor)

Magistrsko delo obravnava psevdoelastične zlitine, ki izkazujejo oblikovni spomin, za namen uporabe v elastokaloričnem hladilnem sistemu.Zaradi dobro dokumentiranih izboljšav učinkovitosti elastokaloričnega učinka z nateznim cikličnim obremenjevanjem se poraja vprašanje, ali je možno enake efekte doseči tudi s tlačnim obremenjevanjem, ki je veliko bolj ugodno z vidika trajne dinamične trdnosti.V nalogi je raziskan vpliv tlačnega funkcionalnega utrujanja na elastokalorični učinek. V prvem delu eksperimenta je bilo izvedenih 100 obremenitvenih ciklov na cevkah narejenih iz zlitine niklja in titana pri štirih različnih okoliških temperaturah. V drugem delu pa smo merili temperaturne spremembe materiala pri adiabatnih obremenitvenih ciklih in določili histerezno delo, hladilno in grelno energijo ter učinkovitost.

• Language: Slovenian
• Keywords: materiali z oblikovnim spominom martenzitna transformacija elastokalorični učinek psevdoelastičnost učinkovitost utrujanje
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [J. Cerar]
• Year: 2019
• Number of pages: XXIV, 64 str.
• PID: 20.500.12556/RUL-109724
• UDC: 620.178.37:536.7(043.2)
• COBISS.SI-ID: 16915739
• Publication date in RUL: 07.09.2019

CERAR, Jan, 2019, Optimiranje učinkovitosti elastokaloričnih materialov z mehanskim obremenjevanjem pri različnih temperaturah [online]. Master’s thesis. Ljubljana : J. Cerar. [Accessed 7 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=109724

Secondary language

• Language: English
• Title: Optimizing the effectiveness of elastocaloric materials by applicaton of mechanical load under various temperatures

Abstract

Masters thesis examines pseudoelastic alloys which exhibit shape memory effect, to be used in an elastocaloric cooling system. Due to well-documented improvements regarding elastocaloric effect efficiency with the help of cyclic tensional loading, a question poses itself, whether the same outcomes can be achieved by compressional loading which is significantly more favourable from the perspective of fatigue strength. Therefore the effects of compressional loading on elastocaloric effect are researched through this work. The first part of experimentation consists of cyclically loading tubes made from an alloy of nickel and titanium 100 times at four different ambient temperatures. In the second part, temperature change during adiabatic loading cycles is measured. In the end, hysteretic work and both heating and cooling energies are determined. Additionally, the coefficient of performance is calculated as a measure of efficiency.

• Keywords: shape memory materials martensitic transformation elastocaloric effect pseudoelasticity efficiency fatigue