Abstract: This report investigates the kinetics of lubricant molecules in the HAMR air bearing to understand the initiation and growth of PFPE contamination on the head surface. The collisions with the air bearing induce three forces—drag, thermophoresis, and lift. Of these, we find that lift forces are negligible. Then, a sensitivity analysis of t...
This doctoral research focuses on lubricants behavior in highly loaded lubricated contacts (pressure > 1 GPa), or EHD (elastohydrodynamic) contacts, a vital aspect of engineering and industry. Under such high load, the friction coefficient (= tangential force/normal load) measured in these contacts may display a plateau regime at medium to high sli...
Published in Heliyon
A complete study is presented on the response of thermoplastic and thermoplastic composite materials for bearing cages of bogie trains for rail applications to aging conditions in presence of lubricants. Glass Fiber reinforced Polyamaide 66 (GF PA66) is proposed as commercial material already used in the field while Polyether Ether Ketone (PEEK) is...
Tato bakalářská práce se zabývá vibrodiagnostikou a tribodiagnostikou s aplikací na obráběcí stroje. Teoretická část práce se věnuje vibrodiagnostice a tribodiagnostice, zahrnující příčiny vibrací, sledování opotřebení strojů a degradaci maziv. Následuje praktická část, která se zaměřuje na konkrétní obráběcí stroje. Měření vibrací je provedeno pom...
Published in Human fertility (Cambridge, England)
Couples trying to conceive or providing samples for Assisted Reproductive Technologies (ART) are advised against the use of lubricant-gels due to the risk of sperm-toxicity. However, gels now exist which are specifically formulated to help couples conceive but without consensus on their toxicity relative to non-specialist products. This study teste...
This thesis presents a quantitative approach to elastohydrodynamic (EHD) friction prediction, based on a combination of experimental rheometry data and molecular dynamics (MD) simulations. The approach is applied to two fluids of different natures: a lubricant squalane (SQ) and a traction-like fluid benzyl benzoate (BB). The Newtonian viscosity of ...
[ES] El siguiente trabajo final de grado está destinado al análisis, diseño y fabricación de un sistema de transmisión (multi‐stage) para el molinete de una cosechadora agrícola, con el fin de mostrar claramente los elementos constituyentes, así como el funcionamiento de los mismos. Durante el desarrollo, se estudiarán las variables relevantes de l...
Published in Environmental research
2,6-Di-tert-butyl-hydroxytotulene (BHT) is an additive commonly used in the manufacturing of lubricants to improve their antioxidant properties. However, in this study, we found that BHT affects the biodegradation of bio-lubricants by influencing the microbial community during the degradation of bio-lubricants. Specifically, BHT was found to reduce...
Published in Mikrochimica acta
A fast and efficient method was developed for obtaining europium(III)-doped surface-modified carbon dots with a hydrophobic coating. This surface functionalization improved the dispersibility of the nanoparticles in non-polar media, as well as modified the accessibility of water molecules to the europium ions. These two features allowed studying th...
The fluid that separates the contacting elements in many industrial applications is often a mixture of oil and operating fluids. This work aims to provide a better understanding of lubrication with mixtures in elastohydrodynamic contacts in order to anticipate appropriate lubrication system performance. The oil/refrigerant mixture and the oil/water...
