Browsing by Author "Teodorescu, M."

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    Cavitation induced starvation for piston-ring/liner tribological conjunction.
    (Elsevier, 2011-04) Chong, William Woei Fong; Teodorescu, M.; Vaughan, Nicholas D.
    The study investigates the mechanism of ring-liner lubrication in the vicinity of the top and bottom dead centres of an internal combustion engine. Predicting lubricant transient behaviour is critical when the inlet reversal leads to thin films and inherent metal-to-metal interaction. It was found that the cavitation, which is located at the trailing edge of the contact before reversal, briefly survives after reversal as a confined bubble at the leading edge. This depletes the film promoting starvation. Several algorithms were compared. It is concluded that the lubricant film is thinner than initially thought.
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    A review of some tribo-dynamics phenomena from micro- to nano-scale conjunctions
    (Elsevier, 2009-12) Rahnejat, H.; Johns-Rahnejat, P. M.; Teodorescu, M.; Votsios, V.; Kushwaha, M.
    The paper provides some highlights in the developments of theories of lubrication and contact mechanics from early pioneering works of Reynolds and Hertz to the establishment of elastohydrodynamic phenomenon by Ertel and Grubin. Some historical discourse is made on the development of elastohydrodynamic theory in the past 6 decades, with particular attention paid to the contact of rolling element bearings. The steady miniaturisation of devices has led to progressively smaller contacts of individual features with lighter load share and diminishing gaps. The ultra-thin films are supported by interaction potentials that significantly deviate from bulk continuum behaviour of lubricating films, with insignificant contributions due to viscous–elastic nature of contacts. Using the same theme of rolling element contacts, the paper highlights the action of some of these dominant forces at close range.