This paper presents a theoretical analysis of two-dimensional grease flow through an asymmetric discontinuity. The behaviour of the fluid is described using NavierStokes equations, numerically solved by the finite-element method. The ELFI program was used for this purpose. For this type of discontinuity, the velocity profile in the lubricant film, the shape and the dimensions of the stagnant core, the flow capacity, and the pressure distribution have been obtained. The results are useful in the design of bearings, if one considers the discontinuities in the carrying region as orifices, canals, or pockets for lubrication. Abstract two-dimensional flow, grease, finite-element analysis, asymmetric discontinuity, bearings Keywords Nomenclature A a DII D"= z,h/pU, non-dimensional parameter characteristic of the lubricant film strain rate tensor second invariant of the strain rate tensor characteristic parameter for the second invariant of the strain rate tensor film thickness characteristic film thicknesses for the discontinuity non-dimensional characteristic film thickness for the discontinuity characteristic lengths of the discontinuity pressure shear rate tensor second invariant of the shear rate tensor Lubrication Science 15-2, February 2003. (1 5 ) 163 ISSN 0954-0075 $1 0.00 + $1 0.00 (2077/0203) 164 Alexandru V. Radulescu, Dominique Bonneau, and Mohammed Hajjam: A theoretical study of two-dimensional grease flow in regions with discontinuities U u, v, w velocity of the lower moving surface velocities corresponding to the Ox, Oy, and Oz axes -U -W

Carbonated water baths represent a method used for the prevention and treatment of cardiovascular diseases in some spa resorts in Romania. Carbonated mineral waters are the result of the filtration of depth waters through volcanic soils that contain carbon dioxide. The most important effect is the direct effect of carbon dioxide, which is absorbed through the skin, with an absorption coefficient of 30-35 ml/min/sqm body surface area. An excitation of vascular receptors and a dilation of dermal papillae, responsible for skin erythema, occur. The effects of the carbonated water bath on the cardiovascular system are the following: decrease of peripheral resistance by the direct action of carbon dioxide on arterioles and arteriovenous anastomoses; increase of both systolic and diastolic cardiac output, not by central mechanism as in the case of hot baths, but initially, by passive peripheral vasodilation, without increased venous return; subsequently, by accumulation in the cutaneous venous system, venous return towards the right heart will be increased, with a higher diastolic filling and a higher stroke volume. Carbonated water baths increase arteriolar blood flow in the skin, the vasodilator effect being directly proportional to the carbon dioxide concentration in the mineral bath. The effect of external carbonated water treatment is based on mechanical and thermal action, as well as on the chemical properties of carbon dioxide, its influence being either local or postabsorptive. Carbonated water baths are a therapeutic method that is also used in the treatment facilities of the Baile Tusnad spa resort, under the supervision of qualified medical experts, in a pleasant environment close to nature.

The purpose of this paper is a comparison between rapeseed oil and soybean oil, regarding their rheological and tribological properties. Tests were performed on a Brookfield viscometer with cone-plate geometry, having the following test parameters: test type -shear rate imposed, shear rate (100...2000 s -1 ), temperature values between 20 °C and 75 °C. In parallel, there were proceed tribological tests on a four ball machine, for three speeds (1200, 1500 and 1800 rpm). The results of the tests highlight the better rheologial and tribological behavior of the rapeseed oil, thus it could be recommended in tribological applications.

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The paper presents a simplified method for the analytical calculus of a grease‐lubricated infinitely large Rayleigh step bearing. The principal problem of the grease flow through a Rayleigh step bearing is the shape of the stagnant core in the step region. This shape is determined using Navier‐Stokes equations resolved by the finite method element. The theoretical results are compared with those obtained experimentally by visualisation of the grease flow using the reflecting tracer method. The conclusion of the simplified method is that a Rayleigh step bearing lubricated with grease is equivalent to one lubricated with oil, but with a different configuration of the convergent interstice.