Lubricated sliding bearing with adjustment of the properties of the lubricant in certain parts of the bearing gap

A bearing device, comprising:

• a first surface and a second surface which are moveable relative to one another and which face one another, wherein the first surface and second surface are separated by a bearing gap filled with a lubricant, wherein the lubricant is a magnetorheological liquid or a lubricant having a controllable slip velocity,
• one or more supply inlets in the first or second surface, each supply inlet configured to supply the lubricant from a pressurized liquid source to the bearing gap, and
• one or more activators embedded in the first or second surface and configured to locally increase the viscosity of the lubricant or locally decrease the slip velocity of the lubricant in at least one obstruction zone in the bearing gap, thereby locally inhibiting a flow of the lubricant through the bearing gap in the obstruction zone,
• wherein the bearing gap comprises at least one non-obstruction zone in which the flow of the lubricant is not inhibited, wherein each non-obstruction zone surrounds the associated supply inlet,
• wherein a flow path of the lubricant through the bearing gap is defined, which flow path starts at the at least one supply inlet, extends along the at least one non-obstruction zone, traverses the obstruction zone and ends at a bearing gap end,
• wherein the first surface and the second surface are free of surface texturing, in particular in the form of a land and pad, and are smooth and continuous and are without any abrupt changes in a height of the bearing gap,
• wherein the at least one obstruction zone either by itself or in cooperation with other obstruction zones encloses the at least one non-obstruction zone,
• wherein the lubricant having an increased viscosity or decreased slip velocity in the obstruction zone acts as an obstruction of the flow path and either by itself or in cooperation with lubricant with increased viscosity or decreased slip velocity in other obstruction zones inhibits the lubricant from flowing out of the non-obstruction zone and flowing out of the bearing gap through the bearing gap end, thereby increasing a pressure of the lubricant in the non-obstruction zone to a level which is sufficient to carry a load on the bearing device while preventing contact between the first and second surface.

A hydrodynamic bearing device, comprising:

• a first bearing surface, and
• a second bearing surface which faces the first bearing surface, wherein the first and second bearing surface are configured to rotate relative to one another about a main rotation axis,
• a bearing gap defined between the first and second bearing surface, the bearing gap being filled with a lubricant, wherein the lubricant is a magnetorheological liquid or a lubricant having a controllable slip velocity,
• a plurality of activators embedded in the first or second bearing surface and configured to locally increase a viscosity of the lubricant or locally decrease the slip velocity in a plurality of obstruction zones, thereby inhibiting a flow of the lubricant through the bearing gap in each obstruction zone, and
• a plurality of non-obstruction zones in which the flow of the lubricant is not inhibited, wherein in a direction of relative movement between the first and second bearing surface the obstruction zones and non-obstruction zone are provided in turns, each non-obstruction zone being located upstream of an associated obstruction zone,
• wherein each obstruction zone has a curved or angular shape, wherein the curved or angular shape defines a top being directed downstream, wherein the obstruction zone is configured to cause, when the first and second surfaces move relative to one another, a local rise of a pressure of the lubricant within the bearing gap in the non-obstruction zone which is located upstream of each obstruction zone and in particular in a peak zone which is located directly upstream of each top by locally increasing the viscosity or locally decreasing the slip velocity in the obstruction zone and inhibiting the flow of the lubricant across each obstruction zone,
• wherein the bearing device is a tilting pad bearing device and comprises a plurality of tilting pads which are tiltable, wherein the first surface comprises a plurality of first surface sections, each first surface section being associated with a tilting pad, and wherein the bearing gap comprises a plurality of bearing gap sections, each bearing gap section associated with a tilting pad,
• wherein each first surface section is smooth and free of any surface texturing, and each individual bearing gap section between a tilting pad and the opposed second surface is free of any abrupt changes in the height of the bearing gap,
• wherein each first surface section comprises an obstruction zone having a curved or angular shape, wherein the curved or angular shape defines a top being directed downstream, wherein the obstruction zone is configured to cause, when the first and second surfaces move relative to one another, a local rise of a pressure of the lubricant within the bearing gap in the non-obstruction zone which is located upstream of each obstruction zone and in particular in a peak zone which is located directly upstream of each top by locally increasing the viscosity or locally decreasing the slip velocity in the obstruction zone and inhibiting the flow of the lubricant across each obstruction zone.