19 results about "Squeeze film" patented technology

The application belongs to the field of gear transmission system squeeze film damper damping, especially relates to a kind of gear squeeze film damper damping quick calculation method and system, obtains the structural parameter of squeeze film damper, carries out velocity calculation and constructs the Reynolds equation of squeeze film damper oil film pressure;Based on half-step center finite difference method, the Reynolds equation is solved, and the oil film distribution pressure of oil film damper is obtained;Based on oil film distribution pressure, the oil film counterforce of oil film damper is calculated using double integral algorithm.Compared with the classical short bearing approximate solution and long bearing approximate solution, its use range is wide, and compared with super relaxation iteration method, its calculation efficiency is high.Make it can be used in gear dynamics model to carry out damping analysis.When solving fluid Reynolds equation by finite difference method, only the working condition with regular boundary condition can be processed.Based on variational principle and Galerkin method, a new more general finite element method is proposed to calculate the oil film counterforce of SFD.

A squeeze film damper assembly for a turbine engine includes an annular bearing support and an annular damper housing. The annular bearing support includes an inner support segment and an outer support segment located radially outward of the inner support segment. The inner support segment and the outer support segment are spaced apart to define a support channel therebetween. The annular damper housing is at least partially received in the support channel to define an inner damping chamber and an outer damping chamber, the inner damping chamber being radially inward of the outer damping chamber, the inner damping chamber and the outer damping chamber each capable of being filled with an amount of lubricant to provide a squeeze film damper at the inner damping chamber, the outer damping chamber, or both.

The invention relates to a variable-clearance extrusion oil film damper based on an axial stepped oil film ring, belongs to the technical field of rotor vibration control, and solves one of the problems that damping adjustment of a rotor supporting structure in the prior art needs repeated disassembly, the test accuracy is low and the consistency is poor. A stepped oil film ring is arranged on the inner wall face of the oil film outer ring, and a plurality of annular step faces with different depths are machined in the axial direction. A damper oil inlet hole and a damper oil outlet hole which are through are formed in the annular step surface; the oil film outer ring sleeves the outer side of the positioning reference part to form an oil film gap; oil is sealed in the oil film gap to form an annular oil film; the axial positions of the oil film outer ring and the positioning reference part are adjustable; annular step surfaces with different depths are switched to be matched with the positioning reference component to form annular oil films with different thicknesses, and different damping gears can be switched. Quick switching of damping gears is achieved by adjusting axial positioning of the oil film inner ring.

The invention relates to the technical field of aero-engines, and discloses a squeeze film damper and rotating shaft mounting assembly and an aero-engine rotor. The squeeze film damper is used for a multi-fulcrum rotor with a centering function. The squeeze film damper and rotating shaft mounting assembly comprises a rotating shaft, a bearing, a bearing mounting assembly, a sealing ring, an oil film gap and a lubricating oil passage. An oil film gap is defined by the bearing outer ring, the bearing installation assembly and the sealing ring, the bearing installation assembly forms a lubricating oil passage communicating the outside with the oil film gap, and external lubricating oil can enter the oil film gap through the lubricating oil passage to form an extrusion oil film. According to the squeeze film damper and rotating shaft installation assembly, a centering elastic support is abandoned, the structure is simplified, the weight is reduced, and disassembly and assembly are convenient; the oil film gap is integrated into an enclosed structure of the bearing installation assembly, the bearing outer ring of the bearing and the sealing ring, redundant parts are omitted, the overall structure is further simplified, and the space occupied by installation is reduced.

This technology enables stable, high-speed rotation of the impeller in multi-stage centrifugal compressors for hydrogen applications. [Solution] The multi-stage centrifugal compressor for hydrogen comprises a rotating shaft, a plurality of impellers through which the rotating shaft is inserted and which rotate integrally with the rotating shaft, a casing housing the rotating shaft and the plurality of impellers, and journal bearings positioned at both ends of the rotating shaft to support the rotating shaft in the casing, and compresses hydrogen gas in multiple stages with the plurality of impellers. The plurality of impellers are closed impellers made of aluminum alloy with hydrogen embrittlement resistance. The journal bearing is a squeeze film damper bearing having a bearing portion that supports the rotating shaft and a squeeze film damper portion positioned between the bearing portion and the casing.

The invention discloses a squeeze film damper based on a one-way valve oil supply structure, belongs to the technical field of structural design of squeeze film dampers of aero-engines, and aims to solve the problems that periodic high-pressure backflow and low-pressure cavitation can be generated when a traditional squeeze film damper works. The extrusion oil film damper comprises an outer sleeve, an outer ring and a mouse cage inner ring, the mouse cage inner ring is coaxially sleeved with the outer sleeve and the outer ring in sequence from outside to inside, two one-way valve oil supply units are installed on the outer sleeve, and the two one-way valve oil supply units are orthogonally arranged; external oil sequentially flows through the outer sleeve and the outer ring through the two one-way valve oil supply units and enters the oil film area of the outer ring and the inner ring of the mouse cage, and the oil film damper is extruded to prevent internal high-pressure lubricating oil from flowing back through the one-way valve oil supply units. The damping structure is mainly used as a damping structure of a shafting mechanism in an aero-engine.

This invention belongs to the field of sliding bearing technology, and relates to a piezoelectrically actuated actively squeezed oil film damping tilting pad bearing and a method for controlling the squeezed effect based on it. The bearing includes a housing, a bearing body, multiple tilting pads, a preload mechanism, an active adjustment assembly, and a detachable wedge-shaped centering mechanism. The housing has an oil reservoir, and a squeezed oil film thickness layer is formed between the bearing body and the housing. The tilting pads contact the bearing body via spherical supports. The preload mechanism provides preload force, and the piezoelectric ceramic in the active adjustment assembly finely adjusts the squeezed damping effect through radial extension and retraction. The preload screw has a hollow channel for the lead wire to pass through, and the wedge-shaped centering mechanism ensures uniform oil film gap during initial assembly. This invention integrates piezoelectric actuation and squeezed oil film damping, combined with its advanced control algorithm, to actively regulate the squeezed effect, improve rotor system stability, reduce wear, and adapt to variable operating conditions.

The application provides a design method of an extrusion oil film damper, which comprises the following steps: S1, starting to design the extrusion oil film damper, determining the value range of an oil film shaft diameter, an oil film width and a target value of damping; S2, determining the value range of an oil film radius gap; S3, selecting an oil film oil supply mode, obtaining the values of the oil film width, the oil film radius gap and the damping, and making a relationship diagram among the oil film width, the oil film radius gap and the damping; S4, selecting appropriate oil film width and oil film radius gap, so that the value of the damping is close to the target value; and S5, outputting a design result. The design method of the extrusion oil film damper can reasonably consider the influence of the piston ring end sealing on the damping, meanwhile, the influence of the oil supply mode on the damping can be considered, and the value range of the influence coefficient is given, the design method is simple and practical, and has engineering application value.

A squeeze film damper assembly (100) for a compressor (12) includes a damper sleeve (112) configured to be disposed about a rotor shaft (72) of the compressor (12). The damper sleeve (112) includes a pressure dam recess (166) formed in an inner circumference (145) of the damper sleeve (112). The pressure dam recess (166) is configured to receive a flow of lubricant (24) and pressurize the flow of lubricant (24) via rotation of the rotor shaft (72). The damper sleeve (112) includes an outlet passage (142) extending from the pressure dam recess (166) to an outer circumference (134) of the damper sleeve (122). The squeeze film damper assembly (100) also includes a bearing housing (110) disposed about the damper sleeve (112) to form a damper gap (116) extending between the outer circumference (134) of the damper sleeve (112) and the bearing housing (110). The damper gap (116) is fluidly coupled to the outlet passage (142) and configured to receive the flow of lubricant (24) from the pressure dam recess (166).

An aircraft engine, has: a shaft rotatable about a central axis; a bearing housing extending around the shaft and defining a bearing cavity; a bearing located within the bearing cavity, the bearing rotatably supporting the shaft, the bearing having rolling members disposed radially between an inner race engaged to the shaft and an outer race; an outer sleeve secured to and extending around the outer race of the bearing, a radially-inner face of the outer sleeve abutting a radially-outer face of the outer race; and a squeeze film damper including an annulus defined radially between the outer sleeve and a portion of the bearing housing and axially between seals, the annulus having a damping fluid in the annulus.

The utility model provides an on-line profile laminating tool, and belongs to the technical field of profile laminating. Comprising a support used for being installed between an extruder and a traction machine, a plurality of first rollers used for supporting profiles are arranged on the support at intervals in the conveying direction of the profiles, the first rollers are rotationally arranged on the support, an unwinding device used for unwinding a film layer is arranged on the support, and a guide shaft is rotationally arranged on the support and located below the unwinding device; a conveying space used for allowing a profile to penetrate through is formed between the guide shaft and the first roller, a gluing mechanism used for coating one face of a film layer with glue is arranged on the portion, between the unwinding device and the guide shaft, of the support, and the movable end of the film layer bypasses the guide shaft and then adheres to the top of the profile. The support is provided with a first extrusion assembly used for extruding the film layer so that the film layer can be attached to the profile. And the effect of improving the production efficiency is achieved.

An aircraft engine is described which has: a shaft; a bearing housing extending around the shaft and defining a bearing cavity; a bearing within the bearing cavity and supporting the shaft; a squeeze film damper having an annulus receiving a damping fluid; and a controller. The controller is configured to: operate the squeeze film damper in a first regime in which a speed of the damping fluid in the annulus is less than a speed of sound in the damping fluid; determine that the shaft is subjected to vibrations having an amplitude greater than an amplitude threshold; and upon determining that the amplitude of the vibrations is greater than the amplitude threshold, operate the squeeze film damper in a second regime in which the speed of the damping fluid in the annulus is greater than the speed of sound in the damping fluid.

An squeeze oil film damper, planetary reducer and gear transmission turbofan engine for improving the situation of load imbalance between planetary gears; the squeeze oil film damper comprises a shaft member and a hole member, the shaft member and the hole member cooperate to form an annular gap, the squeeze oil film damper further comprises an oil film bushing and a sealing ring arranged in the annular gap, the oil film bushing and the sealing ring define an oil film gap; the radially outer ring of the oil film bushing cooperates with the radially inner ring of the hole member to define the radial dimension of the oil film gap; the sealing ring defines the axial dimension of the oil film gap, at least two of the oil film gaps are distributed along the axial direction for axial sealing; the oil film gap is used for internal oil filling to form an oil film layer for radial floating support, the oil film bushing is radially deformable to expand the radial deformable dimension of the oil film layer.

A gas turbine engine includes a turbine section and a compressor section. The turbine section and the compressor section each include rotors, with a first turbine rotor driving a first compressor rotor through at least one shaft. At least one bearing compartment includes static structure and at least one bearing supports the at least one shaft for rotation about a rotational axis. A damper chamber is defined radially between an outer surface of the at least one bearing and an inner surface of the static structure. The damper chamber is defined by axially spaced seals received in seal ring grooves. A lubricant supply supplies lubricant into the damper chamber, and into the seal ring grooves. The lubricant supply includes at least one of an inner passage on an opposed radial side of the seal ring grooves relative to the damper chamber and / or an axially aligned passage directly radially outward of each of the seal ring groove or a cutout in a supporting structure supporting the at least one bearing and over a limited circumferential extent, and extending to connect the seal ring grooves.

This application belongs to the field of engine design technology, specifically relating to a method and apparatus for evaluating the vibration reduction effect of an aero-engine extrusion film damper. The method includes: firstly, acquiring rotor vibration data in the initial equilibrium and unbalanced states when assembling the extrusion film damper and process oil distribution sleeve, and calculating the unbalance sensitivity of the damper; then, acquiring vibration data in the initial equilibrium and unbalanced states when only the process oil distribution sleeve is installed, and determining the unbalance sensitivity in the original state; finally, comparing the difference between the two sensitivities to quantify the damper's vibration reduction performance. This application can accurately and efficiently test and evaluate the vibration reduction effect of the spring-loaded damper, is easy to implement in engineering, and saves costs.

Provided are an extrusion oil film damper, an oil film length adjusting system, and the like. The extrusion oil film damper comprises an inner ring, a fixing member, and a sliding member. The inner ring provides a shaft hole. The fixing member is fixed on the outer surface of the first end of the inner ring. The sliding member is opposite to the fixing member and is arranged on the outer surface of the second end of the inner ring, and defines an annular oil film layer with the inner ring. The sliding member is arranged to be movable along the axial direction of the inner ring, so as to increase or shorten the length of the annular oil film layer, and further adjust the oil film length. The oil film length adjusting system is provided. The extrusion oil film damper can conveniently and effectively directly adjust the oil film length, so as to achieve the effect of actively controlling the damping.

The application discloses a test device for simulating the structure of a non-centering extrusion oil film damper, which comprises a mandrel, a positioning force transmission rod, a spring rotating component, a pulling cylinder, an intermediate top cylinder, a stop ring, a spring ring, a bushing and the like. By adjusting the height of the intermediate top cylinder, the pulling force of the spring rotating component on the mandrel is changed, the dynamic eccentricity ratio of the extrusion oil film damper under different rotating speeds is simulated, and the constant axial pre-tightening force is applied to the non-centering extrusion oil film damper by the stop ring, the spring ring and the bushing, so that the axial positioning purpose is achieved. The device has a simple structure and can solve the dynamic test problem of the non-centering extrusion oil film damper caused by the rotor gravity and the initial axial pre-tightening force.

This multistage centrifugal compressor for hydrogen comprises: a rotary shaft; a plurality of impellers through which the rotary shaft is passed and which rotate integrally with the rotary shaft; a casing which houses the rotary shaft and the plurality of impellers; and journal bearings which are disposed at both ends of the rotary shaft and which cause the rotary shaft to be supported by the casing. The multistage centrifugal compressor compresses hydrogen gas in multiple stages by means of the plurality of impellers. The plurality of impellers are closed type impellers made of an aluminum alloy having hydrogen embrittlement resistance. The journal bearings are squeeze film damper bearings that each have: a bearing part for supporting the rotary shaft; and a squeeze film damper part disposed between the bearing part and the casing.

The invention discloses a gas turbine squeeze film damper rigidity measuring device, and relates to the technical field of performance testing of gas turbine rotor system matching parts. The method solves the problems that the measurement precision is restricted by the frequency measurement accuracy in the existing indirect measurement method for speculating the stiffness of the squeeze film damper by measuring the vibration frequency, and errors exist between the obtained comprehensive stiffness and the actually required stiffness of the rotor bearing position. A supporting tool fixes an extrusion oil film damper, a loading tool simulates the assembly relation between a rotor bearing and the extrusion oil film damper, one end of a lever is hinged to a hinge support, the other end of the lever bears the acting force of a probe of a loading sliding platform, and a loading guide rail restrains the movement direction of the loading sliding platform. The displacement measurement module carries out displacement detection corresponding to the bearing installation position. According to the invention, load amplification is realized through the lever principle, the actual rigidity of the squeeze film damper can be accurately obtained by adopting a direct loading and direct displacement measurement mode, and the installation and centering precision of a rotor is guaranteed.