DE1551173B1 - DEVICE FOR VIBRATION DAMPING ON FREE-STANDING BLADES OF FLOW MACHINERY - Google Patents

Claims (1)

The invention relates to a device for swimmable wires in this known device in the middle attenuation of the gas flow on free-standing blades and disrupt it by turning them into vortex flow machines, with the cover plates of the formations, which in turn are un-blades loosely arranged attenuators. controllable blade vibrations result Such a facility is in the UK 5 may have. Also are the damping wires Patent 623,525. In the known tempera device, which is particularly strong in turbine rotors the attenuators are exposed to the effects of the deck door. plates loosely overlapping, in each case the joint gaps Through the combination of features according to the invention bridging between the individual cover plates, tion is a device for vibration damping U-shaped clasps formed in cross-section, their io on free-standing blades of flow radial external leg ends given in axial drawing machines, their dampers neither tion are bent towards each other. The damping we are exposed to temperature effects, nor the The effect is that the clasps interfere with the flow of fluid. Another advantage due to the device according to the invention occurring when the rotor rotates, it follows that Centrifugal forces are pressed radially outward, so 15, the circumferential bores to accommodate the that their webs on the radially inner surfaces of damping wires accommodating shroud front Place cover plates. Cracks also act as sealing strips, which The damping clasps of the known device reduce the leakage losses in a manner known per se, that is, on the radially outer edge of the annular one. A further advantage of the gas ducts according to the invention, and therefore particularly in the case of turbine devices, is that the blade parts are exposed to the incoming strong temperature effects. Do not cut individual blades through circumferential bores, because the bent leg ends of the damping wires are weakened. Finally, clasp radially outside over the cover plates, it is a great advantage that there is a broken blade between them, for example in the blade leg ends radially outside of the annular blade area, which is segmented by centrifugal force to the outside Circumferential gaps, pressed, broken blade part only the resistance, which on the one hand has to overcome the efficiency of the streamline position of the damping wire, leakage gaps that deteriorate the machine for the flow before it can get into the turbine housing,
Forming means and on the other hand to the harmonic. An exemplary embodiment of the see excitation of blade vibrations occasion ₃₀ invention can be described with reference to the drawing. ben. It shows The task at hand is, in the case of devices for FIG. 1, a schematic, perspective partial Vibration damping of the all-around view of a gas turbine rotor blade and
common design on the one hand the attenuators of Fig. 2 a schematic, partially sectioned direct action of the fluid to ₃₅ partial development of the shroud part one with removal of the barrel, on the other hand to avoid leakage losses according to FIG. 1 equipped turbine rotor, and finally the excitation of blade speed The blading shown by the partial development that escapes via leaks is also included To prevent fluids. Cover plates 2 provided, in turn at their radially This object is achieved according to the invention by ₄₀ outer sides each with three known per se, the combination of the following features solved: sealing strips running in the circumferential direction of the rotor3, : 4 and 5 are equipped, which are parallel to the rotor a) On the cover plates are radially outside in the direction of spacing from one another. The two, Sealing strips running in the circumferential direction are each arranged in the vicinity of the axially outer cover plate; 45 sealing strips 3 and 5 on the edges are thickened b) the damping elements are ring-shaped damping wires with surrounding wires running in the circumferential direction of the rotor, which are provided in the circumferential bores of the catch bores 6. These circumferential bore sealing strips are loosely inserted. gen 6 form with respect to the runner, respectively coherent around the entire circumference of the runner From the British patent specification 989 260 it is 50 channels running around within the cover plates, Knows, cover plates of free-standing rotor blades through these channels are damping wires 7 to flow machines carried out radially outside with in circumferential, the flexible, the blade vibrations to provide direction running sealing strips and form counteracting damping rings. These so to prevent that outside the annular damping rings can either turn into a flow channel Leak gaps arise. 55 individual damping wire sections be divided or In the Swiss patent specification 302 674, however, closed rings are formed,
a device for the vibration damping of free-standing rotor blades of turbomachines
described, in which ring-shaped damping wires are used as damping members, which are in scope 60 patent claim:
the bores of the blades are loosely inserted,
the damping effect in turn arises from the fact that these damping wires are pressed against the cover plates of the stanchions on the radially outer inner surfaces of these circumferential drilling machines by the device for vibration damping on centrifugal forces occurring when the rotor is rotating on free-standing blades of flow. Apart from the fact that the blades, loosely arranged damping elements, blade blades are weakened by the named circumferential drilling, characterized by the combination, the damping features are as follows: a) On the cover plates (2) there are sealing strips extending radially on the outside in the circumferential direction (3, 4, 5) arranged; b) the damping members are ring-shaped damping wires (7) which are inserted into circumferential bores (6) of the sealing strips (3, 5) are loosely inserted. 1 sheet of drawings