THROTTLE FOR TESTING OF COMPRESSORS Russian patent published in 2007 - IPC G01M15/02 

FIELD: the invention refers to the field of compressor engineering and for testing of compressors.

SUBSTANCE: in a ring channel formed by an external body and an inner body with flat sites fulfilled on them for stabilization of radial clearances and located in parallel to the axle of the throttle there are pair blades of a symmetrical aerodynamic profile turning towards each other with the axle of the turn displaced forward towards the flow of gas relatively to the center of pressure on the profile whose chord is equal B≥2πR/N (where R - a current radius, N- a number of blades). At that the even blades are displaced relatively the odd blades of each pair on an angle Δα=2π/N·(1-_B1/_B2)/(1+_B1/_B2),where _B1- the size of the part of the chord from the front edge of the blade to the axle of the turn, _B2 - the size of the part of the chord from the axle of the turn to the rear edge of the blade). At that the even and the odd blades of each pair have guiding drivers of the same length directed in different sides with pins radially located on their ball surfaces entering into the grooves of equidistant from the axles of the blades of the driving rings installed on rollers allowing the driving rings to travel in circumferential direction from the position corresponding to closed position of the blades of the throttle θ_1blad.oth.=0° to the position corresponding the to the position of the blades of the throttle θ_2blad.oth. = 90°+Δθ°, where Δθ° - an angle of setting the blades behind the meridional plane necessary for gas-dynamic damping of shocking loadings and nor allowing to the driving rings to travel in the axial direction due to limiting lugs located on the outward surface of the external body of the throttle. At that the both driving rings are rigidly connected between themselves with bridges, one or more of them at off-design turn of the driving rings enter into a contact with the stops installed on the outward surface of the external body of the throttle and the both driving rings are connected with the output rod of the driving mechanism pivotally fixed on the external body with the aid of an snapping into action on an exterior signal anti-surging arrangement having a cylinder pivotally fastened on the driving rings, a piston with a rod, a ring placed inside the cylinder from the side opposite to the position of the driving mechanism, channels for feeding and discharging compressed air from the cavity opposite to the cavity of the position of the spring. At that the squares of the open-flow areas of the discharging valve and of the electromagnetic valve installed after it is no less than 5 times more then the square of the passing section of channel connected with the system of the feeding of the working gas into the cylinder of the anti-surging arrangement.

EFFECT: the throttle ensures the construction of the compressor from long-term influencing of dynamic impacts and possible destruction of the construction at surging, at stalling oscillations of the blades of the compressor or in any other emergency situation.

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