Showing papers on "Axial compressor published in 1969"

The Response of Axial Flow Compressors to Intake Flow Distortion

Abstract: The response of a lift engine model compressor to inlet pressure distortion is studied in detail to determine the nature and extent of the critical area of spoiling. This is found to be a sector of width between 60 and 90 deg. On this basis a simple distortion index is proposed which implies that only the circumferential pressure gradients of a complex distortion pattern are significant. The “Parallel Compressor” model satisfactorily explains surge and this experience is related to different types of compressors and to complex spoiling patterns. Comments are made on the differences in behavior between compressors operating on rig test and in engines.Copyright © 1969 by ASME

Gas turbine power plant

Abstract: A TURBO-FAN POWER PLANT IS DISCLOSED IN WHICH THEY ARE TWO INDEPENDENT FANS IN THE FAN DUCT RESPECTIVELY DRIVEN BY A GAS GENERATOR AND AN INDEPENDENT FREE TURBINE. THE GAS GENERATOR INCLUDES IN AXIAL FLOW SERIES LOW, INTERMEDATE AND HIGH PRESSURE COMPRESSOR RESPECTIVELY DRIVINGLY INTERCONNECTED WITH HIGH, INTERMEDIATE AND LOW PRESSURE TURBINES, THE INTERMEDIATE PRESSURE TURBINE BEING DRIVING- LY CONNECTED TO THE UPSTREAM OR FRONT OF THE TWO FAN THE DRIVE ARRANGEMENT OF THE FANS AND THEIR AXIAL SPACING ENABLES THEM TO ROTATE AT RELATIVELY LOW SPEEDS AND SUB STANTALLY WITHOUT ANY WAKE INTERACTION THEREBETWEEN , WHEREBY THE OVERALL NOISE OF THE POWER PLANT IS REDUCED.

Reduction of sound in gas turbine engines

Abstract: The disclosure shows a representative axial flow compressor in the form of a fan employed in reaction type propulsive engines. The inlet guide vanes and the rotor blades of this fan are provided with slots lengthwise of the outer portions of their trailing edges. Pressurized air is discharged from these slots to minimize circumferential velocity gradients immediately downstream of the vanes and blades. By minimizing such velocity gradients, sound generated by the air entering the rotating blades and the outlet guide vanes is minimized.

Turbine engine having multistage compressor with interstage bleed air system

Abstract: A bleed system which provides air for other than combustion purposes in a gas turbine engine. Bleed air is diverted from a multistage axial flow compressor through a diffuser flow passageway formed in the casing of the compressor. The entrance to this bleed passageway is defined by an annular lip disposed, in an axial sense, between a row of stator vanes and a row of rotor blades.

Static pressure and velocity profiles in swirling incompressible tube flow

Abstract: The phenomenon of reversing axial flow in swirling incompressible flow through a tube has been investigated experimentally. The study was carried out in a 2 in. I.D. test section of plexiglass tubing 10 ft. long. The swirl was introduced by injection of the total fluid stream through two symmetric tangential inlets perpendicular to the tube. Measurements have been made with specially constructed stagnation and static pressure probes. Velocity and pressure profiles obtained for tests conducted at four Reynold's Numbers in one fixed geometrical configuration are presented and discussed in general terms. Swirl decay rate is characterized in a plot of weighted tangential velocity/inlet velocity ratio versus distance along the test section from the inlets. A model presented by a previous investigator to explain the flow reversal phenomenon is discussed in the light of present work. Finally the data is used in an order of magnitude analysis to reduce the turbulent Navier-Stokes equation describing the flow to simpler (though still indeterminate) form.

Gas turbine support arrangement

Abstract: A SUPPORT ARRANGEMENT FOR AN AXIAL FLOW ELASTIC FLUID MACHINE COMPRISING, AFTER FINAL ASSEMBLY, TWO SUPPORT PLATES AND POSITIONED THEREBETWEEN A GIB KEY AND BLOCK ASSEMBLY. THE FLAT PLATES ARE FIXED IN THE VERTICAL AND LATERAL DIRECTIONS BUT ARE ALLOWED TO FLEX IN AN AXIAL DIRECTION WHEN THERMAL MOVEMENT OCCURS. THE GIB KEY IS FIXED IN THE AXIAL DIRECTION AND IS POSITIONED SO AS TO PROPORTION THE AXIAL MOVEMENT BETWEEN FORE AND AFT SUPPORT PLATES. IN THIS MANNER PROPER ALIGNMENT IS MAINTAINED BETWEEN THE GAS TURBINE SHAFT AND LOAD SHAFT. DURING SHIPMENT THE AFT SUPPORT PLATE IS REMOVED SO THAT THE BASE CAN TWIST WITHOUT IMPARTING A TORISIONAL MOMENT TO THE GAS TURBINE CASINGS.

Transonic buckets for axial flow turbines

Abstract: TURBINE BUCKET PROFILES FOR THE TRANSONIC FLUID FLOW REGION AT THE OUTER PORTIONS OF AXIAL FLOW STEAM TURBINE BUCKETS, THE PROFILES BEING CHARACTERIZED BY SUBSTANTIALLY FLAT PRESSURE AND SUCTION SIDES DIVERGING TOWARD THE TRAILING EDGE OVER THE MID-PORTION OF THE PROFILE, THE BUCKETS OVERLAPPING ONE ANOTHER AND SHAPED TO PROVIDE A TRANSONIC AND SUPERSONIC FLOW REGION BETWEEN BUCKETS.

Compressors for gas turbine engines

Abstract: 1280113 Centrifugal and axial-flow compressors; gas turbine engines AVCO CORP 30 June 1970 [4 Aug 1969] 31621/70 Headings F1C and F1G A compressor in or for a gas turbine engine comprises an axial-flow section 32, 46, Fig. 1, and a downstream, contra-rotating mixed-flow section 62. The axial-flow section discharges air at subsonic absolute velocity. The mixed-flow section has an inlet portion which is of substantially constant flow area and receives the air at supersonic relative velocity to thereby produce shock waves and reduce supersonic flow to subsonic, whereafter the air is radially accelerated and diffused in the outlet portion of the mixed-flow section. The impeller blades of the latter may be divided into an inlet row and and outlet row separated by a row of stator blades, Fig. 3 (not shown). Stator vanes (150), Fig. 8 (not shown), may be located immediately upstream of the mixed-flow section to equalize the relative velocity of the entering air over the radial extent of the annular flow duct. In the gas turbine engine shown, the compressed air is discharged through a diffuser 84 into combustion apparatus 18 comprising an annular series of cylindrical combustion units 90 which deliver hot gases into a duct 92. The latter discharges the gases through a full-admission inlet nozzle to drive turbine wheels 98, 114, which drive the respective compressor sections, and to either drive a further turbine wheel having an output shaft 30 or exhaust through a nozzle to produce propulsive thrust. Alternatively, the two compressor sections may be driven by a single turbine wheel via gearing. Sump housings 54, 72, 120 for the shaft bearings are each sealed at both ends by friction or labyrinth seal assemblies 60, 74, 106, 122.

Multistage compressor simulation applied to the prediction of axial flow instabilities

Abstract: Multistage turbocompressor simulation applied to performance prediction of axial flow instabilities

Gas turbine engine axial flow multistage compressor

Abstract: The invention concerns a gas turbine engine axial flow multistage compressor having a rotor member, and a plurality of platform elements each of which has rotor blade members mounted thereon and each of which is itself disposed radially outwardly of and spaced from the rotor member, the plurality of platform elements defining an annular platform member and the axially consecutive annular platform member of different stages of rotor blade members contacting each other to form a drumlike structure.

Combustion instability with finite Mach number flow and acoustic liners

Abstract: Small amplitude linear analysis of combustion instability with finite Mach number flow and acoustic liners

A Comparison of the Performance of Three Model Axial Flow Turbines Tested under Both Steady and Pulse Flow Conditions

Abstract: Three turbines, covering a range of reaction of +20 per cent to − 10 per cent at their blade roots, have been tested under both steady and ‘pulse flow’ conditions in order to assess their degree of suitability for turbo-charger application.The results have been analysed in a way which enables efficiencies to be plotted against a mean non-dimensional blade speed irrespective of the level of pulsation. This method of presentation enables the results to be used directly for design purposes and in matching calculations. Thus the efficiency penalty due to pulse flow, the effect of pulse flow on the choice of turbine size, and the preferred degree of reaction under pulse flow may be assessed.For the present tests the range of variation in gas speed under pulsing conditions is thought to compare in severity with that produced when a single turbocharger is connected to three cylinders of a large two-stroke marine engine. For this case the design having the highest degree of reaction is shown to give an efficiency...

Programs for Computation of Velocities and Streamlines on a Blade-to-Blade Surface of a Turbomachine

Abstract: This paper describes Fortran programs that give the solution to the two-dimensional, subsonic, nonviscous flow problem on a blade-to-blade surface of revolution of a turbomachine. Flow may be axial, radial, or mixed. There may be a change in stream channel thickness in the through-flow direction. Either single, tandem, or slotted blades may be handled as well as blade rows with splitter vanes. Also, small regions may be magnified to give more detail where desired, such as around a leading or trailing edge or through a slot. The method is based on a finite difference solution of the stream function equations. Numerical examples are shown to illustrate the type of blades which can be analyzed, and to show results which can be obtained. Results are compared with experimental data.Copyright © 1969 by ASME

Low loss ventilation for salient pole machines

Abstract: A VENTILATION ARRANGEMENT FOR A DYNAMOELECTRIC MACHINE HAVING A ROTOR INCLUDING SALIENT POLE MEMBERS. STRUCTURE IS PROVIDED FOR SUBSTANTIALLY INCREASING COOLING EFFICIENCY AND REDUCING WINDAGE LOOSES IN THE MACHINE, THE STRUCTURE COMPRISING MEANS FOR DIRECTING A COOLING GASEOUS FLUID AXIALLY OF THE ROTOR BETWEEN THE SALIENT POLES FROM ONE END OF THE ROTOR TO THE OTHER, AND MEANS FOR BRIDGING THE INTERPOLAR SPACE IN ORDER TO PREVENT A VORTEX OF THE FLUID FROM DEVELOPING BETWEEN ADJACENT POLES, AND FOR OTHERWISE RESTRICTING THE CROSS-SECTIONAL AREA FOR AXIAL FLOW OF THE COOLING FLUID TO INCREASE THE AXIAL VELOCITY THEREOF.

Single-stage evaluation of highly-loaded high-Mach-number compressor stages

Abstract: Aerodynamical and mechanical single stage evaluation of highly loaded, high Mach number compressor stages

Effect of rotor tip clearance on the performance of a 5-inch single stage axial flow turbine

Abstract: Turbine efficiency decreased linearly with increasing rotor tip clearance. Static efficiency decreased 20 percent (0. 79 to 0. 63) as rotor tip clearance was increased from 1. 2 to 8. 0 percent of passage height. Rotor exit flow survey data are presented in addition to performance data. Comparison of data with three reference turbines substantiated the results obtained and indicated that rotor tip clearance effects are larger for a reaction turbine than for an impulse turbine. EFFECT OF ROTOR TIP CLEARANCE ON THE PERFORMANCE OF A 5-INCH SINGLE-STAGE AXIAL-FLOW TURBINE by Donald E. Holeski and Samuel M. Futral, Jr. Lewis Research Center

Pressure Drop Measurements of the Flow through Eccentric Cylinders with Rotating Inner Cylinders

Abstract: We previously investigated the pressure drop in an annulus with a rotating inner cylinder under fully developed conditions and reported that there is a noticeable increase in axial resistance associated with the onset of Taylor vortices for laminar flow of axial-flow Reynolds number above 100. On the other hand, in the case with no axial flow, it has been reported that the flow between eccentric cylinders with a rotating inner cylinder is more stable to the disturbance of Taylor vortex type than the flow between concentric cylinders. However there is no investigation of axial resistance connected with the development of Taylor vortices in the flow between eccentric rotating cylinders with axial flow. We measured the pressure drop in the eccentric annulus with a rotating inner cylinder under fully developed conditions, using water and glycerine-water solutions. And in this paper the relation between pressure drop and a few parameters, such as rotating Reynolds number, axial-flow Reynolds number, eccentricity ratio and clearance ratio, is investigated experimentally in connection with the development of Taylor vortices.

Compressible fluid turbine

Abstract: Centripetal blades of a compressible fluid turbine project into a scroll-like steam induction passage so that their tips lie at or near the tangential centerline of the passage inlet when each blade tip is disposed in a plane normal to such centerline. A pressure reducing valve in the inlet to the steam induction passage converts steam pressure into kinetic energy and is adjusted to produce a velocity of steam at the inlet which is substantially greater than the peripheral velocity of the blade. There is very little reaction effect of the steam on the centripetal blades as the steam is directed radially inwardly and then axially in opposite directions to axial flow portions of the turbine and, consequently, the efficiency of the turbine is increased.

Compact fluid compressor

Abstract: A regenerative compressor in accordance with the invention described herein comprises a stator and a rotor coaxial therewith to form a motor. Concentric to the motor and between its ends is a compressor chamber having inlet and exhaust openings. A compressor wheel is mounted on the rotor and projects into the compressor chamber for providing a high compression output in a limited space.

Paper 1: Relation between Blade Row Spacing and Potential Flow Interaction Effects in Turbomachines:

Abstract: This paper develops a simple relationship between distance upstream and downstream of a row of blades and the velocity disturbances created by the passage of those blades. The relationship is compared with values obtained by numerical computation and measurement in an experimental axial flow compressor rig. The magnitude of vibration exciting forces and/or noise radiation sources due to potential flow interaction on a stationary row of blades is directly related to the magnitude of these velocity fluctuations. The analysis is therefore a basis (a) for estimating the inter-row spacings for a turbomachine such that potential flow interactions are reduced below the levels of other forms of interaction, and (b) of translating practical experience of noise and/or vibration excitation in existing machines to give reliable predictions for future designs.It is found that while potential flow interaction effects drop rapidly with increasing blade row spacing for low-speed machines, this is not the case for high sp...

Method of making compressor or turbine rotor or stator blades

Abstract: A METHOD OF MAKING AN ANNULUS OF BLADES FOR A GAS TURBINE ENGINE IS PROPOSED IN WHICH BLADE ROW IS FORMED FROM AN ANNULAR ARRAY OF PIECES, EACH COMPRISING A BLADE FLANK, AN INTERCONNECTING PORTION, AND AN OPPOSING FLANK OF AN ADJACENT BLADE. THE PIECES ARE MADE FROM FIBER REINFORCED MATERIAL AND PREFERRED METHOD OF MANUFACTURE OF THE PIECES USING FILAMENT WINDING TECHNIQUES ARE UTILIZED IN MAKING THE INDIVIDUAL PIECES.

Experimental evaluation of outer case blowing or bleeding of single stage axial flow compressor. Part 5 - Performance of plain casing insert configuration with distorted inlet flow

Abstract: Outer case bleeding or blowing effects on casing insert of single stage axial flow compressor with distorted inlet flow

Dump bleed system for the compressor of a gas turbine engine

Abstract: A DUMP BLEED SYSTEM FOR THE COMPRESSOR OF A GAS TURBINE ENGINE. THE CASING OF THE AXIAL FLOW COMPRESSOR IS PROVIDED WITH A CIRCUMFERENTIAL BLEED PORT OF UNIQUE CONFIGURATION. THIS PORT IS SELECTIVELY CLOSED BY A RING HAVING TAPERED SEALING SURFACES ENGAGED ON OPPOSITE SIDES OF THE PORT DISCHARGE.

Blade mount and stall control for vane axial compressors

Abstract: Radial compressor blades are adjustably and releasably mounted on the impeller hub. A set of rigid bayonet formations defines the blade axial position positively at all pitch angles. A set of flexible detent formations defines the pitch angle effectively positively during operation, but yieldably for manual adjustment between discrete values. A positive lock must be released for blade removal. Especially at low pitch angles, the compressor is stabilized against stall by aperturing one or more blades.