Procedure and results of the investigation of full-scale lock joints of blades of compressors of gas-turbine engines for fretting fatigue

1997 ◽  
Vol 29 (4) ◽  
pp. 424-430
Author(s):  
G. V. Tsybanev ◽  
Yu. S. Nalimov ◽  
O. N. Gerasimchuk
1967 ◽  
Vol 89 (2) ◽  
pp. 177-185 ◽  
Author(s):  
M. J. T. Smith ◽  
M. E. House

The noise sources from gas turbine engines are defined and their radiation patterns identified from test results. Examination of single-stage and full-scale engine compressor noise measurements leads to a prediction technique being evolved for inlet and efflux levels.


Author(s):  
R. K. Mishra ◽  
G. Gouda ◽  
B. S. Vedaprakash

A twin spool low bypass turbofan engine under development and its combustor in full-scale were tested independently at altitude conditions to establish the relight envelope of the engine. Demonstration of relight capability and defining its boundary are mandatory for military gas turbine engines and for single engine application in particular. The engine was first subjected to windmill to establish its windmilling characteristics. The full engine was then tested for light-off in an altitude test facility simulating windmilling conditions from 4 to 12 km altitude with flight Mach numbers from 0.2 to 1.0. The relight boundary is defined based on the successful light-off points achieved from engine tests. Similar tests were carried out on the full-scale combustion chamber in a stand-alone mode simulating altitude conditions at engine flame-out. The combustor test has defined the light-off and lean blow out limits of the at each point on the relight boundary. The information of fuel-air ratio at light-off and blow-out is very useful in setting the engine fuel schedule for altitude operation and relight. In this paper an attempt is made to highlight various tests carried out on engine and its combustor to define the relight boundary of the engine. The paper also emphasizes the experience of combustor development and associated problems in meeting the relight challenges of military engines. These problems include the necessity of higher fuel-air ratio at high altitudes, the role of additional localized fuel injection through start-up atomizers, and effect of single igniter on relight characteristics. The relight envelope demonstrated by the engine is very satisfactory to meet the first flight requirement where the flight mission generally concentrate in the zone of 0.6 to 0.8 Mach and altitude does not exceed 10 to 12 km. Combustor and atomizer modification is needed to improve relight performance and to shift the boundary to further left.


Author(s):  
D. Christensen ◽  
P. Cantin ◽  
D. Gutz ◽  
P. N. Szucs ◽  
A. R. Wadia ◽  
...  

Rig and engine test processes and in-flight operation and safety for modern gas turbine engines can be greatly improved with the development of accurate on-line measurement to gauge the aerodynamic stability level for fans and compressors. This paper describes the development and application of a robust real time algorithm for gauging fan/compressor aerodynamic stability level using over-the-rotor dynamic pressure sensors. This real time scheme computes a correlation measure through signal multiplication and integration. The algorithm uses the existing speed signal from the engine control for cycle synchronization. The algorithm is simple and is implemented on a portable computer to facilitate rapid realtime implementation on different experimental platforms as demonstrated both on a full-scale high-speed compressor rig and on an advanced aircraft engine. In the multi-stage advanced compressor rig test, the compressor was moved toward stall at constant speed by closing a discharge valve. The stability management system was able to detect an impending stall and trigger opening of the valve so as to avoid compressor surge. In the full-scale engine test, the engine was configured with a one-per-rev distortion screen and transients were run with a significant amount of fuel enrichment to facilitate stall. Test data from a series of continuous rapid transients run in the engine test showed that in all cases the stability management system was able to detect an impending stall and manipulated the enrichment part of the fuel schedule to provide stall free transients.


Author(s):  
J. S. Fear

The use of “broad-specification” fuels in aircraft gas turbine engines can be a significant factor in offsetting anticipated shortages of current-specification jet fuel in the latter part of the century. The changes in fuel properties accompanying the use of broad-specification fuels will tend to cause numerous emissions, performance, and durability problems in currently-designed combustion systems. The NASA Broad-Specification Fuels Combustion Technology Program is a contracted effort to evolve and demonstrate the technology required to utilize broad-specification fuels in current and next generation commercial Conventional Takeoff and Landing (CTOL) aircraft engines, and to verify this technology in full-scale engine tests in 1983. The program consists of three phases: Combustor Concept Screening, Combustor Optimization Testing, and Engine Verification Testing.


2008 ◽  
Vol 130 (3) ◽  
Author(s):  
D. Christensen ◽  
P. Cantin ◽  
D. Gutz ◽  
P. N. Szucs ◽  
A. R. Wadia ◽  
...  

Rig and engine test processes and in-flight operation and safety for modern gas turbine engines can be greatly improved with the development of accurate on-line measurement to gauge the aerodynamic stability level for fans and compressors. This paper describes the development and application of a robust real-time algorithm for gauging fan/compressor aerodynamic stability level using over-the-rotor dynamic pressure sensors. This real-time scheme computes a correlation measure through signal multiplication and integration. The algorithm uses the existing speed signal from the engine control for cycle synchronization. The algorithm is simple and is implemented on a portable computer to facilitate rapid real-time implementation on different experimental platforms as demonstrated both on a full-scale high-speed compressor rig and on an advanced aircraft engine. In the multistage advanced compressor rig test, the compressor was moved toward stall at constant speed by closing a discharge valve. The stability management system was able to detect an impending stall and trigger opening of the valve so as to avoid compressor surge. In the full-scale engine test, the engine was configured with a one-per-revolution distortion screen and transients were run with a significant amount of fuel enrichment to facilitate stall. Test data from a series of continuous rapid transients run in the engine test showed that in all cases, the stability management system was able to detect an impending stall and manipulated the enrichment part of the fuel schedule to provide stall-free transients.


1997 ◽  
Vol 28 (7-8) ◽  
pp. 536-542
Author(s):  
A. A. Khalatov ◽  
I. S. Varganov

1988 ◽  
Author(s):  
James C. Birdsall ◽  
William J. Davies ◽  
Richard Dixon ◽  
Matthew J. Ivary ◽  
Gary A. Wigell

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