In the past three decades, it is very challenging for the researchers to design and development a best gas turbine engine component. Engine component has to face different operating conditions at different working environments. Nickel based superalloys are the best material to design turbine components. Inconel 718, Inconel 617, Hastelloy, Monel and Udimet are the common material used for turbine components. Directional solidification is one of the conventional casting routes followed to develop turbine blades. It is also reported that the raw materials are heat treated / age hardened to enrich the desired properties of the material implementation. Accordingly they are highly susceptible to mechanical and thermal stresses while operating. The hot section of the turbine components will experience repeated thermal stress. The halides in the combination of sulfur, chlorides and vanadate are deposited as molten salt on the surface of the turbine blade. On prolonged exposure the surface of the turbine blade starts to peel as an oxide scale. Microscopic images are the supportive results to compare the surface morphology after complete oxidation / corrosion studies. The spectroscopic results are useful to identify the elemental analysis over oxides formed. The predominant oxides observed are NiO, Cr2O3, Fe2O3 and NiCr2O4. These oxides are vulnerable on prolonged exposure and according to PB ratio the passivation are very less. In recent research, the invention on nickel based superalloys turbine blades produced through other advanced manufacturing process is also compared. A summary was made through comparing the conventional material and advanced materials performance of turbine blade material for high temperature performance.


Author(s):  
John D. Cyrus

The increasing emphasis on engine durability requires that an analytical capability be acquired to assess engine component lives during the conceptual/preliminary design phases. A generalized methodology has been developed to provide a fundamental understanding of the impact of engine design decisions, material selections, and a detailed consideration of engine usage for critical gas turbine engine components.


Author(s):  
Phillip A. Craig ◽  
David Godfrey

Through work in two U.S. Department of Energy cooperative programs with industry, the confidence level for utilization of ceramic composite SiC/SiC combustor liners has risen from a prototype curiosity to serious planning and addressing of hurdles for commercialization. One of the most significant hurdles for true commercialization is affordability of the ceramic composite combustor liners. To study the manufacturing costs for CFCC liners, a study was conducted to identify cost items and relationships. This report describes the effort, identifies the high impact areas of manufacturing costs, and recommends potential approaches to reducing the manufacturing costs.


JOM ◽  
2003 ◽  
Vol 55 (3) ◽  
pp. 27-31 ◽  
Author(s):  
Mei Ling Clemens ◽  
Allen Price ◽  
Richard S. Bellows

1975 ◽  
Vol 12 (4) ◽  
pp. 423-430
Author(s):  
R. A. Cundiff ◽  
R. H. Badgley ◽  
J. Reddecliff

1970 ◽  
Author(s):  
J. Grandcoing

Pilots of modern aircraft have had to be provided with minimal operations in engine handling and controlling in order to devote themselves mainly to aircraft handling. Helicopter design has increasingly used the turbine engine governing system not only to control engine operation, but also to maintain a constant rotor speed, to pre-set the maximum power available in case of need, and to protect the rotating assemblies against overspeeding. This paper reviews the general requirements to be met by the helicopter engine governor system in multi- and single-engined craft with turbo-shaft or free-turbine engines (with the engine governor in the free-turbine model either controlled by the rotor speed governor or used to control rotor speed. Since the governor system has come to be considered an essential component of the helicopter and no longer as an engine component, the system must participate in general operation of the helicopter, allowing maximum performance over the entire flight envelope while requiring only minimal action and monitoring by the pilot.


Sign in / Sign up

Export Citation Format

Share Document