scholarly journals The Contribution of Metallic and Ceramic Coatings to Gas Turbine Engines

Author(s):  
R. E. Barnhart

Metallic and ceramic coatings enhance the quality of today’s gas turbine engines by enabling them to run longer and by increasing their reliability and efficiency of operation. Coatings give design engineers more latitude in their choice of materials for high-performance applications. Discussed here are the characteristics of coatings produced by three different means: detonation-gun process, plasma process, and diffusion process. By considering the following three parameters: (a) the nature of wear and corrosion problems in gas turbine engines, (b) the results of coated components in commercial service, and (c) the cost savings attributable to coatings, we can develop guidelines for even more effective use of coatings in the future.

1976 ◽  
Vol 98 (4) ◽  
pp. 619-625
Author(s):  
K. H. Pech ◽  
N. L. Downing

Fuel pumps and metering systems are becoming more complex and expensive to meet the high performance requirements of advanced gas turbine engines. A simple, inlet throttled, centrifugal pump integrated with a retracting vane starting element provides the potential for a reliable, high performance design capable of reducing the cost, weight, and temperature rise of the fuel system. This paper presents the results of recent efforts to develop the retracting vane element and to integrate it with a vapor core centrifugal pump in order to meet the fuel performance and functional requirements of an advanced gas turbine main fuel pump.


Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4214
Author(s):  
Kranthi Kumar Maniam ◽  
Shiladitya Paul

The increased demand for high performance gas turbine engines has resulted in a continuous search for new base materials and coatings. With the significant developments in nickel-based superalloys, the quest for developments related to thermal barrier coating (TBC) systems is increasing rapidly and is considered a key area of research. Of key importance are the processing routes that can provide the required coating properties when applied on engine components with complex shapes, such as turbine vanes, blades, etc. Despite significant research and development in the coating systems, the scope of electrodeposition as a potential alternative to the conventional methods of producing bond coats has only been realised to a limited extent. Additionally, their effectiveness in prolonging the alloys’ lifetime is not well understood. This review summarises the work on electrodeposition as a coating development method for application in high temperature alloys for gas turbine engines and discusses the progress in the coatings that combine electrodeposition and other processes to achieve desired bond coats. The overall aim of this review is to emphasise the role of electrodeposition as a potential cost-effective alternative to produce bond coats. Besides, the developments in the electrodeposition of aluminium from ionic liquids for potential applications in gas turbines and the nuclear sector, as well as cost considerations and future challenges, are reviewed with the crucial raw materials’ current and future savings scenarios in mind.


Author(s):  
J. M. Lane

While the radial in-flow turbine has consistently demonstrated its capability as a high-performance component for small gas turbine engines, its use has been relegated to lower turbine-inlet-temperature cycles due to insurmountable problems with respect to the manufacturing of radial turbine rotors with internal cooling passages. These cycle temperature limitations are not consistent with modern trends toward higher-performance, fuel-conservative engines. This paper presents the results of several Army-sponsored programs, the first of which addresses the performance potential for the high-temperature radial turbine. The subsequent discussion presents the results of two successful programs dedicated to developing fabrication techniques for internally cooled radial turbines, including mechanical integrity testing. Finally, future near-term capabilities are projected.


Author(s):  
A.D. Williams ◽  
J.L. Humphries

Abstract Over recent years, with the drive for new higher power, higher efficiency Gas Turbine engines, manufacturers have had to look at new alloys and new coating techniques to achieve and support the industry requirements. Repair technology has therefore had to keep pace with the OEM advances and much research and development has been undertaken in developing new repair processes. Many of the alloys now used are directionally solidified or single crystal, which until now have been deemed irreparable by traditional welding techniques. Recent developments in the use of lasers have not only rendered these alloys salvageable but have also reduced the overall repair time and therefore the cost. This paper looks at the use of laser technology as a repair process for gas turbine components, touching briefly on laser cutting and drilling but concentrating mainly on laser powder feed welding and its applications.


2021 ◽  
Vol 20 (3) ◽  
pp. 152-159
Author(s):  
A. M. Faramazyan ◽  
S. S. Remchukov ◽  
I. V. Demidyuk

The application of casting technologies in the production of parts and assemblies of small-size gas turbine engines is justified in the paper. The technology of vacuum casting in gypsum molds was tested during the production of an experimental centrifugal compressor of a small-size gas turbine engine. On the basis of a 3D model of the designed centrifugal compressor, computational studies of vacuum casting were carried out and rational parameters of the technological process were determined. Prototypes of the developed centrifugal compressor of a small-size gas turbine engine were made. The results of calculations and the performed technological experiment confirmed the fill rate of the gating form and the absence of short pour. The distribution of shrinkage porosity and cavities corresponds to the design values and is concentrated in the central part of the casting that is subjected to subsequent machining. The area of the blades, disc and sleeve is formed without defects. The use of casting technologies in the production of parts and assemblies of small-size gas turbine engines assures the required quality with a comparatively low price of the finished product, making it possible to achieve the balance between the cost of the technology and the quality of the product made according to this technology.


Author(s):  
Michael J. Roemer ◽  
Carl S. Byington ◽  
Gregory J. Kacprzynski ◽  
George Vachtsevanos

The DoD has various vehicle platforms powered by high performance gas turbine engines that would benefit greatly from predictive health management technologies that can detect, isolate and assess remaining useful life of critical line replaceable units (LRUs) or subsystems. In order to meet these needs for next generation engines, dedicated prognostic algorithms must be developed that are capable of operating in an autonomous and real-time engine health management system software architecture that is distributed in nature. This envisioned prognostic and health management system should allow engine-level reasoners to have visibility and insight into the results of local diagnostic and prognostic technologies implemented down at the LRU and subsystem levels. To accomplish this effectively requires an integrated suite of prognostic technologies that can be applied to critical engine systems and can capture fault/failure mode propagation and interactions that occur in these systems, all the way up through the engine and eventually vehicle level. In the paper, the authors will present a generic set of selected prognostic algorithm approaches that can be applied to gas turbine engines, as well as provide an overview of the required reasoning architecture needed to integrate the prognostic information across the engine.


Author(s):  
Thomas B. Kenney

Presently, the typical gas turbine based power generator relies on a large, expensive skid system to provide lubrication to the bearings. These skids consist of a large number of expensive components, many of which require maintenance that drives operating cost and creates environmental hazards. A smart lube system based on recently developed technology enables dramatic simplification and cost reduction of the skid system and significantly reduces oil consumption along with the frequency and cost of maintenance. Such a system would take advantage of the availability of advanced pump system controls and fluid nozzle technology to drastically reduce the quantity of oil required, and the resultant heat rejection. As a result, the sizes of reservoir, cooler, filter and piping are greatly reduced. The cost of components, support equipment and maintenance activities will also be reduced to a fraction of their present values.


Author(s):  
R. J. Bratton ◽  
S. K. Lau ◽  
C. A. Andersson ◽  
S. Y. Lee

Ceramic thermal barrier coatings are currently under active development in the U.S. for both aircraft and industrial/Utility gas turbine operation. These coating systems generally consist of an oxidation-corrosion resistant metal bond coat of the MCrAlY type and either a single thick layer ceramic overcoat or a graded ceramic/MCrAlY overcoat. This paper summarizes studies conducted on the high-temperature corrosion resistance of ZrO2 · Y2O3, ZrO2 · MgO and Ca2SiO4 plasma sprayed coatings that are candidates for use as thermal barrier coatings in gas turbine engines. Coatings were evaluated in both atmospheric burner rig and pressurized passage tests using GT No. 2 fuel and that doped with corrosive impurities such as sodium, sulfur and vanadium. The test results showed that the coatings perform very well in the clean fuel pressurized passage tests as well as burner rig tests. With impure fuels, it was found that chemical reactions between the ceramic coatings and combustion gases/condensates played the critical role in coating degradation. This work was conducted for NASA and EPRI under contract NAS3-21377. Advanced coating development studies have also been conducted for NASA and DOE under contract DEN3-110.


Sign in / Sign up

Export Citation Format

Share Document