scholarly journals The Formation of High Temperature Minerals From an Evaporite-Rich Dust in Gas Turbine Engine Ingestion Tests

2020 ◽  
Author(s):  
Jacob Elms ◽  
Alison Pawley ◽  
Nicholas Bojdo ◽  
Merren Jones ◽  
Rory Clarkson
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Operating Conditions ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Test Bed ◽  
Turbine Engine ◽  
Mineral Assemblages ◽  
Mineral Dusts ◽  
Engine Components

Abstract The ingestion of multi-mineral dusts by gas turbine engines during routine operations is a significant problem for engine manufacturers because of the damage caused to engine components and their protective thermal barrier coatings. A complete understanding of the reactions forming these deposits is limited by a lack of knowledge of compositions of ingested dusts and unknown engine conditions. Test bed engines can be dosed with dusts of known composition under controlled operating conditions, but past engine tests have used standardised test dusts that do not resemble the composition of the background dust in the operating regions. A new evaporiterich test dust was developed and used in a full engine ingestion test, designed to simulate operation in regions with evaporiterich geology, such as Doha or Dubai. Analysis of the engine deposits showed that mineral fractionation was present in the cooler, upstream sections of the engine. In the hotter, downstream sections, deposits contained new, high temperature phases formed by reaction of minerals in the test dust. The mineral assemblages in these deposits are similar to those found from previous analysis of service returns. Segregation of anhydrite from other high temperature phases in a deposit sample taken from a High Pressure Turbine blade suggests a relationship between temperature and sulfur content. This study highlights the potential for manipulating deposit chemistry to mitigate the damage caused in the downstream sections of gas turbine engines. The results of this study also suggest that the concentration of ingested dust in the inlet air may not be a significant contributing factor to deposit chemistry.

scholarly journals THE FORMATION OF HIGH TEMPERATURE MINERALS FROM AN EVAPORITE-RICH DUST IN GAS TURBINE ENGINE INGESTION TESTS

2021 ◽  
pp. 1-11
Author(s):  
Jacob Elms ◽  
Alison Pawley ◽  
Nicholas Bojdo ◽  
Merren Jones ◽  
Rory J. Clarkson
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Previous Analysis ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Complete Understanding ◽  
Turbine Engine ◽  
Mineral Assemblages ◽  
Mineral Dusts ◽  
Engine Components

Abstract The ingestion of multi-mineral dusts by gas turbine engines during routine operations is a significant problem for engine manufacturers because of the damage caused to engine components and their protective thermal barrier coatings. A complete understanding of the reactions forming these deposits is limited by a lack of knowledge of compositions of ingested dusts and unknown engine conditions. Past engine tests have used standardised test dusts that do not resemble the composition of the background dust in the operating regions. A new evaporite-rich test dust was developed and used in a full engine ingestion test, designed to simulate operation in regions with evaporite-rich geology, such as Doha or Dubai. Analysis of the engine deposits showed that mineral fractionation was present in the cooler, upstream sections of the engine. In the hotter, downstream sections, deposits contained new, high temperature phases formed by reaction of minerals in the test dust. The mineral assemblages in these deposits are similar to those found from previous analysis of service returns. Segregation of anhydrite from other high temperature phases in a deposit sample taken from a High Pressure Turbine blade suggests a relationship between temperature and sulfur content. This study highlights the potential for manipulating deposit chemistry to mitigate the damage caused in the downstream sections of gas turbine engines. The results of this study also suggest that the concentration of ingested dust in the inlet air may not be a significant contributing factor to deposit chemistry.

Ultra-High Temperature Compliant Foil Bearings: The Journey to 870°C and Application in Gas Turbine Engines — Experiment

2018 ◽  
Author(s):  
Hooshang Heshmat ◽  
James F. Walton ◽  
Brian D. Nicholson
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Operating Conditions ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Turbine Engine ◽  
Foil Bearings ◽  
Wide Range ◽  
The U.S ◽  
Ultra High Temperature

In this paper, the authors present the results of recent developments demonstrating that ultra-high temperature compliant foil bearings are suitable for application in a wide range of high temperature turbomachinery including gas turbine engines, supercritical CO2 power turbines and automotive turbochargers as supported by test data showing operation of foil bearings at temperatures to 870°C (1600°F). This work represents the culmination of efforts begun in 1987, when the U.S. Air Force established and led the government and industry collaborative Integrated High Performance Turbine Engine Technology (IHPTET) program. The stated goal of IHPTET was to deliver twice the propulsion capability of turbine engines in existence at that time. Following IHPTET, the Versatile Affordable Advanced Turbine Engines (VAATE) program further expanded on the original goals by including both versatility and affordability as key elements in advancing turbine engine technology. Achieving the stated performance goals would require significantly more extreme operating conditions including higher temperatures, pressures and speeds, which in turn would require bearings capable of sustaining temperatures in excess of 815°C (1500°F). Similarly, demands for more efficient automotive engines and power plants are subjecting the bearings in turbochargers and turbogenerators to more severe environments. Through the IHPTET and VAATE programs, the U.S. has made considerable research investments to advancing bearing technology, including active magnetic bearings, solid and vapor phase lubricated rolling element bearings, ceramic/hybrid ceramic bearings, powder lubricated bearings and compliant foil gas bearings. Thirty years after the IHPTET component goal of developing a bearing capable of sustained operation at temperatures above 540°C and potentially as high as 815°C (1500°F) recent testing has demonstrated achievement of this goal with an advanced, ultra-high temperature compliant foilgas bearing. Achieving this goal required a combination of high temperature foil material, a unique elastic-tribo-thermal barrier coating (KOROLON 2250) and a self-adapting compliant configuration. The authors describe the experimental hardware designs and design considerations of the two differently sized test rigs used to demonstrate foil bearings operating above 815°C (1500°F). Finally, the authors present and discuss the results of testing at temperatures to 870°C (1600°F).

Evaluation of Alternate High Temperature Coatings to Improve Hot Corrosion Resistance in a Shipboard Environment

2009 ◽  
Author(s):  
David A. Shifler ◽  
Dennis M. Russom ◽  
Bruce E. Rodman
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Corrosion Fatigue ◽  
Hot Corrosion ◽  
Turbine Engines ◽  
Type I ◽  
Gas Turbine Engines ◽  
Type Ii ◽  
Turbine Engine ◽  
Type Ii Hot Corrosion

501-K34 marine gas turbine engines serve as auxiliary power sources for the U.S. Navy’s DDG-51 Class. It is desired that 501-K34 marine gas turbine engines have a mean time between removal of 20K hours. While some engines have approached this goal, others have fallen significantly short. A primary reason for this shortfall is hot corrosion (Type I and Type II) damage in the turbine area (more specifically the first row turbine hardware) due to both intrusion of salts from the marine air and from sulfur in the gas turbine combustion fuel. The Navy’s technical community recognizes that engine corrosion problems are complex in nature and are often tied to the design of the overall system. For this reason, two working groups were formed. One group focuses on the overall ship system design and operation, including the inlet and fuel systems. The second, the corrosion issues working group, will review the design and performance of the turbine itself and develop sound, practical, economical, and executable changes to engine design that will make it more robust and durable in the shipboard operating environment. Metallographic examination of unfailed blades removed from a marine gas turbine engine with 18000 operating hours showed that the coating thickness under the platform and in the curved area of transition between the platform to the blade stem was either very thin, or in a few cases, non-existent on each unfailed blade. Type II hot corrosion was evident at these locations under the platform. It was also observed that this corrosion under the platform led to corrosion fatigue cracking of first stage turbine blades due to poor coating quality (high porosity and variable thickness). Corrosion fatigue cracks initiated at several hot corrosion sites and had advanced through the stems to varying degrees. Cracking in a few blades had advanced to the point that would have led to premature blade failure. Low velocity, atmospheric-pressure burner-rig (LVBR) tests were conducted for 1000 hours to evaluate several alternative high-temperature coatings in both Type I and Type II hot corrosion environments. The objectives of this paper are to: (1) report the results of the hot corrosion performance of alternative high temperature coating systems for under the platform of the 1st stage blade of 501-K34 gas turbine engine, (2) compare the performance of these alternative coating systems to the current baseline 1st stage blade coating, and (3) down select the best performing coating systems (in terms of their LVBR hot corrosion and thermal cycling resistance) to implement on future 501-K34 first stage blades for the Fleet.

Development and Investigation of Ceramic Parts for Gas-Turbine Engines

1997 ◽  
Author(s):  
Youry A. Nozhnitsky ◽  
Youlia A. Fedina ◽  
Anatoly D. Rekin ◽  
Nickolai I. Petrov
Keyword(s):  
Gas Turbine ◽  
Ceramic Materials ◽  
Mechanical Tests ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Metallic Materials ◽  
Turbine Engine ◽  
Protective Medium ◽  
Gas Generators ◽  
Engine Components

For years of time there have been conducted the investigations of gas-turbine engine parts made of carbon-carbon and ceramic materials. This paper presents mainly the results of works done to create engine components of ceramic materials. There are given the investigation results on development of equipment and methods intended for use in determining the characteristics of heat-resistant non-metallic materials under ultra high temperature conditions. The unique tooling is developed to be used for conducting mechanical tests in different conditions (vacuum, protective medium, air) at temperatures up to 2200°C. There are considered three possible fields of application of ceramic materials, that are, turbine (1), combustion chamber and other stator components operating at high temperatures (2), bearings (3). Different ceramic elements are designed and manufactured, their structural strength is investigated in the laboratory faculties and also as part of engine gas generators.

A Probabilistic Framework for Risk Prediction of Gas Turbine Engine Components With Inherent or Induced Material Anomalies

2005 ◽  
Author(s):  
Michael P. Enright ◽  
R. Craig McClung ◽  
Luc Huyse
Keyword(s):  
Risk Assessment ◽  
Gas Turbine ◽  
Gas Turbine Engine ◽  
Turbine Engines ◽  
Manufacturing Processes ◽  
Gas Turbine Engines ◽  
Probabilistic Framework ◽  
Turbine Engine ◽  
Risk Of Fracture ◽  
Engine Components

Rare anomalies may be introduced during the metallurgical or manufacturing processes that may lead to uncontained failures of aircraft gas turbine engines. The risk of fracture associated with these anomalies can be quantified using a probabilistic fracture mechanics approach. In this paper, a general probabilistic framework is presented for risk assessment of gas turbine engine components subjected to either inherent or induced material anomalies. A summary of efficient computational methods that are applicable to this problem is also provided.

Performance Evaluation of High Temperature Coatings for Hot Section Turbine Components

2005 ◽  
Author(s):  
David A. Shifler ◽  
Dennis M. Russom ◽  
Bruce E. Rodman
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Hot Corrosion ◽  
Gas Turbine Engine ◽  
Turbine Engines ◽  
Type I ◽  
Gas Turbine Engines ◽  
Type Ii ◽  
Power Sources ◽  
Turbine Engine

501-K34 marine gas turbine engines serve as auxiliary power sources for the U.S. Navy’s DDG-51 Class ships. It is desired that 501-K34 marine gas turbine engines have a mean time between removal of 20K hours. While some engines have approached this goal, others have fallen significantly short. A primary reason for this shortfall is hot corrosion (Type I and Type II) damage in the hot section turbine area due to both intrusion of salts from the marine air and from sulfur in the gas turbine combustion fuels. Previous metallographic examination of several unfailed blades removed from a marine gas turbine engine after 18000 operating hours showed that the coating thickness under the platform and in the curved area of transition between the platform to the blade stem was either very thin, porous, and in a few cases, non-existent on each unfailed blade. Type II hot corrosion was evident at these locations under the platform. Corrosion fatigue cracks initiated at several hot corrosion sites and had advanced through the blade stems to varying degrees. Cracking in a few blades had advanced to the point that blade failure was imminent. The objectives of this paper are to: (1) report the hot corrosion results of alternative high temperature coating systems on Alloy M247 and Alloy 792 for hot section components of the 501-K34 gas turbine engine using a low velocity, atmospheric-pressure burner-rig (LVBR), (2) compare and rank hot corrosion performance of these coatings systems to the baseline coating/substrate system (2) down select the best performing coating systems (in terms of LVBR hot corrosion and thermal cycling resistance) to implement on future hot section components in the 501-K34 engine for the Fleet.

Turbotest: A Computer Program for Rig Test Analysis of Arbitrary Gas Turbine Engines

1984 ◽  
Author(s):  
J. R. Palmer ◽  
Yong-Gen Gu
Keyword(s):  
Gas Turbine ◽  
Test Data ◽  
Hydrocarbon Fuel ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Test Analysis ◽  
Turbine Engine ◽  
Wide Range ◽  
Design Values ◽  
Engine Components

This paper presents a computer model called ‘TURBOTEST’ which is applicable both to analysis of gas turbine engine rig tests and to simulation of engine steady-state performance. As with the earlier ‘TURBOFLEXI’ model a wide range of gas turbine engines can be simulated, using any kind of hydrocarbon fuel, and allowing for chemical dissociation of the gas, and for the effect of air humidity. In addition, however, for the particular requirements of rig test analysis, the following new features have been developed and incorporate:- (a) It can carry out rig test analysis for a wide range of gas turbine engines if all the necessary test data are presented. (b) If the test data is incomplete, a computer simulation of the engine can be used to complete the analysis. (c) Performance deterioration of engine components can be detected by comparing the results of a test analysis and of a parallel simulation using stored characteristics of engine components in the “as new” condition. The program has been tested on simulated test data generated by engine models such as a turbojet and a turbofan. The results show it has close and repeatable agreement with design values. Further tests of the model have been carried out by applying it to the actual engine rig test data.

scholarly journals Leakage and Power Loss Test Results for Competing Turbine Engine Seals

2004 ◽  
Author(s):  
Margaret P. Proctor ◽  
Irebert R. Delgado
Keyword(s):  
High Temperature ◽  
Power Loss ◽  
High Speed ◽  
Operating Conditions ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Test Results ◽  
Test Rig ◽  
Labyrinth Seals ◽  
Turbine Engine

Advanced brush and finger seal technologies offer reduced leakage rates over conventional labyrinth seals used in gas turbine engines. To address engine manufactures’ concerns about the heat generation and power loss from these contacting seals, brush, finger, and labyrinth seals were tested in the NASA High Speed, High Temperature Turbine Seal Test Rig. Leakage and power loss test results are compared for these competing seals for operating conditions up to 922 K (1200 °F) inlet air temperature, 517 KPa (75 psid) across the seal, and surface velocities up to 366 m/s (1200 ft/s).

The Application of Ceramics to the Small Gas Turbine

1970 ◽  
Author(s):  
A. F. McLean
Keyword(s):  
Gas Turbine ◽  
Lower Cost ◽  
Ceramic Materials ◽  
Turbine Engines ◽  
Inlet Temperature ◽  
Gas Turbine Engines ◽  
Turbine Inlet Temperature ◽  
Turbine Engine ◽  
Engine Components ◽  
Processing Techniques

This paper reviews the limitations today’s superalloys exercise on the realization of the potential of the gas turbine engine. Ceramic materials are suggested as a means of achieving lower cost and higher turbine inlet temperature in small gas turbine engines. The paper serves to introduce ceramic materials and processing techniques and identifies silicon nitride, silicon carbide and lithium-alumina-silicate as promising materials for high temperature turbine engine components.

Power Turbine Vane Ring (PT6 Engine) Repair Development

1986 ◽  
Author(s):  
N. Sourial
Keyword(s):  
Gas Turbine ◽  
High Technology ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Turbine Engine ◽  
New Methods ◽  
Power Turbine ◽  
Turbine Vane ◽  
Engine Components ◽  
Repair Techniques

Today’s high technology gas turbine engines incorporate the world’s most exotic alloys and are built to some of the most precise dimensional tolerances encountered in any industry. The constant drive for increased performance while substantially reducing fuel consumption and weight has pushed engine components and their designers to limits never before realized. To achieve these limits new methods and materials have evolved; not exclusively in the production of the engines but also in the repair and maintenance of them. The typical problems encountered in repair and maintenance are numerous and varied as are their solutions. This paper, however, will concentrate on one in particular and that is the typical damage encountered on a first stage power turbine vane ring and the technology employed to repair such damage. The vane ring was chosen because it is representative of a common problem encountered by all gas turbine engine manufacturers and simultaneously involves some of the most up to date repair techniques to restore it.

Sign in / Sign up

Export Citation Format

Share Document