Influence of a Thermal Barrier Coating on the Performance of a Turboprop Engine

1992 ◽  
Author(s):  
J. D. MacLeod ◽  
J. C. G. Laflamme
Keyword(s):  
Surface Roughness ◽  
Thermal Barrier Coating ◽  
Coating Thickness ◽  
Ceramic Coating ◽  
National Research Council ◽  
Engine Performance ◽  
Thermal Barrier ◽  
Barrier Coating ◽  
Project Objectives ◽  
The Impact

Under the sponsorship of the Canadian Department of National Defence, the Engine Laboratory of the National Research Council of Canada has evaluated the influence of applying a thermal barrier coating on the performance of a gas turbine engine. The effort is aimed at quantifying the performance effects of a particular ceramic coating on the first stage turbine vanes. The long term objective of the program is to both assess the relative change in engine performance and compare against the claimed benefits of higher possible turbine inlet temperatures, longer time in service and increased time between overhauls. The engine used for this evaluation was the Allison T56 turboprop with the first stage turbine nozzles coated with the Chromalloy RT-33 ceramic coating. The issues addressed in testing this particular type of hot section coating were; 1) effect of coating thickness on nozzle effective flow area; 2) surface roughness influence on turbine efficiency; This paper describes the project objectives, the experimental installation, and the results of the performance evaluations. Discussed are performance variations due to coating thickness and surface roughness on engine performance characteristics. As the performance changes were small, a rigorous measurement uncertainty analysis is included. The coating application process, and the affected overhaul procedures are examined. The results of the pre- and post-coating turbine testing are presented, with a discussion of the impact on engine performance.

The impact of piston thermal barrier coating roughness on high-load diesel operation

2019 ◽  
pp. 146808741989348 ◽  
Author(s):  
Eric Gingrich ◽  
Michael Tess ◽  
Vamshi Korivi ◽  
Peter Schihl ◽  
John Saputo ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Surface Roughness ◽  
Thermal Barrier Coating ◽  
Engine Performance ◽  
Operating Conditions ◽  
Thermal Barrier ◽  
Engine Operation ◽  
Barrier Coating ◽  
The Impact ◽  
High Output

Thermal barrier coatings of various thickness and surface roughness were applied to the piston crown of a single-cylinder research engine and tested over a range of high-output diesel operating conditions, some near 30 bar gross indicated mean effective pressure. Three yttria-stabilized zirconia coated pistons were compared to a baseline metal piston. At each operating condition, a start-of-injection sweep was conducted to generate efficiency trends and find the optimal combustion phasing. Three variations of pistons coated with a graded-layer thermal barrier coating were tested: (1) 0.185 mm coating thickness with a surface roughness of approximately Ra = 11.8 µm, (2) 0.325 mm thickness with Ra = 11.8 µm, and (3) 0.325 mm thickness with Ra = 6.0 µm. Both coated pistons with Ra = 11.8 µm did not show any statistically significant improvement to engine performance when compared to the metal baseline piston, but did produce higher filter smoke numbers. The coated piston with Ra = 6.0 µm and 0.325 mm showed an increase of gross indicated thermal efficiency of up to 3.5% (relative) compared to the metal baseline piston for operating conditions comparable to standard engine operation and a reduction of filter smoke number back to the metal baseline. The increase in efficiency was found to correlate with additional late-cycle apparent heat release and a reduction in in-cylinder heat transfer. The very high-output conditions showed statistically insignificant changes in performance or heat transfer, which may have been related to the long injection duration used for these cases targeting outside of the piston bowl.

Surface Roughness Measurement of Thermal Barrier Coating using Terahertz Waves

2017 ◽  
Vol 137 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Tetsuo Fukuchi ◽  
Norikazu Fuse ◽  
Mitsutoshi Okada ◽  
Tomoharu Fujii ◽  
Maya Mizuno ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Thermal Barrier Coating ◽  
Thermal Barrier ◽  
Roughness Measurement ◽  
Terahertz Waves ◽  
Surface Roughness Measurement ◽  
Barrier Coating

scholarly journals Effect of Thermal Barrier Coating on the Performance and Emissions of Diesel Engine Operated with Conventional Diesel and Palm Oil Biodiesel

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 692
Author(s):  
Navin Ramasamy ◽  
Mohammad Abul Kalam ◽  
Mahendra Varman ◽  
Yew Heng Teoh
Keyword(s):  
Thermal Barrier Coating ◽  
Palm Oil ◽  
Silicon Oxide ◽  
Engine Performance ◽  
Spray Coating ◽  
Thermal Barrier ◽  
Performance And Emission ◽  
Barrier Coating ◽  
Carbon Dioxide Co2 ◽  
Palm Oil Biodiesel

In this study, the performance and emission of a thermal barrier coating (TBC) engine which applied palm oil biodiesel and diesel as a fuel were evaluated. TBC was prepared by using a series of mixture consisting different blend ratio of yttria stabilized zirconia (Y2O3·ZrO2) and aluminum oxide-silicon oxide (Al2O3·SiO2) via plasma spray coating technique. The experimental results showed that mixture of TBC with 60% Y2O3·ZrO2 + 40% Al2O3·SiO2 had an excellent nitrogen oxide (NO), carbon monoxide (CO), carbon dioxide (CO2), and unburned hydrocarbon (HC) reductions compared to other blend-coated pistons. The finding also indicated that coating mixture 50% Y2O3·ZrO2 + 50% Al2O3·SiO2 had the highest brake thermal efficiency (BTE) and lowest of brake specific fuel consumption (BSFC) compared to all mixture coating. Reductions of HC and CO emissions were also recorded for 60% Y2O3·ZrO2 + 40% Al2O3·SiO2 and 50% Y2O3·ZrO2 + 50% Al2O3·SiO2 coatings. These encouraging findings had further proven the significance of TBC in enhancing the engine performance and emission reductions operated with different types of fuel.

Comparison of Cooling Film Development Calculations for Transpiration Cooled Flat Plates With Different Turbulence Models

2001 ◽  
Author(s):  
Dieter E. Bohn ◽  
Norbert Moritz
Keyword(s):  
Fluid Flow ◽  
Thermal Barrier Coating ◽  
Solid Body ◽  
Turbulence Models ◽  
Thermal Barrier ◽  
Flat Plates ◽  
Jet Mixing ◽  
Barrier Coating ◽  
Film Development ◽  
The Impact

A transpiration cooled flat plate configuration is investigated numerically by application of a 3-D conjugate fluid flow and heat transfer solver, CHT-Flow. The geometrical setup and the fluid flow conditions are derived from modern gas turbine combustion chambers. The plate is composed of three layers, a substrate layer (CMSX-4) with a thickness of 2 mm, a bondcoat (MCrAlY) with thickness 0,15 mm, and a thermal barrier coating (EB-PVD, Yttrium stabilized ZrO2) with thickness 0,25 mm, respectively. The numerical grid contains the coolant supply (plenum), the solid body, and the main flow area upon the plate. The transpiration cooling is realized by finest drilled holes with a diameter of 0,2 mm that are shaped in the region of the thermal barrier coating. The holes are inclined with an angle of 30°. Two different configurations are investigated that differ in the shaping of the holes in their outlet region. The numerical investigation focus on the influence of different turbulence models on the results. Regarding the secondary flow, the cooling film development and complex jet mixing vortex systems are analyzed. Additionally, the impact on the temperature distribution both on the plate surface and in the plate is investigated. It is shown that the choice of the turbulence model has a significant influence on the prediction of the flow structure, and, consequently, on the calculation of the thermal load of the solid body.

A Study of the Effects of Thermal Barrier Coating Surface Roughness on the Boundary Layer Characteristics of Gas Turbine Aerofoils

1988 ◽  
Vol 110 (1) ◽  
pp. 88-93 ◽  
Author(s):  
R. M. Watt ◽  
J. L. Allen ◽  
N. C. Baines ◽  
J. P. Simons ◽  
M. George
Keyword(s):  
Surface Roughness ◽  
Reynolds Number ◽  
Gas Turbine ◽  
Thermal Barrier Coating ◽  
Guide Vane ◽  
Thermal Barrier ◽  
Coating Surface ◽  
Barrier Coating ◽  
Nozzle Guide Vane ◽  
Nozzle Guide

The effect of thermal barrier coating surface roughness on the aerodynamic performance of gas turbine aerofoils has been investigated for the case of a profile typical of current first-stage nozzle guide vane design. Cascade tests indicate a potential for significant extra loss, depending on Reynolds number, due to thermal barrier coating in its “as-sprayed” state. In this situation polishing coated vanes is shown to be largely effective in restoring their performance. The measurements also suggest a critical low Reynolds number below which the range of roughness tested has no effect on cascade efficiency. Transition detection involved a novel use of thin-film anemometers painted and fired onto the TBC surfaces.

Thermographic measurement of thermal barrier coating thickness

2005 ◽  
Author(s):  
Steven M. Shepard ◽  
Yu L. Hou ◽  
James R. Lhota ◽  
David Wang ◽  
Tasdiq Ahmed
Keyword(s):  
Thermal Barrier Coating ◽  
Coating Thickness ◽  
Thermal Barrier ◽  
Barrier Coating ◽  
Thermographic Measurement

Delamination Cracking in Thermal Barrier Coating System

2002 ◽  
Vol 124 (4) ◽  
pp. 922-930 ◽  
Author(s):  
Y. C. Zhou ◽  
T. Hashida
Keyword(s):  
Thermal Stress ◽  
Temperature Gradient ◽  
Thermal Barrier Coating ◽  
Ceramic Coating ◽  
Compressive Load ◽  
Bending Moment ◽  
Thermal Barrier ◽  
Barrier Coating ◽  
Thermal Growth ◽  
Coating Delamination

Delamination cracking in thermal barrier coating (TBC) system is studied with the newly developed theoretical model. A semi-infinite long interface crack is pre-existing. The thermal stress and temperature gradient in TBC system are designated by a membrane stress P and a bending moment M. In this case, the effects of plastic deformation, creep of ceramic coating, as well as thermal growth oxidation and temperature gradient in TBC system are considered in the model due to the fact that these effects are considered in the calculation of thermal stress. The energy release rate, mode I and mode II stress intensity factors, as well as mode mixed measure ψ, are derived. The emphatic discussion about PSZ/Ni-alloy reveals that the TBC system may not fail in the form of coating delamination during the period of heat hold. However, the failure may be in the form of coating delamination during cooling or in the heating period during the second cycle or later cycles. The conclusion is consistent with the experimental observations. The delamination of ceramic coating is induced by the compressive load in the coating.

Compressor Coating Effects on Gas Turbine Engine Performance

1991 ◽  
Vol 113 (4) ◽  
pp. 530-534 ◽  
Author(s):  
J. D. MacLeod ◽  
J. C. G. Laflamme
Keyword(s):  
National Research Council ◽  
Engine Performance ◽  
Application Process ◽  
Turbine Engine ◽  
Coating Application ◽  
Turboprop Engine ◽  
Compressor Performance ◽  
Department Of National Defence ◽  
Project Objectives ◽  
The Impact

In an attempt to increase the time between maintenance actions and to improve performance retention of turboprop engines installed in transport and maritime patrol aircraft, the Canadian Department of National Defence is evaluating an erosion and corrosion-resistant blade coating, for use on compressors. As coatings could appreciably alter engine performance by virtue of their application thickness and surface quality, the National Research Council of Canada was asked to quantify any performance changes that could occur. A project was initiated, utilizing a new Allison T56 turboprop engine, to assess not only the performance changes resulting from the coating, but also those from dismantling and reassembling the compressor, since the compressor must be completely disassembled to apply the coating. This paper describes the project objectives, the experimental installation, and the measured effects of the coating application on compressor performance. Performance variations due to compressor rebuilds on both engine and compressor characteristics are discussed. As the performance changes were small, a rigorous measurement uncertainty analysis is included. The coating application process and the affected overhaul procedures are examined. The results of the pre- and postcoating compressor testing are presented, with a discussion of the impact on engine performance.

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