Estimation of Thermal Barrier Coating Surface Temperature and Heat Flux Profiles in a Low Temperature Combustion Engine Using a Modified Sequential Function Specification Approach

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Ryan N. O'Donnell ◽  
Thomas R. Powell ◽  
Zoran S. Filipi ◽  
Mark A. Hoffman
Keyword(s):  
Heat Flux ◽  
Surface Temperature ◽  
Thermal Barrier Coating ◽  
Combustion Engine ◽  
Ex Situ ◽  
Multiple Time Scales ◽  
Thermal Barrier ◽  
Coating Surface ◽  
Barrier Coating ◽  
Sequential Function Specification

A modified form of the sequential function specification method (SFSM) is developed with specific consideration given to multiple time scales in an effort to avoid overregularization of the solution estimates. The authors extend their approach to solve the inverse heat conduction problem (IHCP) associated with the application of thermal barrier coatings (TBC) to in-cylinder surfaces of an internal combustion engine. Subsurface temperature measurements are used to calculate surface heat flux profiles. The modified inverse solver is validated ex situ using a custom fabricated radiation chamber. The solution methodology is extended in situ to evaluate temperature data collected from a single-cylinder research engine operating in homogeneous charge compression ignition (HCCI) mode. Crank angle resolved, thermal barrier coating surface temperature and heat flux profiles are produced—enabling correlation of thermal conditions at the gas-wall boundary with engine performance, emission, and efficiency metrics.

The Effect of Thermal Barrier Coating Surface Temperature on the Adhesion Behavior of CMAS Deposits

2021 ◽  
Author(s):  
Robert Clark ◽  
Nicholas Plewacki ◽  
Pritheesh Gnanaselvam ◽  
Jeffrey Bons ◽  
Vaishak Viswanathan
Keyword(s):  
Surface Temperature ◽  
Thermal Barrier Coating ◽  
Thermal Barrier ◽  
Coating Surface ◽  
Barrier Coating ◽  
Adhesion Behavior

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.

Determination of Thermal Barrier Coatings Average Surface Temperature After Engine Operation for Lifetime Validation

2012 ◽  
Vol 134 (12) ◽  
Author(s):  
Grégoire Witz ◽  
Hans-Peter Bossmann
Keyword(s):  
Surface Temperature ◽  
Thermal Barrier Coating ◽  
Thermal Barrier Coatings ◽  
Operating Conditions ◽  
Thermal Barrier ◽  
Engine Operation ◽  
Barrier Coatings ◽  
Average Surface ◽  
Barrier Coating

Assessment of ex-service parts is important for the power generation industry. It gives us the opportunity to correlate part conditions to specific operating conditions like fuel used, local atmospheric conditions, operating regime, and temperature load. For assessment of thermal barrier coatings, one of the most valuable pieces of information is the local thermal condition. A method has been developed in Alstom, allowing determination of a thermal barrier coating average surface temperature after engine operation. It is based on the analysis of the phase composition of the thermal barrier coating by the acquisition of an X-ray diffraction spectrum of the coating surface, and its analysis using Rietveld refinement. The method has been validated by comparing its outcome to thermal models and base metal temperature mapping data. It is used for assessment of combustor and turbine coatings with various purposes: Determination of remnant coating life, building of lifing models, or determination of the coating degradation mechanisms under some specific operating conditions. Examples will be presented showing applications of this method.

scholarly journals CFD/FEA Co-Simulation Framework for Analysis of the Thermal Barrier Coating Design and Its Impact on the HD Diesel Engine Performance

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2044
Author(s):  
Sean Moser ◽  
K. Dean Edwards ◽  
Tobias Schoeffler ◽  
Zoran Filipi
Keyword(s):  
Heat Flux ◽  
Boundary Conditions ◽  
Thermal Barrier Coating ◽  
Thermal Barrier Coatings ◽  
Thermal Barrier ◽  
Barrier Coatings ◽  
Barrier Coating ◽  
Fea Modeling ◽  
Coating Design ◽  
Insight Into

Thermal barrier coatings (TBCs) have been investigated both experimentally and through simulation for mixing controlled combustion (MCC) concepts as a method for reducing heat transfer losses and increasing cycle efficiency, but it is still a very active research area. Early studies were inconclusive, with different groups discovering obstacles to realizing the theoretical potential. Nuanced papers have shown that coating material properties, thickness, microstructure, and surface morphology/roughness all can impact the efficacy of the thermal barrier coating and must be accounted for. Adding to the complexities, a strong spatial and temporal heat flux inhomogeneity exists for mixing controlled combustion (diesel) imposed onto the surfaces from the impinging flame jets. In support of the United States Department of Energy SuperTruck II program goal to achieve 55% brake thermal efficiency on a heavy-duty diesel engines, this study sought to develop a deeper insight into the inhomogeneous heat flux from mixing controlled combustion on thermal barrier coatings and to infer concrete guidance for designing coatings. To that end, a co-simulation approach was developed that couples high-fidelity computational fluid dynamics (CFD) modeling of in-cylinder processes and combustion, and finite element analysis (FEA) modeling of the thermal barrier-coated and metal engine components to resolve spatial and temporal thermal boundary conditions. The models interface at the surface of the combustion chamber; FEA modeling predicts the spatially resolved surface temperature profile, while CFD develops insights into the effect of the thermal barrier coating on the combustion process and the boundary conditions on the gas side. The paper demonstrates the capability of the framework to estimate cycle impacts of the temperature swing at the surface, as well as identify critical locations on the piston/thermal barrier coating that exhibit the highest charge temperature and highest heat fluxes. In addition, the FEA results include predictions of thermal stresses, thus enabling insight into factors affecting coating durability. An example of the capability of the framework is provided to illustrate its use for investigating novel coatings and provide deeper insights to guide future coating design.

scholarly journals The Importance of Thermal Barrier Coating in Compression and Spark Ignition Engines

2020 ◽  
Vol 9 (4) ◽  
pp. 1738-1742
Keyword(s):  
Thermal Barrier Coating ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Renewable Energy Sources ◽  
Internal Combustion ◽  
Spark Ignition ◽  
Thermal Barrier ◽  
Combustion Engines ◽  
Spark Ignition Engines ◽  
Barrier Coating

This paper explains the importance of applying thermal barrier coating (TBC) technique in internal combustion engines by providing an effective way of reducing gas emission which are carbon monoxide (CO), oxide of nitrogen (NOX), hydrocarbon (HC) including particulate matter (PM) thereby increasing engine performance (brake thermal efficiency) achieved by applying coating layers on some internal combustion engine parts using materials with low thermal conductivities and matched coefficients of thermal expansion (CTE close to the substrate material) which are mainly ceramics. Energy demand for various activities of life is increasing on a daily basis. The world depends majorly on non-renewable energy sources from fossil fuels to meet these energy demands. To be comfortable in life, better means of transportation and provision of power are required. Compression and spark ignition engines which are also called Internal Combustion Engines (ICEs) provide better transport facilities and power. However, combusting these fuels in automobile and stationary engines produces unfriendly atmosphere, contaminates water and air that are consumed by man. Pollution created as a result of combustion of gases in ICE is one of the worst man made contribution to atmospheric pollution.

THE EFFECT OF THERMAL BARRIER COATING SURFACE TEMPERATURE ON THE ADHESION BEHAVIOR OF CMAS DEPOSITS

2021 ◽  
pp. 1-14
Author(s):  
Robert A. Clark ◽  
Nicholas Plewacki ◽  
Pritheesh Gnanaselvam ◽  
Jeffrey P. Bons ◽  
Vaishak Viswanathan
Keyword(s):  
High Pressure ◽  
Surface Temperature ◽  
Thermal Barrier Coating ◽  
Thermal Barrier ◽  
Back Side ◽  
Gas Temperature ◽  
Front Side ◽  
Barrier Coating ◽  
Inlet Conditions ◽  
Side Flow

Abstract The interaction of thermal barrier coating’s (TBC) surface temperature with CMAS (calcium magnesium aluminosilicate) like deposits in gas turbine hot flowpath hardware is investigated. Small Hastelloy X coupons were coated in TBC and then subjected to a thermal gradient via back-side impingement cooling and front-side impingement heating using the High Temperature Deposition Facility (HTDF) at The Ohio State University (OSU). TBC front-side surface temperatures were varied by changing a constant temperature back-side mass flow, while maintaining a constant hot-side gas temperature and jet velocity representative of modern commercial turbofan high-pressure turbine (HPT) inlet conditions (approximately 1600K and 200 m/s, or Mach 0.25). In this study, Arizona Road Dust (ARD) was utilized to mimic the behavior of CMAS attack on TBCs. Accelerated deposition tests were performed where approximately 1 gram of ARD was injected into the hot side flow while the TBC surface temperature was held at various points above the minimum observed deposition temperature. Surface deposition on the TBC coupons was evaluated using an infrared camera and a backside thermocouple. In addition, an Eulerian-Lagrangian solver was used to model the hot-side impinging jet AND deposition was predicted using the OSU Deposition model. These results can be used to improve physics-based deposition models by providing valuable data relative to CMAS deposition characteristics on TBC surfaces, which modern commercial turbofan high pressure turbines use almost exclusively.

Determination of Cooling Parameters for a High-Speed, True-Scale, Metallic Turbine Vane

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Marc D. Polanka ◽  
James L. Rutledge ◽  
David G. Bogard ◽  
Richard J. Anthony
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Low Temperature ◽  
Surface Temperature ◽  
Thermal Barrier Coating ◽  
Biot Number ◽  
Operating Conditions ◽  
Thermal Barrier ◽  
Barrier Coating ◽  
Overall Effectiveness

Facilities such as the Turbine Research Facility (TRF) at the Air Force Research Laboratory have been acquiring uncooled heat transfer measurements on full-scale metallic airfoils for several years. The addition of cooling flow to this type of facility has provided new capabilities and new challenges. Two primary challenges for cooled rotating hardware are that the true local film temperature is unknown, and cooled thin-walled metallic airfoils prohibit semi-infinite heat conduction calculation. Extracting true local adiabatic effectiveness and the heat transfer coefficient from measurements of surface temperature and surface heat transfer is therefore difficult. In contrast, another cooling parameter, the overall effectiveness (ϕ), is readily obtained from the measurements of surface temperature, internal coolant temperature, and mainstream temperature. The overall effectiveness is a normalized measure of surface temperatures expected for actual operating conditions and is thus an important parameter that drives the life expectancy of a turbine component. Another issue is that scaling ϕ from experimental conditions to engine conditions is dependent on the heat transfer through the part. It has been well-established that the Biot number must be matched for the experimentally measured ϕ to match ϕ at engine conditions. However, the thermal conductivity of both the metal blade and the thermal barrier coating changes substantially from low-temperature to high-temperature engine conditions and usually not in the same proportion. This paper describes a novel method of replicating the correct thermal behavior of the thermal barrier coating (TBC) relative to the metal turbine while obtaining surface temperature measurements and heat fluxes. Furthermore, this paper describes how the ϕ value obtained at the low-temperature conditions can be adjusted to predict ϕ at high-temperature engine conditions when it is impossible to match the Biot number perfectly.

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