Effects of the Intake Air Humidity on the Gas Turbine Performance Monitoring

Gas turbine engines (GTEs) are extensively used in locations with high humidity such as offshore platforms. However, in the dry regions, GTEs are often equipped with water spray inlet coolers for warm seasons. In both cases, the moisture affects the thermodynamic properties of the intake air and drifts the performance off the dry condition, especially during the warm days, when the moisture content of the air is high and the inlet air cooler is operational. In this paper, a detailed steady state model is proposed to simulate the GTE performance with the humid air, and it is linked with a thermodynamic model to quantify the total moisture content of the air after the cooler. The developed framework is used to analyze the operating data of a GTE during the three years of service. The results are then utilized for model-based performance monitoring of the GTE, using a recently introduced performance indicator. A comparative analysis is performed between the results received from the primary model overlooking the humidity effects, and the developed enhanced performance model with humidity effects. A better accuracy for the performance indicator was observed where the enhanced model is employed, suggesting the importance of considering the intake air humidity for model-based performance monitoring.

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Hybrid Modeling of Heavy Duty Gas Turbines for On-Line Performance Monitoring

Volume 6: Ceramics; Controls, Diagnostics and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2014-26015 ◽

2014 ◽

Cited By ~ 1

Author(s):

Thomas Palmé ◽

Francois Liard ◽

Dan Cameron

Keyword(s):

Gas Turbine ◽

Surrogate Model ◽

Gas Turbines ◽

Performance Monitoring ◽

Performance Model ◽

Heavy Duty ◽

Operational Parameters ◽

Actual Performance ◽

Real Gas ◽

The Real

Due to their complex physics, accurate modeling of modern heavy duty gas turbines can be both challenging and time consuming. For online performance monitoring, the purpose of modeling is to predict operational parameters to assess the current performance and identify any possible deviation between the model’s expected performance parameters and the actual performance. In this paper, a method is presented to tune a physical model to a specific gas turbine by applying a data-driven approach to correct for the differences between the real gas turbine operation and the performance model prediction of the same. The first step in this process is to generate a surrogate model of the 1st principle performance model through the use of a neural network. A second “correction model” is then developed from selected operational data to correct the differences between the surrogate model and the real gas turbine. This corrects for the inaccuracies between the performance model and the real operation. The methodology is described and the results from its application to a heavy duty gas turbine are presented in this paper.

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Computer Models for Education on Performance Monitoring and Diagnostics of Gas Turbines

International Journal of Mechanical Engineering Education ◽

10.7227/ijmee.30.3.2 ◽

2002 ◽

Vol 30 (3) ◽

pp. 204-218 ◽

Cited By ~ 2

Author(s):

K. Mathioudakis ◽

A. Stamatis ◽

A. Tsalavoutas ◽

N. Aretakis

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Performance Monitoring ◽

Measurement Data ◽

Performance Model ◽

Operating Conditions ◽

Engine Operation ◽

Monitoring And Diagnostics ◽

Engine Components ◽

The Way

The paper discusses how performance models can be incorporated in education on the subject of gas turbine performance monitoring and diagnostics. A particular performance model, built for educational purposes, is employed to demonstrate the different aspects of this process. The way of building a model is discussed, in order to ensure the connection between the physical principles used for diagnostics and the structure of the software. The first aspect discussed is model usage for understanding gas turbine behaviour under different operating conditions. Understanding this behaviour is essential, in order to have the possibility to distinguish between operation in ‘healthy’ and ‘faulty’ engine condition. A graphics interface is used to present information in different ways such as operating line, operating points on component maps, interrelation between performance variables and parameters. The way of studying faulty engine operation is then presented, featuring a novel comparison to existing simulation programs. Faults can be implanted into different engine components and their impact on engine performance studied. The notion of fault signatures on measured quantities is explained. The model has also a diagnostic capability, allowing the introduction of measurement data from faulty engines and providing a diagnosis, namely a picture of how the performance of engine components has deviated from a ‘healthy’ condition

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A Development of EMAS (Easy Maintenance Assistance Solution) for Industrial Gas Turbine Engine

Volume 6: Ceramics; Controls, Diagnostics and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2014-26945 ◽

2014 ◽

Author(s):

Myungkuk Lee ◽

Myoung-Cheol Kang ◽

Hongsuk Roh ◽

Jayoung Ki

Keyword(s):

Power Plant ◽

Gas Turbine ◽

Combined Cycle ◽

Performance Model ◽

Maintenance Cost ◽

Analysis Model ◽

Optimal Point ◽

Combined Cycle Power Plant ◽

Model Based ◽

Turbine Performance

The solution was developed for the maintenance decision support of combined cycle power plant gas turbine. The developed solution provides the calculated result of optimal overhaul interval through the following modules: Overhaul Interval Prediction, Real Time Performance Monitoring, Model-Based Diagnostics, Performance Trend Analysis, Compressor Washing Period Management, and Blade Path Temperature Analysis. Model-Based Diagnostics module analyzed the differences between the data of MHI501G gas turbine performance model and the online measurement. Gas turbine performance model can be modified by the type of gas turbine of each combined cycle power plant. Compressor washing management module suggests the optimal point of balancing between the compressor performance and the maintenance cost. The predicted results of compressor washing period and overhaul period are able to support the operators in combined cycle power plant to make a proper decision of maintenance task. The developed solution was applied to MHI501G gas turbine and is, in present, on the process of field test at GUNSAN combined cycle power plant, South Korea.

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Instructing the Principles of Gas Turbine Performance Monitoring and Diagnostics by Means of Interactive Computer Models

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education ◽

10.1115/2000-gt-0584 ◽

2000 ◽

Cited By ~ 1

Author(s):

K. Mathioudakis ◽

A. Stamatis ◽

A. Tsalavoutas ◽

N. Aretakis

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Performance Monitoring ◽

Measurement Data ◽

Engine Performance ◽

Performance Model ◽

Operating Conditions ◽

Engine Operation ◽

Turbine Performance ◽

Engine Components

The paper discusses how the principles employed for monitoring the performance of gas turbines in industrial duty can be explained by using suitable Gas Turbine performance models. A particular performance model that can be used for educational purposes is presented. The model allows the presentation of basic rules of gas turbine engine behavior and helps understanding different aspects of its operation. It is equipped with a graphics interface, so it can present engine operating point data in a number of different ways: operating line, operating points of the components, variation of particular quantities with operating conditions etc. Its novel feature, compared to existing simulation programs, is that it can be used for studying cases of faulty engine operation. Faults can be implanted into different engine components and their impact on engine performance studied. The notion of fault signatures on measured quantities is clearly demonstrated. On the other hand, the model has a diagnostic capability, allowing the introduction of measurement data from faulty engines and providing a diagnosis, namely a picture of how the performance of engine components has deviated from nominal condition, and how this information gives the possibility for fault identification.

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Fault Diagnostics Using Genetic Algorithm for Advanced Cycle Gas Turbine

Volume 2: Turbo Expo 2002, Parts A and B ◽

10.1115/gt2002-30021 ◽

2002 ◽

Cited By ~ 11

Author(s):

Suresh Sampath ◽

Ankush Gulati ◽

Riti Singh

Keyword(s):

Objective Function ◽

Gas Turbine ◽

Model Simulation ◽

Engine Performance ◽

Simulated Data ◽

Performance Model ◽

Simple Cycle ◽

Fault Diagnostics ◽

Model Based ◽

The Difference

This paper describes a new approach to the development of a fault diagnostics and prognostic capability for an advanced cycle gas turbine. It is based on techniques using sensor based and model based information. Sensor based information is the actual information obtained from the real engine and the model based information comes from the data obtained from engine performance model simulation with a permutation of implanted faults taking into account sensor noise and bias. The approach adopted here is to minimize an objective function which represents the difference between the actual and simulated data and the minimized objective function allows us identify the nature of fault. After the initial success with simple cycle engines, it was decided to extend this technique to advanced cycle engines. The technique is being tested on an in-house model of an intercooled recuperated engine with variable geometry similar to the ICR-WR21cycle. A detailed analysis of the technique applied to simple cycle and advanced cycle will be presented.

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Model Based Control of Moisture Sorption in a Historical Interior

Acta Polytechnica ◽

10.14311/726 ◽

2005 ◽

Vol 45 (4) ◽

Author(s):

P. Zítek ◽

T. Vyhlídal

Keyword(s):

Moisture Content ◽

Moisture Sorption ◽

Point Of View ◽

Historical Buildings ◽

Air Humidity ◽

Preventive Conservation ◽

Model Based Control ◽

Yearly Cycle ◽

Model Based ◽

The Impact

This paper deals with a novel scheme for microclimate control in historical exhibition rooms, inhibiting moisture sorption phenomena that are inadmissible from the preventive conservation point of view. The impact of air humidity is the most significant harmful exposure for a great deal of the cultural heritage deposited in remote historical buildings. Leaving the interior temperature to run almost its spontaneous yearly cycle, the proposed non-linear model-based control protects exhibits from harmful variations in moisture content by compensating the temperature drifts with an adequate adjustment of the air humidity. Already implemented in a medieval interior since 1999, the proposed microclimate control has proved capable of permanently maintaining constant a desirable moisture content in organic or porous materials in the interior of a building.

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