PowerGen Gas Turbine Losses and Condition Monitoring: A Loss Data Based Study

Author(s):  
Bin Zhou

In-situ condition monitoring (CM) is a crucial element in protection and predictive maintenance of large rotating Power-Gen equipment such as gas turbines or steam turbines. In this work, selected gas turbine loss events occurring during a recent ten-year period at FM Global clients’ power generation plants were evaluated. For each loss event, a loss scenario or a chain of failures was outlined after investigating the available loss record. These loss events were then categorized based on the nature of the associated loss scenario. The study subsequently focused on the variables that could be monitored in real time to detect the abnormal turbine operating conditions, such as vibration characteristics, temperature, pressure, quality of working fluids and material degradations. These groups of condition monitoring variables were then matched with detectable failures in each loss event and prioritized based on their effectiveness for failure detection and prevention. The detectable loss events and the associated loss value were used in this evaluation process. The study finally concluded with a summary of findings and path-forward actions.

Author(s):  
Bin Zhou

In situ condition monitoring (CM) is a crucial element in protection and predictive maintenance of large rotating PowerGen equipment, such as gas turbines or steam turbines. In this work, selected gas turbine loss events occurring during a recent 10-year period at our clients’ power generation plants were evaluated. For each loss event, a loss scenario or a chain of failures was outlined after investigating the available loss record. These loss events were then categorized based on the nature of the associated loss scenario. The study subsequently focused on the variables that could be monitored in real-time to detect the abnormal turbine operating conditions, such as vibration characteristics, temperature, pressure, quality of working fluids, and material degradations. These groups of CM variables were then matched with detectable failures in each loss event and prioritized based on their effectiveness for failure detection and prevention. The detectable loss events and the associated loss values were used in this evaluation process. The study finally concluded with a summary of findings and path-forward actions.


Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 389
Author(s):  
Jinfu Liu ◽  
Zhenhua Long ◽  
Mingliang Bai ◽  
Linhai Zhu ◽  
Daren Yu

As one of the core components of gas turbines, the combustion system operates in a high-temperature and high-pressure adverse environment, which makes it extremely prone to faults and catastrophic accidents. Therefore, it is necessary to monitor the combustion system to detect in a timely way whether its performance has deteriorated, to improve the safety and economy of gas turbine operation. However, the combustor outlet temperature is so high that conventional sensors cannot work in such a harsh environment for a long time. In practical application, temperature thermocouples distributed at the turbine outlet are used to monitor the exhaust gas temperature (EGT) to indirectly monitor the performance of the combustion system, but, the EGT is not only affected by faults but also influenced by many interference factors, such as ambient conditions, operating conditions, rotation and mixing of uneven hot gas, performance degradation of compressor, etc., which will reduce the sensitivity and reliability of fault detection. For this reason, many scholars have devoted themselves to the research of combustion system fault detection and proposed many excellent methods. However, few studies have compared these methods. This paper will introduce the main methods of combustion system fault detection and select current mainstream methods for analysis. And a circumferential temperature distribution model of gas turbine is established to simulate the EGT profile when a fault is coupled with interference factors, then use the simulation data to compare the detection results of selected methods. Besides, the comparison results are verified by the actual operation data of a gas turbine. Finally, through comparative research and mechanism analysis, the study points out a more suitable method for gas turbine combustion system fault detection and proposes possible development directions.


Author(s):  
Vaidyanathan Krishnan ◽  
J. S. Kapat ◽  
Y. H. Sohn ◽  
V. H. Desai

In recent times, the use of coal gas in gas turbines has gained a lot of interest, as coal is quite abundant as a primary source of energy. However, use of coal gas produces a few detrimental effects that need closer attention. This paper concentrates on one such effect, namely hot corrosion, where trace amounts of sulfur can cause corrosion (or sulfidation) of hot and exposed surfaces, thereby reducing the life of the material. In low temperature hot corrosion, which is the focus of this paper, transport of SO2 from the hot gas stream is the primary process that leads to a chain of events, ultimately causing hot corrosion. The corrosion rate depends on SO2 mass flux to the wall as well as wall surface temperature, both of which are affected in the presence of any film cooling. An analytical model is developed to describe the associated transport phenomena of both heat and mass in the presence of film cooling The model predicts how corrosion rates may be affected under operating conditions. It is found that although use of film cooling typically leads to lower corrosion rate, there are combinations of operating parameters under which corrosion rate can actually increase in the presence of film cooling.


Author(s):  
George M. Koutsothanasis ◽  
Anestis I. Kalfas ◽  
Georgios Doulgeris

This paper presents the benefits of the more electric vessels powered by hybrid engines and investigates the suitability of a particular prime-mover for a specific ship type using a simulation environment which can approach the actual operating conditions. The performance of a mega yacht (70m), powered by two 4.5MW recuperated gas turbines is examined in different voyage scenarios. The analysis is accomplished for a variety of weather and hull fouling conditions using a marine gas turbine performance software which is constituted by six modules based on analytical methods. In the present study, the marine simulation model is used to predict the fuel consumption and emission levels for various conditions of sea state, ambient and sea temperatures and hull fouling profiles. In addition, using the aforementioned parameters, the variation of engine and propeller efficiency can be estimated. Finally, the software is coupled to a creep life prediction tool, able to calculate the consumption of creep life of the high pressure turbine blading for the predefined missions. The results of the performance analysis show that a mega yacht powered by gas turbines can have comparable fuel consumption with the same vessel powered by high speed Diesel engines in the range of 10MW. In such Integrated Full Electric Propulsion (IFEP) environment the gas turbine provides a comprehensive candidate as a prime mover, mainly due to its compactness being highly valued in such application and its eco-friendly operation. The simulation of different voyage cases shows that cleaning the hull of the vessel, the fuel consumption reduces up to 16%. The benefit of the clean hull becomes even greater when adverse weather condition is considered. Additionally, the specific mega yacht when powered by two 4.2MW Diesel engines has a cruising speed of 15 knots with an average fuel consumption of 10.5 [tonne/day]. The same ship powered by two 4.5MW gas turbines has a cruising speed of 22 knots which means that a journey can be completed 31.8% faster, which reduces impressively the total steaming time. However the gas turbine powered yacht consumes 9 [tonne/day] more fuel. Considering the above, Gas Turbine looks to be the only solution which fulfills the next generation sophisticated high powered ship engine requirements.


1974 ◽  
Author(s):  
Marv Weiss

A unique method for silencing heavy-duty gas turbines is described. The Switchback exhaust silencer which utilizes no conventional parallel baffles has at operating conditions measured attenuation values from 20 dB at 63 Hz to 45 dB at higher frequencies. Acoustic testing and analyses at both ambient and operating conditions are discussed.


Author(s):  
Hiroaki Endo ◽  
Robert Wetherbee ◽  
Nikhil Kaushal

An ever more rapidly accelerating trend toward pursuing more efficient gas turbines pushes the engines to hotter and more arduous operating conditions. This trend drives the need for new materials, coatings and associated modeling and testing techniques required to evaluate new component design in high temperature environments and complex stress conditions. This paper will present the recent advances in spin testing techniques that are capable of creating complex stress and thermal conditions, which more closely represent “engine like” conditions. The data from the tests will also become essential references that support the effort in Integrated Computational Materials Engineering (ICME) and in the advances in rotor design and lifing analysis models. Future innovation in aerospace products is critically depended on simultaneous engineering of material properties, product design, and manufacturing processes. ICME is an emerging discipline with an approach to design products, the materials that comprise them, and their associated materials processing methods by linking materials models at multiple scales (Structural, Macro, Meso, Micro, Nano, etc). The focus of the ICME is on the materials; understanding how processes produce material structures, how those structures give rise to material properties, and how to select and/or engineer materials for a given application [34]. The use of advanced high temperature spin testing technologies, including thermal gradient and thermo-mechanical cycling capabilities, combined with the innovative use of modern sensors and instrumentation methods, enables the examination of gas turbine discs and blades under the thermal and the mechanical loads that are more relevant to the conditions of the problematic damages occurring in modern gas turbine engines.


Author(s):  
O. R. Schmoch ◽  
B. Deblon

The peripheral speeds of the rotors of large heavy-duty gas turbines have reached levels which place extremely high demands on material strength properties. The particular requirements of gas turbine rotors, as a result of the cycle, operating conditions and the ensuing overall concepts, have led different gas turbine manufacturers to produce special structural designs to resolve these problems. In this connection, a report is given here on a gas turbine rotor consisting of separate discs which are held together by a center bolt and mutually centered by radial serrations in a manner permitting expansion and contraction in response to temperature changges. In particular, the experience gained in the manufacture, operation and servicing are discussed.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Vedant Dwivedi ◽  
Srikanth Hari ◽  
S. M. Kumaran ◽  
B. V. S. S. S. Prasad ◽  
Vasudevan Raghavan

Abstract Experimental and numerical study of flame and emission characteristics in a tubular micro gas turbine combustor is reported. Micro gas turbines are used for distributed power (DP) generation using alternative fuels in rural areas. The combustion and emission characteristics from the combustor have to be studied for proper design using different fuel types. In this study methane, representing fossil natural gas, and biogas, a renewable fuel that is a mixture of methane and carbon-dioxide, are used. Primary air flow (with swirl component) and secondary aeration have been varied. Experiments have been conducted to measure the exit temperatures. Turbulent reactive flow model is used to simulate the methane and biogas flames. Numerical results are validated against the experimental data. Parametric studies to reveal the effects of primary flow, secondary flow and swirl have been conducted and results are systematically presented. An analysis of nitric-oxides emission for different fuels and operating conditions has been presented subsequently.


Author(s):  
R. Friso ◽  
N. Casari ◽  
M. Pinelli ◽  
A. Suman ◽  
F. Montomoli

Abstract Gas turbines (GT) are often forced to operate in harsh environmental conditions. Therefore, the presence of particles in their flow-path is expected. With this regard, deposition is a problem that severely affects gas turbine operation. Components’ lifetime and performance can dramatically vary as a consequence of this phenomenon. Unfortunately, the operating conditions of the machine can vary in a wide range, and they cannot be treated as deterministic. Their stochastic variations greatly affect the forecasting of life and performance of the components. In this work, the main parameters considered affected by the uncertainty are the circumferential hot core location and the turbulence level at the inlet of the domain. A stochastic analysis is used to predict the degradation of a high-pressure-turbine (HPT) nozzle due to particulate ingestion. The GT’s component analyzed as a reference is the HPT nozzle of the Energy-Efficient Engine (E3). The uncertainty quantification technique used is the probabilistic collocation method (PCM). This work shows the impact of the operating conditions uncertainties on the performance and lifetime reduction due to deposition. Sobol indices are used to identify the most important parameter and its contribution to life. The present analysis enables to build confidence intervals on the deposit profile and on the residual creep-life of the vane.


2021 ◽  
Vol 13 (24) ◽  
pp. 13678
Author(s):  
Anton Petrochenkov ◽  
Aleksandr Romodin ◽  
Vladimir Kazantsev ◽  
Aleksey Sal’nikov ◽  
Sergey Bochkarev ◽  
...  

The purpose of the study is to analyze the prospects for the development of loading methods for gas turbines as well as to develop a mathematical model that adequately describes the real operating conditions of the loading system at various loads and rotation speeds. A comparative analysis of the most common methods and technical means of loading the shafts of a free turbine at gas turbine plants intended for operation as part of gas pumping units is presented. Based on the results of the analysis, the expediency of using the loading model “Free Power Turbine Rotor–Hydraulic Brake” as a load simulation is shown. Recommendations for the creation of an automation system for the load testing of power plants have been developed. Mathematical models and Hardware-in-the-Loop simulation models of power plants have been developed and tested. One of the most important factors that predetermine the effectiveness of the loading principle is the possibility of software implementation of the loading means using software control systems that provide the specified loading parameters of the gas turbine.


Sign in / Sign up

Export Citation Format

Share Document