Structural Analysis of a Gas Turbine Axial Compressor Blade Eroded by Online Water Washing

2021 ◽  
Author(s):  
Rossella Cinelli ◽  
Gianluca Maggiani ◽  
Serena Gabriele ◽  
Alessio Castorrini ◽  
Giuliano Agati ◽  
...  
Author(s):  
Rossella Cinelli ◽  
Gianluca Maggiani ◽  
Serena Gabriele ◽  
Alessio Castorrini ◽  
Giuliano Agati ◽  
...  

Abstract The Gas Turbine (GT) Axial Compressor (AXCO) can absorb up to the 30% of the power produced by the GT, being the component with the largest impact over the performances. The axial compressor blades might undergo the fouling phenomena as a consequence of the unwanted material locally accumulating during the machine operations. The presence of such polluting substances reduces the aerodynamic efficiency as well as the air intake causing the drop of performances and the increase of the fuel consumption. To address the above-mentioned critical issues, several washing strategies have been implemented so far, among the most promising ones, High Flow On-Line Water Washing (HFOLWW) is worth to mention. Exploiting this technique, the performance levels are preserved, whereas the stops for maintenance should be reduced. Nevertheless, this comes at the cost of a long-term erosion exposure caused by the impact of water washing droplets. Hence, it was deemed necessary to carry out a finite element method (FEM) structural analysis of the first rotor stage of the compressor of an aeroderivative GT, integrated into the HFOLWW scheme, in order to evaluate the fatigue strength of the component subjected to the erosion; possibly along with its acceptability limits. The first step requires the determination of the blade areas affected by erosion, using computational fluid dynamics (CFD) simulations, followed by the creation and the 3D modelling of the damaged geometry. The final step consists in the evaluation of the static stress and the dynamic agents, to perform a fatigue analysis through the Goodman relation and carrying out a simulation of damage propagation exploiting the theory of fracture mechanics. This procedure has been extended to the damage-free baseline component to set-up a model suitable for comparison. The structural analysis confirms the design of the blade, moreover dynamic and static evaluation of the eroded profiles haven’t outlined any working, nor mechanical, issue. This entitles the structural choice of HFOLWW as a system which guarantees full performance levels of the compressor.


Author(s):  
Ilaria Dominizi ◽  
Serena Gabriele ◽  
Angela Serra ◽  
Domenico Borello

Abstract Nowadays the climate change is widely recognized as a global threat by both public opinion and industries. Actions to mitigate its causes are gaining momentum within all industries. In the energy field, there is the necessity to reduce emissions and to improve technologies to preserve the environment. LCA analyses of products are fundamental in this context. In the present work, a life cycle assessment has been carried out to calculate the carbon footprint of different water washing processes, as well as their effectiveness in recovering Gas Turbine efficiency losses. Field data have been collected and analyzed to make a comparison of the GT operating conditions before and after the introduction of an innovative high flow online water washing technique. The assessments have been performed using SimaPro software and cover the entire Gas Turbine and Water Washing skids operations, including the airborne emissions, skid pump, the water treatment and the heaters.


Author(s):  
Klaus Brun ◽  
William C. Foiles ◽  
Terrence A. Grimley ◽  
Rainer Kurz

An investigation of the effectiveness of online combustion turbine axial compressor washing using various purity grade waters and commercial washing detergents was performed. For this project, blade surface fouling dirt was obtained from gas turbine axial compressor blades installed at various field sites. The dirt was analyzed to determine the composition and consistency of typical blade surface fouling materials. A representative dirt formula and blade coating procedure was developed so that comparative tests could be performed using various cleaning fluids. Dirt coated blades were installed in a wind tunnel capable of simulating compressor operating conditions. A spray nozzle upstream of the blade test section was used for washing blades with five different test liquids to determine the effectiveness or advantages of any liquid. Once this testing was completed, a similar test setup was then utilized to inject a mixture of formulated fouling dirt and the various online cleaning liquids upstream of the blade into the wind tunnel to assess redeposit characteristics. The effect of high-purity water versus regular water on fouling dirt was also studied in separate residue experiments. Results indicate that spraying cleaning fluid into a flowing air stream is a viable means of cleaning a compressor blade. Each of the fluids was able to clean the test blade at both low and high air velocities and at different blade incident angles. Within the parameters/fluids tested, the results indicate that: 1. The blade cleaning is primarily a mechanical function and does not depend on the type of fluid used for cleaning. The results showed that most of the cleaning occurs shortly after the cleaning fluid is introduced into the flow stream. 2. Dirt removed from the blades may redeposit in other areas as the cleaning fluid is evaporated. Redeposit occurred in flow recirculation zones during the cleaning tests, and heated flow tests demonstrated dirt deposit in the presence of a cleaning fluid. In addition, the type of fluid used for cleaning has no effect on the redeposit characteristics of the dirt. 3. Blade erosion was not found to be a significant issue for the short durations that online water-washing was performed. However, uncontrolled water-washing (or overspray) for extended periods of time did result in measureable leading and trailing edge blade erosions.


Author(s):  
Klaus Brun ◽  
Terrence A. Grimley ◽  
William C. Foiles ◽  
Rainer Kurz

An investigation of the effectiveness of online combustion turbine axial compressor washing using various purity grade waters and commercial washing detergents was performed. For this project, blade surface fouling dirt was obtained from gas turbine axial compressor blades installed at various field sites. The dirt was analyzed to determine consistency of typical blade surface fouling materials. A representative dirt formula and blade coating procedure was developed so that comparative tests could be performed using various cleaning fluids. Dirt coated blades were installed in a wind tunnel capable of simulating compressor operating conditions. A spray nozzle upstream of the blade test section was used for washing blades with five different test liquids to determine the effectiveness or advantages of any liquid. Once this testing was completed, a similar test setup was then utilized to inject a mixture of formulated fouling dirt and the various online cleaning liquids upstream of the blade into the wind tunnel to assess redeposit characteristics. The effect of high-purity water versus regular water on fouling dirt was also studied in separate residue experiments. Results indicate that spraying cleaning fluid into a flowing air stream is a viable means of cleaning a compressor blade. Each of the fluids was able to clean the test blade at both low and high air velocities and at different blade incident angles. Within the parameters/fluids tested, the results indicate that: (1) The blade cleaning is primarily a mechanical function and does not depend on the type of fluid used for cleaning. The results showed that most of the cleaning occurs shortly after the cleaning fluid is introduced into the flow stream. (2) Dirt removed from the blades may redeposit in other areas as the cleaning fluid is evaporated. Redeposit occurred in flow recirculation zones during the cleaning tests, and heated flow tests demonstrated dirt deposit in the presence of a cleaning fluid. In addition, the type of fluid used for cleaning has no effect on the redeposit characteristics of the dirt. (3) Blade erosion was not found to be a significant issue for the short durations that online water-washing was performed. However, uncontrolled water-washing (or overspray) for extended periods of time did result in measureable leading and trailing edge blade erosions.


2019 ◽  
pp. 21-30 ◽  
Author(s):  
Людмила Георгиевна Бойко ◽  
Вадим Анатольевич Даценко ◽  
Наталия Владимировна Пижанкова

The results of mathematical modeling processes in the turboshaft gas turbine engine (GTE) are presented. The using calculation method based on a high-level GTE mathematical model, which is founded on a multi-stage axial compressor blade-to-blade description. The model was developed at the Aviation Theory Chair of National Aerospace University “KhAI”. The model is based on a multistage axial compressor thermodynamic parameters calculations using a 1D and 2D approaches to analyzing of the flow. The model named above allows one to take into account air intakes from of the compressor blade gaps, as well as adjusting the angles of installation of the rotary stator vanes depending on the rotational speed. The GTE model has a modular structure. To determine the compressor parameters the modules for 1D or 2D flow calculation can be connected. As the initial data, besides the data traditionally specified in the 1st level GTE models it is necessary to set the geometrical parameters of the compressor flow path and blades on the medium radius (for the 2nd level GTE model) or along with the blade height (for the 3rd level). Both calculating compressor parameters methods are verified and have a fairly wide experience of practical use. The article presents the results of calculating the maps of the GTE multi-stage compressor using one- and two-dimensional approaches. Comparison of the compressor performances achieved by using of these two methods among themselves and with the experimental data has shown their good agreement. The approach used to simulate the flow in compressors makes it possible to estimate, by calculation, the surge margin, to consider the incidence angles and other flow parameters in the blade gaps in a wide range of GTE operation modes. Such results, as well as a comparison with experimental data, are presented in the article. The article also demonstrates the results of applying the described above model to the gas turbine engine performances calculation. The engine has the 12-stage axial compressor with the stator blades position of the first stages regulation. The calculated line of joint operation modes of the gas generator units, the dependence of the power and specific fuel consumption on the rotational speed. Presented are the processes in GTE on stationary modes analyzing results given in the article showed the used model advantage, reliability and expediency of its practical application.


Author(s):  
Edward M. House

Four Textron Lycoming TF40B marine gas turbine engines are used to power the U.S. Navy’s Landing Craft Air Cushion (LCAC) vehicle. This is the first hovercraft of this configuration to be put in service for the Navy as a landing craft. The TF40B has experienced compressor blade pitting, carbon erosion of the first turbine blade and hot corrosion of the hot section. Many of these problems were reduced by changing the maintenance and operation of the LCAC. A Component Improvement Program (CIP) is currently investigating compressor and hot section coatings better suited for operation in a harsh marine environment. This program will also improve the performance of some engine components such as the bleed manifold and bearing seals.


Author(s):  
M. Bianchi ◽  
F. Melino ◽  
A. Peretto ◽  
P. R. Spina ◽  
S. Ingistov

In the last years, among all different gas turbine inlet air cooling techniques, an increasing attention to fogging approach is dedicated. The various fogging strategies seem to be a good solution to improve gas turbine or combined cycle produced power with low initial investment cost and less installation downtime. In particular, overspray fogging and interstage injection involve two-phase flow consideration and water evaporation during compression process (also known as wet compression). According to the Author’s knowledge, the field of wet compression is not completely studied and understood. In the present paper, all the principal aspects of wet compression and in particular the influence of injected water droplet diameter and surface temperature, and their effect on gas turbine performance and on the behavior of the axial compressor (change in axial compressor performance map due to the water injection, redistribution of stage load, etc.) are analyzed by using a calculation code, named IN.FO.G.T.E. (INterstage FOgging Gas Turbine Evaluation), developed and validated by the Authors.


Sign in / Sign up

Export Citation Format

Share Document