Influence of Water Droplet Size and Temperature on Wet Compression

2007 ◽  
Author(s):  
M. Bianchi ◽  
F. Melino ◽  
A. Peretto ◽  
P. R. Spina ◽  
S. Ingistov
Keyword(s):  
Gas Turbine ◽  
Water Droplet ◽  
Droplet Diameter ◽  
Axial Compressor ◽  
Combined Cycle ◽  
Water Evaporation ◽  
Air Cooling ◽  
Compression Process ◽  
Two Phase ◽  
Wet Compression

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.

A Parametric Study of Interstage Injection on GE Frame 7EA Gas Turbine

2004 ◽  
Author(s):  
M. Bagnoli ◽  
M. Bianchi ◽  
F. Melino ◽  
A. Peretto ◽  
P. R. Spina ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Axial Compressor ◽  
Combined Cycle ◽  
Water Evaporation ◽  
Air Cooling ◽  
Phase Flow ◽  
Compression Process ◽  
Two Phase ◽  
Wet Compression ◽  
Flow Compression

In recent years, among various available inlet air cooling techniques for gas turbine power enhancement, high pressure fogging has seen an increasing attention mainly because of its comparatively low initial investment cost and less downtime for its installation. The various fogging strategies such as inlet evaporative, overspray (or wet compression) and interstage injection have been implemented in simple and combined cycle applications. Unlike wet compression, air at the compressor inlet is not fully saturated with the interstage injection. However, both wet compression and interstage injection involve multi-phase flow and water evaporation during the compression process. The phenomenon of two phase flow compression in axial compressor is not yet fully understood. This paper investigates effects of interstage injection on the performance of a GE Frame 7EA gas turbine using aero-thermodynamic modeling. In addition to estimating the overall gas turbine performance changes achievable with the interstage injection approach, the study presented here discusses impact of interstage injection on the stage-by-stage compressor performance characteristics of the selected gas turbine. The plausible reasons for the observed performance changes are discussed.

Influence of Compressor Performance Maps Shape on Wet Compression

2008 ◽  
Author(s):  
Rakesh K. Bhargava ◽  
Michele Bianchi ◽  
Francesco Melino ◽  
Antonio Peretto ◽  
Pier Ruggero Spina
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Axial Compressor ◽  
Combined Cycle ◽  
Water Evaporation ◽  
Compression Process ◽  
Two Phase ◽  
Compressor Performance ◽  
Wet Compression ◽  
Calculation Code

In recent years, a great number of studies were carried out in order to analyze the main features of fogging technologies. The various fogging strategies seem to improve gas turbine and combined cycle power output with low initial investment cost and less installation downtime. In fact, nowadays fogging is successfully installed on several gasturbine and combined cycle power plants worldwide. In particular, overspray fogging and interstage injection involve two-phase flow consideration and water evaporation during compression process (also known as wet compression). The aim of the present paper is to further improve understanding of the wet compression process including stage-by-stage compressor behavior by investigating the influence of the axial compressor performance map shape on the evaporation process of the injected water through the compressor, achievable power boost, the maximum amount of water which can be injected and/or influence on the surge conditions. This analysis is carried out by using a calculation code, named IN.FO.G.T.E. (INterstage FOgging Gas Turbine Evaluation), developed and validated by the Authors.

Effects of Wet Compression on the Flow Behavior of a Centrifugal Compressor: A CFD Analysis

2014 ◽  
Author(s):  
Anish Surendran ◽  
Heuy Dong Kim
Keyword(s):  
Flow Rate ◽  
Water Droplet ◽  
Evaporation Rate ◽  
Pressure Ratio ◽  
Phase Flow ◽  
Water Droplets ◽  
Compression Process ◽  
Two Phase ◽  
Wet Compression ◽  
Injection Ratio

Wet compression has been emerging as a prominent method for augmenting net power output from land based gas turbine engine. It is proven more effective than the conventional inlet cooling methods. In this method, fine water droplets are injected just upstream of the compressor impeller. These water droplets absorb the latent heat of evaporation during the compression process of gas-water droplet two-phase flow, consequently reducing the temperature rise. Many gas turbine engineers have performed the feasibility and usefulness studies on this wet compression, but physical understanding on the wet compression process is highly lacking, and related compression flow mechanism remains ambiguous. In the present study, a computational fluid dynamics method has been applied to investigate the wet compression effects on a low speed centrifugal compressor. A Langrangian particle tracking method was employed to simulate the air-water droplet two-phase flow. The power saving achieved with different injection ratio of water droplets has been calculated and it is found that significant saving can be obtained with a water droplet injection ratio of above 3%. The vapor mass fraction varies linearly along the streamwise direction, making the assumption for a constant evaporation rate is valid. With the increase in the injection ratio the polytropic index for compression is coming down. The diffuser pressure recovery has been improved significantly with the wet compression; while the total pressure ratio across the impeller does not improve much. Contrary to the expectation, the evaporation rate is found to be coming down with the increase in the compressor mass flow rate. It is observed that the operating point, at which the peak pressure ratio occurs, shift towards higher mass flow rate during wet compression due to the local recirculation region within the vaneless space between the impeller and diffuser.

scholarly journals A New Gas Turbine Cycle for Economical Power Boosting

1997 ◽  
Author(s):  
Motoaki Utamura ◽  
Isao Takehara ◽  
Nobuyuki Horii ◽  
Takaaki Kuwahara
Keyword(s):  
Gas Turbine ◽  
Water Consumption ◽  
Power Output ◽  
Water Droplet ◽  
Cooling System ◽  
Axial Flow ◽  
Water Evaporation ◽  
Air Cooling ◽  
Efficient Manner ◽  
Air Cooling System

A Moisture Air Turbine (MAT) cycle is proposed for improving the characteristics of land based gas turbine by injecting atomized water at inlet to compressor. The power boosting mechanism of MAT is understood as composits of those of following existing systems: inlet air cooling system, inter-cooling and steam injection. Experiments using a 15MW class axial flow load compressor have been carried out to reveal that water evaporation in compressor could reduce compressor work in an efficient manner. Moreover, this technology has been demonstrated by means of 130MW class simple cycle gas turbine power plant to show that a small amount of water consumption is sufficient to increase power output. Very efficient evaporation could be achieved provided the size of water droplet is controlled properly. The amount of water consumption is much less than that of conventional inlet air cooling system with cooling tower for heat rejection. Incorporating water droplet evaporation profile into consideration, realistic cycle calculation model has been developed to predict power output with water injection. It has been shown that this technology is economically achievable. It should be stressed that contrary to well known evaporative cooler, MAT cycle could provide power output at a desired value within its capability regardless of ambient humidity condition.

Thermodynamic Analyses of Wet Compression Process in the Compressor of Gas Turbine

2002 ◽  
Author(s):  
Qun Zheng ◽  
Yufeng Sun ◽  
Shuying Li ◽  
Yunhui Wang
Keyword(s):  
Gas Turbine ◽  
Thermodynamic Model ◽  
Water Droplet ◽  
Evaporative Cooling ◽  
Process Water ◽  
Water Droplets ◽  
Compression Process ◽  
Compression Efficiency ◽  
Wet Compression

Thermodynamic model of wet compression process is established in this paper. The topics of ideal wet compression process, actual wet compression process, water droplet evaporative rate, wet compression work, inlet evaporative cooling, concept of wet compression efficiency, aerodynamic breaking of water droplets etc. are investigated and discussed in this paper.

Thermodynamic Analyses of Wet Compression Process in the Compressor of Gas Turbine

2003 ◽  
Vol 125 (3) ◽  
pp. 489-496 ◽  
Author(s):  
Qun Zheng ◽  
Yufeng Sun ◽  
Shuying Li ◽  
Yunhui Wang
Keyword(s):  
Gas Turbine ◽  
Thermodynamic Model ◽  
Water Droplet ◽  
Evaporative Cooling ◽  
Process Water ◽  
Water Droplets ◽  
Compression Process ◽  
Compression Efficiency ◽  
Wet Compression

Thermodynamic model of wet compression process is established in this paper. The topics of ideal wet compression process, actual wet compression process, water droplet evaporative rate, wet compression work, inlet evaporative cooling, concept of wet compression efficiency, aerodynamic breaking of water droplets etc. are investigated and discussed in this paper.

Blading Heat Transfer Considerations in a Reheat-Gas-Turbine Combined Cycle

1981 ◽  
Author(s):  
P. E. Jenkins ◽  
I. G. Rice
Keyword(s):  
Heat Transfer ◽  
Gas Turbine ◽  
Steam Injection ◽  
Combined Cycle ◽  
Future Research ◽  
Air Cooling ◽  
Two Phase ◽  
Cooling Fluid ◽  
Cycle System ◽  
Transfer Equations

A brief presentation of the basic heat transfer equations for blade cooling is presented. Various cooling schemes have been developed over the past twenty years utilizing air as the cooling fluid. The mathematical models have subsequently predicted cooling schemes for the air cooling with little consideration for two phase fluids. This paper is written to describe the research needs for utilizing steam as a cooling fluid in a reheat-gas-turbine combined cycle system. The basic heat transfer equations are derived and discussed with regard to implementing the steam blanket cooling mechanism. The steam injection and dispersion problem is discussed, along with the need for future research in using steam as a viable cooling technique.

Fog System Performance in Power Augmentation of Heavy Duty Power Generating Gas Turbines Model 7EA

2000 ◽  
Author(s):  
Steve Ingistov
Keyword(s):  
Gas Turbines ◽  
Cooling System ◽  
Axial Compressor ◽  
Ambient Air ◽  
Water Mist ◽  
Water Evaporation ◽  
Air Cooling ◽  
Evaporation Process ◽  
Ambient Conditions ◽  
Compression Process

Ambient air temperature plays significant role in performance of a Gas Turbine. Frequently Gas Turbines in electrical power generation are single rotor and are directly coupled to the Electrical Generators. These machines normally operate 8,000 hours per calendar year under the 100% load. The control of the combustion air flow is achieved by modulating compressor Inlet Guide Vanes (IGV). The single shaft axial compressor consumes as a rule of thumb more than 50% of turbine useful expansion work. Axial compressor is high-volume, moderate discharge pressure machine. Its power demand to discharge ambient air to the turbine combustion system is very dependent on ambient conditions such as pressure, temperature and relative humidity. The optimization of the axial compressor aerodynamic loading under various ambient conditions is therefore mandatory. During the hot and humid summer days, especially from the noon time to 6:00 PM, the demand for the power is at its maximum. This Paper describes selection, design and installation of the Inlet Air Cooling System. (IACS). The selected IACS is fine water mist, FOG. FOG System (FS) was selected because of its efficiency and because the clean water was available. FS incorporates Fog Generating Skid (FGS) and Fog Curtain (FC). FC is comprised of lateral lines with equally spaced. FOG Nozzles (FN). The FN is specially designed to generate individual “Fog Cones” that efficiently dissipate the water particles in the space. Fine water particles are atomized by incoming air in the Inlet Air (IA) duct. The homogenous mixture of FOG and IA is required to enhance the water mist particles evaporation process. In cases when the FS works in tandem with Evaporative Cooler (EC) most of the FOG particles are “injected” into the compressor suction. The injected FOG particles start to evaporate during the IA compression process. The water evaporation process simultaneously causes cooling of the IA being compressed. The result is reduced compression work and improved performance of GT.

An Assessment of Wet Compression Process in Gas Turbine Systems with an Analytical Modeling

2012 ◽  
Vol 234 ◽  
pp. 23-27
Author(s):  
Kyoung Hoon Kim ◽  
Dong Joo Kim ◽  
Kyoung Jin Kim ◽  
Seong Wook Hong
Keyword(s):  
Gas Turbine ◽  
Analytical Modeling ◽  
High Efficiency ◽  
Water Injection ◽  
Transient Behavior ◽  
Combined Cycle ◽  
Specific Power ◽  
Outlet Temperature ◽  
Compression Process ◽  
Wet Compression

Recently humidified gas turbine systems in which water or steam is injected have attracted much attention, since they can offer a high efficiency and a high specific power with a relatively low cost compared to combined-cycle gas turbine systems, and therefore they have a potential for future power generation. In this study, performance analysis of the wet compression process is carried out with an analytical modeling which was developed from heat and mass transfer, and thermodynamic analyses based on droplet evaporation. Wet compression variables such as temperature-averaged polytropic coefficient, compressor outlet temperature, and compression work are estimated. Parametric studies show the effect of system parameters such as droplet size, water injection ratio or compression ratio on transient behavior.

Advanced and Transformational Hydrogen Turbines for Integrated Gasification Combined Cycles

2016 ◽  
Author(s):  
Walter W. Shelton ◽  
Robin W. Ames ◽  
Richard A. Dennis ◽  
Charles W. White ◽  
John E. Plunkett ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Carbon Capture ◽  
Combined Cycle ◽  
Plant Performance ◽  
System Level ◽  
Inlet Temperature ◽  
Air Cooling ◽  
Reference Case ◽  
Advanced Technologies ◽  
Integrated Gasification

The U.S. Department of Energy’s (DOE) provides a worldwide leadership role in the development of advanced fossil fuel-based energy conversion technologies, with a focus on electric power generation with carbon capture and storage (CCS). As part of DOE’s Office of Fossil Energy, the National Energy Technology Laboratory (NETL) implements research, development, and demonstration (RD&D) programs that address the challenges of reducing greenhouse gas emissions. To meet these challenges, NETL evaluates advanced power cycles that will maximize system efficiency and performance, while minimizing CO2 emissions and the costs of CCS. NETL’s Hydrogen Turbine Program has sponsored numerous R&D projects in support of Advanced Hydrogen Turbines (AHT). Turbine systems and components targeted for development include combustor technology, materials research, enhanced cooling technology, coatings development, and more. The R&D builds on existing gas turbine technologies and is intended to develop and test the component technologies and subsystems needed to validate the ability to meet the Turbine Program goals. These technologies are key components of AHTs, which enable overall plant efficiency and cost of electricity (COE) improvements relative to an F-frame turbine-based Integrated Gasification Combined Cycle (IGCC) reference plant equipped with carbon capture (today’s state-of-the-art). This work has also provided the basis for estimating future IGCC plant performance based on a Transformational Hydrogen Turbine (THT) with a higher turbine inlet temperature, enhanced material capabilities, reduced air cooling and leakage, and higher pressure ratios than the AHT. IGCC cases from using system-level AHT and THT gas turbine models were developed for comparisons with an F-frame turbine-based IGCC reference case and for an IGCC pathway study. The IGCC pathway is presented in which the reference case (i.e. includes F-frame turbine) is sequentially-modified through the incorporation of advanced technologies. Advanced technologies are considered to be either 2nd Generation or Transformational, if they are anticipated to be ready for demonstration by 2025 and 2030, respectively. The current results included the THT, additional potential transformational technologies related to IGCC plant sections (e.g. air separation, gasification, gas cleanup, carbon capture, NOx reduction) are being considered by NETL and are topics for inclusion in future reports.

Sign in / Sign up

Export Citation Format

Share Document