Experimental and Analytical Study on the Operation Characteristics of the AHAT System

2012 ◽  
Vol 134 (5) ◽  
Author(s):  
Hidefumi Araki ◽  
Tomomi Koganezawa ◽  
Chihiro Myouren ◽  
Shinichi Higuchi ◽  
Toru Takahashi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Ambient Temperature ◽  
Gas Turbine ◽  
Thermal Efficiency ◽  
Pilot Plant ◽  
Temperature Effects ◽  
Operational Flexibility ◽  
Start Up ◽  
Air Turbine ◽  
Load Characteristics

Operational flexibility, such as faster start-up time or faster load change rate, and higher thermal efficiency, have become more and more important for recent thermal power systems. The advanced humid air turbine (AHAT) system has been studied to improve operational flexibility and thermal efficiency of the gas turbine power generation system. Advanced humid air turbine is an original system which substitutes the water atomization cooling (WAC) system for the intercooler system of the HAT cycle. A 3 MW pilot plant, which is composed of a gas turbine, a humidification tower, a recuperator and a water recovery system, was built in 2006 to verify feasibility of the AHAT system.In this paper, ambient temperature effects, part-load characteristics and start-up characteristics of the AHAT system were studied both experimentally and analytically. Also, change in heat transfer characteristics of the recuperator of the 3 MW pilot plant was evaluated from Nov. 2006 to Feb. 2010. Ambient temperature effects and part-load characteristics of the 3 MW pilot plant were compared with heat and material balance calculation results. Then, these characteristics of the AHAT and the combined cycle (CC) systems were compared assuming they were composed of mid-sized industrial gas turbines.The measured cold start-up time of the 3 MW AHAT pilot plant was about 60 min, which was dominated by the heat capacities of the plant equipment. The gas turbine was operated a total of 34 times during this period (Nov. 2006 to Feb. 2010), but no interannual changes were observed in pressure drops, temperature effectiveness, and the overall heat transfer coefficient of the recuperator.

Experimental and Analytical Study on the Operation Characteristics of the AHAT System

2011 ◽  
Author(s):  
Hidefumi Araki ◽  
Tomomi Koganezawa ◽  
Chihiro Myouren ◽  
Shinichi Higuchi ◽  
Toru Takahashi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Ambient Temperature ◽  
Gas Turbine ◽  
Thermal Efficiency ◽  
Pilot Plant ◽  
Temperature Effects ◽  
Operational Flexibility ◽  
Part Load ◽  
Start Up ◽  
Load Characteristics

Operational flexibility, such as faster start-up time or faster load change rate, and higher thermal efficiency, have become more and more important for recent thermal power systems. The AHAT (advanced humid air turbine) system has been studied to improve operational flexibility and thermal efficiency of the gas turbine power generation system. AHAT is an original system which substitutes the WAC (water atomization cooling) system for the intercooler system of the HAT cycle. A 3MW pilot plant, which is composed of a gas turbine, a humidification tower, a recuperator and a water recovery system, was built in 2006 to verify feasibility of the AHAT system. In this paper, ambient temperature effects, part-load characteristics and start-up characteristics of the AHAT system were studied both experimentally and analytically. Also, change in heat transfer characteristics of the recuperator of the 3MW pilot plant was evaluated from November 2006 to February 2010. Ambient temperature effects and part-load characteristics of the 3MW pilot plant were compared with heat and material balance calculation results. Then, these characteristics of the AHAT and the CC (combined cycle) systems were compared assuming they were composed of mid-sized industrial gas turbines. The measured cold start-up time of the 3MW AHAT pilot plant was about 60min, which was dominated by the heat capacities of the plant equipment. The gas turbine was operated a total of 34 times during this period (November 2006 to February 2010), but no interannual changes were observed in pressure drops, temperature effectiveness, and the overall heat transfer coefficient of the recuperator.

Test Results of 40MW-Class Advanced Humid Air Turbine and Exhaust Gas Water Recovery System

2014 ◽  
Author(s):  
Takuya Takeda ◽  
Hidefumi Araki ◽  
Yasushi Iwai ◽  
Tetsuro Morisaki ◽  
Kazuhiko Sato
Keyword(s):  
Gas Turbine ◽  
Test Facility ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Water Recovery ◽  
Test Results ◽  
Operational Flexibility ◽  
Start Up ◽  
Air Turbine ◽  
Recovery System

Operational flexibility, such as faster start-up time or faster load change rate, and higher thermal efficiency, have become more and more important for recent thermal power systems. The advanced humid air turbine (AHAT) system has been studied to improve operational flexibility and thermal efficiency of gas turbine power generation systems. A 40MW-class AHAT test facility was built and the rated output was achieved. Through operations at the facility, it has been verified for the first time that the key components of the medium-class gas turbines, such as an axial compressor and multi-can combustor, can be applied to the AHAT system. The cold start-up time from ignition to rated power was about 60 min, which is approximately one-third that of a conventional gas turbine combined cycle (GTCC) plant. NOx emissions were 24ppm (at 16% O2) when the humidity of combustion air was approximately a half that of present commercial AHAT plants, and NOx emissions in a future commercial AHAT system were thought to be less than 10ppm. A water recovery system which recovers water from a part of the exhaust gas of the 40MW-class test facility was built and test operations were made from June 2013. In this paper, water recovery test results as well as the 40MW-class gas turbine test results are shown.

Development of Elemental Technologies for Advanced Humid Air Turbine System

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Hidetoshi Kuroki ◽  
Shigeo Hatamiya ◽  
Takanori Shibata ◽  
Tomomi Koganezawa ◽  
Nobuaki Kizuka ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Pilot Plant ◽  
Pressure Ratio ◽  
High Humidity ◽  
Nox Emissions ◽  
Two Stage ◽  
Humid Air ◽  
Air Turbine ◽  
Recovery System

The advanced humid air turbine (AHAT) system improves the thermal efficiency of gas turbine power generation by using a humidifier, a water atomization cooling (WAC) system, and a heat recovery system, thus eliminating the need for an extremely high firing temperature and pressure ratio. The following elemental technologies have been developed to realize the AHAT system: (1) a broad working range and high-efficiency compressor that utilizes the WAC system to reduce compression work, (2) turbine blade cooling techniques that can withstand high heat flux due to high-humidity working gas, and (3) a combustor that achieves both low NOx emissions and a stable flame condition with high-humidity air. A gas turbine equipped with a two-stage radial compressor (with a pressure ratio of 8), two-stage axial turbine, and a reverse-flow type of single-can combustor has been developed based on the elemental technologies described above. A pilot plant that consists of a gas turbine generator, recuperator, humidification tower, water recovery system, WAC system, economizer, and other components is planned to be constructed, with testing slated to begin in October 2006 to validate the performance and reliability of the AHAT system. The expected performance is as follows: thermal efficiency of 43% (LHV), output of 3.6MW, and NOx emissions of less than 10ppm at 15% O2. This paper introduces the elemental technologies and the pilot plant to be built for the AHAT system.

Development of Elemental Technologies for Advanced Humid Air Turbine System

2006 ◽  
Author(s):  
Hidetoshi Kuroki ◽  
Takanori Shibata ◽  
Tomomi Koganezawa ◽  
Nobuaki Kizuka ◽  
Shigeo Hatamiya ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Pilot Plant ◽  
Pressure Ratio ◽  
High Humidity ◽  
Nox Emissions ◽  
Two Stage ◽  
Humid Air ◽  
Air Turbine ◽  
Recovery System

The Advanced Humid Air Turbine (AHAT) system improves the thermal efficiency of gas turbine power generation by using a humidifier, a Water Atomization Cooling (WAC) system, and a heat recovery system, thus eliminating the need for an extremely high firing temperature and pressure ratio. The following elemental technologies have been developed to realize the AHAT system: (1) a broad working range and high-efficiency compressor that utilizes the WAC system to reduce compression work, (2) turbine blade cooling techniques that can withstand high heat flux due to high-humidity working gas, and (3) a combustor that achieves both low NOx emissions and a stable flame condition with high-humidity air. A gas turbine equipped with a two-stage radial compressor (with a pressure ratio of 8), two-stage axial turbine, and a reverse-flow type of single-can combustor has been developed based on the elemental technologies described above. A pilot plant that consists of a gas turbine generator, recuperator, humidification tower, water recovery system, WAC system, economizer, and other components is planned to be constructed, with testing slated to begin in October 2006 to validate the performance and reliability of the AHAT system. The expected performance is as follows: thermal efficiency of 43% (LHV), output of 3.6 MW, and NOx emissions of less than 10 ppm at 15% O2. This paper introduces the elemental technologies and the pilot plant to be built for the AHAT system.

Test Results From the Advanced Humid Air Turbine System Pilot Plant: Part 1—Overall Performance

2008 ◽  
Author(s):  
Shinichi Higuchi ◽  
Tomomi Koganezawa ◽  
Yasuhiro Horiuchi ◽  
Hidefumi Araki ◽  
Takanori Shibata ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Pilot Plant ◽  
Pressure Ratio ◽  
High Humidity ◽  
Water Recovery ◽  
Two Stage ◽  
Humid Air ◽  
Air Turbine ◽  
Overall Performance

The AHAT (advanced humid air turbine) system is based on a recuperated cycle using high-humidity air. This system improves thermal efficiency by using the high-humidity air as working gas. After many studies and elemental tests, a 4MW-class pilot plant was planned and built in order to verify feasibility of the AHAT system from the viewpoints of heat cycle characteristic and engineering. This plant consists of a gas turbine, a recuperator, a humidification tower, a water recovery system, an economizer, and other components. The gas turbine consists of a two-stage centrifugal compressor (pressure ratio of 8), a reverse-flow type single-can combustor, and a two-stage axial-flow turbine. In overall performance tests, the plant thermal efficiency exceeded 40%LHV.

Staged Premix EV Combustion in Alstom’s GT24 Gas Turbine Engine

2012 ◽  
Author(s):  
Daniel Guyot ◽  
Thiemo Meeuwissen ◽  
Dieter Rebhan
Keyword(s):  
Gas Turbine ◽  
Distribution System ◽  
Fuel Oil ◽  
Operational Flexibility ◽  
Nox Formation ◽  
Diffusion Type ◽  
Fuel Gas ◽  
Start Up ◽  
Reduce Emissions ◽  
Ev Burner

Reducing gas turbine emissions and increasing their operational flexibility are key targets in today’s gas turbine market. In order to further reduce emissions and increase the operational flexibility of its GT24, Alstom has introduced an internally staged premix system into the GT24’s EV combustor. This system features a rich premix mode for GT start-up and a lean premix mode for GT loading and baseload operation. The fuel gas is injected through two premix stages, one injecting fuel into the burner air slots and one injecting fuel into the centre of the burner cone. Both premix stages are in continuous operation throughout the entire operating range, i.e. from ignition to baseload, thus eliminating the previously used pilot operation during start-up with its diffusion-type flame and high levels of NOx formation. The staged EV combustion concept is today a standard on the current GT26 and GT24. The EV burners of the GT26 are identical to the GT24 and fully retrofittable into existing GT24 engines. Furthermore, engines operating only on fuel gas (i.e. no fuel oil operation) no longer require a nitrogen purge and blocking air system so that this system can be disconnected from the GT. Only minor changes to the existing GT24 EV combustor and fuel distribution system are required. This paper presents validation results for the staged EV burner obtained in a single burner test rig at full engine pressure, and in a GT24 field engine, which had been upgraded with the staged EV burner technology in order to reduce emissions and extend the combustor’s operational behavior.

scholarly journals Method of coordinating air starter and auxiliary power unit joint operation

2020 ◽  
pp. 5-13
Author(s):  
Grigory Popov ◽  
◽  
Vasily Zubanov ◽  
Valeriy Matveev ◽  
Oleg Baturin ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Power Unit ◽  
Gas Turbine Engine ◽  
Working Process ◽  
Joint Operation ◽  
Turbine Engine ◽  
Auxiliary Power Unit ◽  
Auxiliary Power ◽  
Start Up ◽  
Air Turbine

The presented work provides a detailed description of the method developed by the authors for coordinating the working process of the main elements of the starting system for a modern gas turbine engine for a civil aviation aircraft: an auxiliary power unit (APU) and an air turbine – starter. This technique was developed in the course of solving the practical problem of selecting the existing APU and air turbine for a newly created engine. The need to develop this method is due to the lack of recommendations on the coordination of the elements of the starting system in the available literature. The method is based on combining the characteristics of the APU and the turbine, reduced to a single coordinate system. The intersection of the characteristic’s lines corresponding to the same conditions indicates the possibility of joint operation of the specified elements. The lack of intersection indicates the impossibility of joint functioning. The calculation also takes into account losses in the air supply lines to the turbine. The use of the developed method makes it possible to assess the possibility of joint operation of the APU and the air turbine in any operating mode. In addition to checking the possibility of functioning, as a result of the calculation, specific parameters of the working process at the operating point are determined, which are then used as initial data in calculating the elements of the starting system, for example, determining the parameters of the turbine, which in turn allow providing initial information for calculating the starting time or the possibility of functioning of the starting system GTE according to strength and other criteria. The algorithm for calculating the start-up time of the gas turbine engine was also developed by the authors and implemented in the form of an original computer program. Keywords: gas turbine engine start-up, GTE starting system, air turbine, methodology, joint work, auxiliary power unit, power, start-up time, characteristics matching, coordination, operational characteristics, computer program.

Influence of Steam Injection on Thermal Efficiency and Operating Temperature of GE-F5 Gas Turbines Applying VODOLEY System

2005 ◽  
Author(s):  
Mohsen Ghazikhani ◽  
Nima Manshoori ◽  
Davood Tafazoli
Keyword(s):  
Power Plant ◽  
Ambient Temperature ◽  
Gas Turbine ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Steam Injection ◽  
Gas Turbine Cycle

An industrial gas turbine has the characteristic that turbine output decreases on hot summer days when electricity demand peaks. For GE-F5 gas turbines of Mashad Power Plant when ambient temperature increases 1° C, compressor outlet temperature increases 1.13° C and turbine exhaust temperature increases 2.5° C. Also air mass flow rate decreases about 0.6 kg/sec when ambient temperature increases 1° C, so it is revealed that variations are more due to decreasing in the efficiency of compressor and less due to reduction in mass flow rate of air as ambient temperature increases in constant power output. The cycle efficiency of these GE-F5 gas turbines reduces 3 percent with increasing 50° C of ambient temperature, also the fuel consumption increases as ambient temperature increases for constant turbine work. These are also because of reducing in the compressor efficiency in high temperature ambient. Steam injection in gas turbines is a way to prevent a loss in performance of gas turbines caused by high ambient temperature and has been used for many years. VODOLEY system is a steam injection system, which is known as a self-sufficient one in steam production. The amount of water vapor in combustion products will become regenerated in a contact condenser and after passing through a heat recovery boiler is injected in the transition piece after combustion chamber. In this paper the influence of steam injection in Mashad Power Plant GE-F5 gas turbine parameters, applying VODOLEY system, is being observed. Results show that in this turbine, the turbine inlet temperature (T3) decreases in a range of 5 percent to 11 percent depending on ambient temperature, so the operating parameters in a gas turbine cycle equipped with VODOLEY system in 40° C of ambient temperature is the same as simple gas turbine cycle in 10° C of ambient temperature. Results show that the thermal efficiency increases up to 10 percent, but Back-Work ratio increases in a range of 15 percent to 30 percent. Also results show that although VODOLEY system has water treatment cost but by using this system the running cost will reduce up to 27 percent.

A Generalized Mathematical Model to Estimate Gas Turbine Starting Characteristics

1982 ◽  
Vol 104 (1) ◽  
pp. 194-201 ◽  
Author(s):  
R. K. Agrawal ◽  
M. Yunis
Keyword(s):  
Mathematical Model ◽  
Ambient Temperature ◽  
Gas Turbine ◽  
System Combination ◽  
Turbine Performance ◽  
Start Up ◽  
Starting Characteristics ◽  
Starting Torque

The paper describes a generalized mathematical model to estimate gas turbine performance in the starting regime of the engine. These estimates are then used to calculate the minimum engine starting torque requirements, thereby defining the specifications for the aircraft starting system. Alternatively, the model can also be used to estimate the start up time at any ambient temperature or altitude for a given engine/aircraft starting system combination.

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