Time-Dependent Deposition Characteristics of Fine Coal Flyash in a Laboratory Gas Turbine Environment

2011 ◽  
Author(s):  
Robert G. Laycock ◽  
Thomas H. Fletcher
Keyword(s):  
Surface Temperature ◽  
Gas Turbine ◽  
Gas Flow ◽  
Coal Fly Ash ◽  
Time Dependent ◽  
Gas Temperature ◽  
Brigham Young University ◽  
Fine Coal ◽  
Two Samples ◽  
Nickel Base

Time-dependent deposition characteristics of fine coal flyash were measured in the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University. Two samples of subbituminous coal fly ash, with mass mean diameters of 3 and 13 μm, were entrained in a hot gas flow with a gas temperature of 1250°C and Mach number of 0.25. A nickel base super alloy metal coupon approximately 0.3 cm thick was held in a hot particle-laden gas stream to simulate deposition in a gas turbine. Tests were conducted with deposition times of 20, 40, and 60 minutes. Capture efficiencies and surface roughness characteristics (e.g., Ra) were obtained at different times. Capture efficiency increased exponentially with time while Ra increased linearly with time. The increased deposition with time caused the surface temperature of the deposit to increase. The increased surface temperature caused more softening, increasing the propensity for impacting particles to stick to the surface. These data are important for improving models of deposition in turbines from syngas flows.

Time-Dependent Deposition Characteristics of Fine Coal Fly Ash in a Laboratory Gas Turbine Environment

2012 ◽  
Vol 135 (2) ◽  
Author(s):  
Robert G. Laycock ◽  
Thomas H. Fletcher
Keyword(s):  
Fly Ash ◽  
Surface Temperature ◽  
Gas Turbine ◽  
Gas Flow ◽  
Coal Fly Ash ◽  
Time Dependent ◽  
Gas Temperature ◽  
Brigham Young University ◽  
Fine Coal ◽  
Two Samples

Time-dependent deposition characteristics of fine coal fly ash were measured in the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University. Two samples of subbituminous coal fly ash, with mass mean diameters of 3 μm and 13 μm, were entrained in a hot gas flow with a gas temperature of 1288 °C and Mach number of 0.25. A nickel-based, superalloy metal coupon approximately 0.3 cm thick was held in a hot particle-laden gas stream to simulate deposition in a gas turbine. Tests were conducted with deposition times of 20, 40, and 60 min. Capture efficiencies and surface roughness characteristics (e.g., Ra) were obtained at different times. Capture efficiency increased exponentially with time, while Ra increased linearly with time. The increased deposition with time caused the surface temperature of the deposit to increase. The increased surface temperature caused more softening, increasing the propensity for impacting particles to stick to the surface. These data are important for improving models of deposition in turbines from syngas flows.

Independent Effects of Surface and Gas Temperature on Coal Fly Ash Deposition in Gas Turbines at Temperatures up to 1400 °C

2015 ◽  
Vol 138 (2) ◽  
Author(s):  
Robert Laycock ◽  
Thomas H. Fletcher
Keyword(s):  
Fly Ash ◽  
Surface Temperature ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Particle Deposition ◽  
Coal Fly Ash ◽  
Combined Cycle ◽  
Capture Efficiency ◽  
Gas Temperature ◽  
Independent Effects

Deposition of coal fly ash in gas turbines has been studied to support the concept of integrated gasification combined cycle (IGCC). Although particle filters are used in IGCC, small amounts of ash particles less than 5 μm in diameter enter the gas turbine. Previous deposition experiments in the literature have been conducted at temperatures up to about 1288 °C. However, few tests have been conducted that reveal the independent effects of gas and surface temperature, and most have been conducted at gas temperatures lower than 1400 °C. The independent effects of gas and surface temperature on particle deposition in a gas turbine environment were measured using the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University. Gas temperatures were measured with a type K thermocouple and surface temperatures were measured with two-color pyrometry. This facility was modified for testing at temperatures up to 1400 °C. Subbituminous coal fly ash, with a mass mean diameter of 4 μm, was entrained in a hot gas flow at a Mach number of 0.25. A nickel base super alloy metal coupon 2.5 cm in diameter was held in this gas stream to simulate deposition in a gas turbine. The gas temperature (and hence particle temperature) governs the softening and viscosity of the particle, while the surface temperature governs the stickiness of the deposit. Two test series were therefore conducted. The first series used backside cooling to hold the initial temperature of the deposition surface (Ts,i) constant at 1000 °C while varying the gas temperature (Tg) from 1250 °C to 1400 °C. The second series held Tg constant at 1400 °C while varying Ts,i from 1050 °C to 1200 °C by varying the amount of backside cooling. Capture efficiency and surface roughness were calculated. Capture efficiency increased with increasing Tg. Capture efficiency also initially increased with Ts,i until a certain threshold temperature where capture efficiency began to decrease with increasing Ts,i.

Rosenhain Centenary Conference - 3. Materials development present and future 3.8. Nickel base materials developments for high temperatures

1976 ◽  
Vol 282 (1307) ◽  
pp. 389-399 ◽  
Keyword(s):  
Gas Turbine ◽  
High Temperatures ◽  
Gas Turbines ◽  
Age Hardening ◽  
Physical Metallurgy ◽  
Gas Temperature ◽  
Alloy Development ◽  
Materials Development ◽  
Base Materials ◽  
Nickel Base

The purpose of this paper is to review the development of nickel base alloys for service at high temperatures with particular reference to their use in gas turbines. Although the development has included a broad range of alloys designed for a variety of service conditions, it is characterized by the family of age-hardening compositions known as the ‘superalloys’. Other papers in the conference will be devoted to the contribution which these alloys have made to the gas turbine industry. Nonetheless, it is worth remarking here that improvements in the physical metallurgy and processing of the superalloys have made possible an average increase of 10 K per year in operating temperature over the last 35 years; a record unmatched by any other alloy development. When added to the increased gas temperature made possible by integral cooling of components in the turbine, itself greatly assisted by developments in the metallurgy of fabrication and casting, it is not surprising that the engineer has been able to transform the gas turbine from a curiosity into one of the fundamental power generating machines in a period of about 30 years.

scholarly journals Observations of Flame Behavior From a Practical Fuel Injector Using Gaseous Fuel in a Technology Combustor

1994 ◽  
Author(s):  
Paul O. Hedman ◽  
Geoffrey J. Sturgess ◽  
David L. Warren ◽  
Larry P. Goss ◽  
Dale T. Shouse
Keyword(s):  
Gas Turbine ◽  
Air Force ◽  
Diffusion Flames ◽  
Fuel Injector ◽  
Gas Temperature ◽  
Brigham Young University ◽  
Lean Blowout ◽  
Reaction Zones ◽  
Air Force Base ◽  
Whitney Aircraft

This paper presents results from an Air Force program being conducted by researchers at Brigham Young University (BYU) Wright-Patterson Air Force Base (WPAFB), and Pratt and Whitney Aircraft Co (P&W). This study is part of a comprehensive effort being supported by the Aero Propulsion and Power Laboratory at Wright-Patterson Air Force Base, and Pratt and Whitney Aircraft, Inc. in which simple and complex diffusion flames are being studied to better understand the fundamentals of gas turbine combustion near lean blowout. The program’s long term goal is to improve the design methodology of gas turbine combustors. This paper focuses on four areas of investigation: 1) digitized images from still film photographs to document the observed flame structures as fuel equivalence ratio was varied, 2) sets of LDA data to quantify the velocity flow fields existing in the burner, 3) CARS measurements of gas temperature to determine the temperature field in the combustion zone, and to evaluate the magnitude of peak temperature, and 4) two-dimensional images of OH radical concentrations using PLIF to document the instantaneous location of the flame reaction zones.

scholarly journals CARS Temperature and LDA Velocity Measurements in a Turbulent, Swirling, Premixed Propane/Air Fueled Model Gas Turbine Combustor

1995 ◽  
Author(s):  
Stephan E. Schmidt ◽  
Paul O. Hedman
Keyword(s):  
South Carolina ◽  
Gas Turbine ◽  
High Efficiency ◽  
Flame Structure ◽  
Gas Temperature ◽  
Velocity Measurements ◽  
Turbine Engine ◽  
Engineering Research ◽  
Brigham Young University ◽  
Systems Research

This paper present results from a research program being conducted at the Advanced Combustion Engineering Research Center (ACERC) at Brigham Young University (BYU). This study is part of a comprehensive effort supported by the Advanced Gas Turbine Systems Research (ATS) Program headquartered at the South Carolina Energy Research and Development Center, Clemson, South Carolina. The objective of this study was to characterize a turbulent premixed propane/air flame in a model combustor that simulates the characteristics of a utility gas turbine engine. The program’s long term goal is to develop and commercialize ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for base-load applications in the utility, independent power producer, and industrial markets. This paper focuses on the following four areas of the investigation: 1) a series of digitized video images to document the effect of fuel equivalence ratio and swirl number on flame structure, 2) LDA velocity measurements to quantify the flow structure, 3) CARS gas temperature measurements to determine the temperature field in the combustor, and 4) local continuity and energy release in differential elements throughout the flame zone.

Independent Effects of Surface and Gas Temperature on Coal Flyash Deposition in Gas Turbines at Temperatures Up to 1400°C

2015 ◽  
Author(s):  
Robert Laycock ◽  
Thomas H. Fletcher
Keyword(s):  
Surface Temperature ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Particle Deposition ◽  
Particle Temperature ◽  
Combined Cycle ◽  
Capture Efficiency ◽  
Threshold Temperature ◽  
Gas Temperature ◽  
Independent Effects

Deposition of coal flyash in gas turbines has been studied to support the concept of integrated gasification combined cycle (IGCC). Although particle filters are used in IGCC, small amounts of ash particles less than 5 μm diameter enter the gas turbine. Previous deposition experiments in the literature have been conducted at temperatures up to about 1288°C. However, few tests have been conducted that reveal the independent effects of gas and surface temperature, and most have been conducted at gas temperatures lower than 1400°C. The independent effects of gas and surface temperature on particle deposition in a gas turbine environment were measured using the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University. Gas temperatures were measured with a type K thermocouple and surface temperatures were measured with two-color pyrometry using the RGB signals from a camera. This facility was modified for testing at temperatures up to 1400°C. Subbituminous coal fly ash, with a mass mean diameter of 4 μm, was entrained in a hot gas flow at a Mach number of 0.25. A nickel base super alloy metal coupon 2.5 cm in diameter was held in this gas stream to simulate deposition in a gas turbine. The gas temperature (and hence particle temperature) governs the softening and viscosity of the particle, while the surface temperature governs the stickiness of the deposit. Two tests series were therefore conducted. The first series used backside cooling to hold the initial temperature of the deposition surface (Ts,i) constant at 1000°C while varying the gas temperature (Tg) from 1250°C – 1400°C. The second series held Tg constant at 1400°C while varying the initial Ts,i from 1050°C to 1200°C by varying the amount of backside cooling. Capture efficiency and surface roughness were calculated. Capture efficiency increased with increasing Tg. Capture efficiency also initially increased with Ts,i until a certain threshold temperature where capture efficiency began to decrease with increasing Ts,i.

scholarly journals Gas-Turbine Loading Schedule for Maximum Life of the Hot Gas Path Components

1970 ◽  
Author(s):  
Stanislaw Bednarski ◽  
C. N. Shen
Keyword(s):  
Plastic Strain ◽  
Thermal Shock ◽  
Gas Turbine ◽  
Firing Temperature ◽  
Thermal Fatigue ◽  
Computational Procedure ◽  
Time Dependent ◽  
Gas Temperature ◽  
Hot Gas ◽  
Loading Process

The paper describes development of a computational procedure for determining the optimal firing temperature schedule during loading of the gas turbine. It is assumed that the temperature has to be increased in a pre-determined time in a way that will minimize thermal fatigue deterioration of the turbine hot gas path elements. The gas temperature is constrained to lie between certain time-dependent limits all through the transient. The maximum plastic strain in a given loading process is taken as a measure of parts deterioration. The calculations performed are for hollow, stationary airfoils of a gas turbine, but the method is easily adaptable to full profiles and rotational airfoils as well as non-turbine applications where temperature is to be altered while thermal shock is to be minimized. A numerical example is given for illustration of the method.

scholarly journals Control of characteristics of closed gas turbine plants of submarines propulsion complexes

2021 ◽  
pp. 66-70
Author(s):  
В.Т. Матвеенко ◽  
А.В. Дологлонян ◽  
В.А. Очеретяный
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Gas Flow ◽  
The Arctic ◽  
Specific Power ◽  
Gas Temperature ◽  
Operating Cycle ◽  
Turbine Engine ◽  
Heat Regeneration ◽  
Effective Efficiency

Подводная техника особенно нужна при работе и снабжении подводными судами объектов на Арктическом шельфе вдоль Северного морского пути, связанного с преодолением ледовых полей. Среди различных типов энергетических установок для подводной техники перспективны замкнутые газотурбинные установки (ЗГТУ), способные в одноконтурном варианте работать на углеводородных типах топлива. В качестве окислителя можно использовать воздух, который на судах можно хранить в сжатом виде. В этом случае не нужна специальная береговая инфраструктура, ограничивающая дальность плавания подводной техники. За основу базовой схемы ЗГТУ принят газотурбинный двигатель (ГТД) с регенерацией (Р) теплоты, как более экономичный по сравнению с ГТД простого цикла, и схемы которого характерны для микрогазотурбинных двигателей. Также рассмотрены ЗГТУ с турбокомпрессорным утилизатором (ТКУ) и регенерацией теплоты как более экономичные и обладающие удельной мощностью в 1,3…1,5 раза большей, чем в ЗГТУ с Р. Определены характеристики ЗГТУ на переменных режимах, так как подводная техника используется при исследовательских, технологических и транспортных работах при частичных нагрузках и различных видах нагружения. Для улучшения экономичности ЗГТУ на режимах частичного нагружения предложено применить регулируемый сопловой аппарат (РСА) в свободной силовой турбине. На частичных нагрузках посредством РСА можно перераспределить теплоперепад между турбинами, изменить расход газа через турбины, приблизить регулирование к количественному типу. При этом наблюдается увеличение эффективного КПД относительно других способов регулирования при уменьшении мощности двигателя и рост начальной температуры газа, который приближает параметры рабочего цикла двигателя к номинальным значениям. Underwater equipment is especially needed when operating and supplying objects by submarines on the Arctic shelf along the Northern Sea Route associated with ice fields overcoming. Among the various types of power plants for underwater equipment, closed gas turbine plants (CGTP) are promising, capable of operating in a single-circuit version on hydrocarbon types of fuel. Air can be used as an oxidizing agent, which can be stored compressed on ships. In this case, there is no need for a special coastal infrastructure that limits the range of navigation of underwater equipment. A gas turbine engine (GTE) with heat regeneration (R) is adopted as the basis for the basic scheme of CGTP, as it is more economical in comparison with a simple cycle GTE, and the schemes of which are typical for microgas turbine engines. Also considered are CGTP with a turbocompressor utilizer (TCU) and heat regeneration as more economical and having a specific power 1.3...1.5 times higher than in CGTP with R. The characteristics of CGTP in variable modes are determined, since underwater equipment is used in research, technological and transport works at partial modes and various types of loading. To improve the efficiency of CGTP in partial loading modes, it is proposed to use a variable area nozzle (VAN) in a free power turbine. At partial loads, by means of VAN, it is possible to redistribute the heat drop between the turbines, change the gas flow rate through the turbines, and bring the regulation closer to the quantitative type. At the same time, there is an increase in the effective efficiency relative to other control methods with a decrease in engine power and an increase in the initial gas temperature, which brings the parameters of the engine operating cycle closer to the nominal values.

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