Modeling and numerical analysis of the effect of blade roughness on particle deposition in a flue gas turbine

The increasing amount of renewable energy and emission norms challenge gas turbine power plants to operate at part-load with high efficiency, while reducing NOx and CO emissions. A novel solution to this dilemma is external Flue Gas Recirculation (FGR), in which flue gases are recirculated to the gas turbine inlet, increasing compressor inlet temperature and enabling higher part load efficiencies. FGR also alters the oxidizer composition, potentially leading to reduced NOx levels. This paper presents a kinetic model using chemical reactor networks in a lean premixed combustor to study the impact of FGR on emissions. The flame zone is split in two perfectly stirred reactors modelling the flame front and the recirculation zone. The flame reactor is determined based on a chemical time scale approach, accounting for different reaction kinetics due to FGR oxidizers. The recirculation zone is determined through empirical correlations. It is followed by a plug flow reactor. This method requires less details of the flow field, has been validated with literature data and is generally applicable for modelling premixed flames. Results show that due to less O2 concentration, NOx formation is inhibited down to 10–40% and CO levels are escalated up to 50%, for identical flame temperatures. Increasing combustor pressure leads to a rise in NOx due to thermal effects beyond 1800 K, and a drop in CO levels, due to the reduced chemical dissociation of CO2. Wet FGR reduces NOx by 5–10% and increases CO by 10–20%.

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Thermo-Economic Assessment Under Electrical Market Uncertainties of a Combined Cycle Gas Turbine Integrated With a Flue Gas-Condensing Heat Pump

10.1115/1.0002989v ◽

2021 ◽

Author(s):

Alberto Vannoni ◽

Andrea Giugno ◽

Alessandro Sorce

Keyword(s):

Gas Turbine ◽

Heat Pump ◽

Flue Gas ◽

Economic Assessment ◽

Combined Cycle ◽

Market Uncertainties

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Uncertainty Analysis of Inflow Conditions on an HPT Gas Turbine Nozzle: Effect on Particle Deposition

Volume 2B: Turbomachinery ◽

10.1115/gt2020-15370 ◽

2020 ◽

Author(s):

R. Friso ◽

N. Casari ◽

M. Pinelli ◽

A. Suman ◽

F. Montomoli

Keyword(s):

Gas Turbine ◽

Energy Efficient ◽

Gas Turbines ◽

Particle Deposition ◽

Operating Conditions ◽

Wide Range ◽

And Performance ◽

Gas Turbine Nozzle ◽

The Impact ◽

Inflow Conditions

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.

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Colour changing material for the estimation of flue gas radiation on the miniature gas turbine surface

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/14644207211045520 ◽

2021 ◽

pp. 146442072110455

Author(s):

Mahalingam Arulprakasajothi ◽

Pegyyem Lokaiah Rupesh ◽

Hitesh Kumar Rana ◽

Kariappan Elangovan

Keyword(s):

Fluid Dynamics ◽

Temperature Gradient ◽

Surface Temperature ◽

Gas Turbine ◽

Turbine Blade ◽

Flue Gas ◽

Dynamics Simulation ◽

Blade Surface ◽

Numerical Validation ◽

Surface Temperature Gradient

The gas turbine is being used in the applications of the aircraft propulsion system and land-based power generating systems more effectively. The manufacturers should optimise the temperature of the gas turbine engine components to enhance the life span of the components. The present research work concentrates on determining the surface temperature gradient on the fabricated turbine blades using a colour changing paint based on temperature attained on the surface. A calibration database has been created, and the surface temperature has been detected based on the available colour contours on the blade surface using human vision. An image processing algorithm has also been proposed for accurate temperature measurement on the blade surface. The obtained surface temperature using colour changing paint multi-colour change 350-8 has been calibrated with the conventional measurement technique IR thermography for experimental validation. A computational fluid dynamics simulation model of the turbine blade has been simulated to predict the surface temperature of blades using analysis systems fluid dynamics for numerical validation. The experimental and numerical validation results have shown a nominal value of error, which proves that the surface temperature gradient can be easily predicted with the help of temperature indicating paint using the proposed algorithm. The study has been extended further to evaluate the amount of emissive power radiated by the flue gas on the turbine blade surface based on the temperature and the wavelength of the colour obtained for the health monitoring of the blade.

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Thermo-Economic Assessment Under Electrical Market Uncertainties of a Combined Cycle Gas Turbine Integrated With a Flue Gas-Condensing Heat Pump

Volume 5: Controls, Diagnostics, and Instrumentation; Cycle Innovations; Cycle Innovations: Energy Storage ◽

10.1115/gt2020-15400 ◽

2020 ◽

Author(s):

Alberto Vannoni ◽

Andrea Giugno ◽

Alessandro Sorce

Keyword(s):

Power Plant ◽

Power Systems ◽

Gas Turbine ◽

Heat Pump ◽

Flue Gas ◽

Power Plants ◽

Greenhouse Gas Emission ◽

Capital Expenditure ◽

Combined Cycle ◽

Gas Turbine Power Plant

Abstract Renewable energy penetration is growing, due to the target of greenhouse-gas-emission reduction, even though fossil fuel-based technologies are still necessary in the current energy market scenario to provide reliable back-up power to stabilize the grid. Nevertheless, currently, an investment in such a kind of power plant might not be profitable enough, since some energy policies have led to a general decrease of both the average price of electricity and its variability; moreover, in several countries negative prices are reached on some sunny or windy days. Within this context, Combined Heat and Power systems appear not just as a fuel-efficient way to fulfill local thermal demand, but also as a sustainable way to maintain installed capacity able to support electricity grid reliability. Innovative solutions to increase both the efficiency and flexibility of those power plants, as well as careful evaluations of the economic context, are essential to ensure the sustainability of the economic investment in a fast-paced changing energy field. This study aims to evaluate the economic viability and environmental impact of an integrated solution of a cogenerative combined cycle gas turbine power plant with a flue gas condensing heat pump. Considering capital expenditure, heat demand, electricity price and its fluctuations during the whole system life, the sustainability of the investment is evaluated taking into account the uncertainties of economic scenarios and benchmarked against the integration of a cogenerative combined cycle gas turbine power plant with a Heat-Only Boiler.

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