Advanced Gas Turbine Research Articles

Exergy assessment and energy integration of advanced gas turbine cycles on an offshore petroleum production platform

On offshore platform applications, power and heat are normally supplied by simple open cycle gas turbine (OCGT) and heat recovery steam generators (HRSG) at lower efficiencies if compared to onshore combined cycle systems. Certainly, due to the reduced available space and the weight constraints, combined cycles are not commonly considered as cogeneration systems on conventional offshore petroleum platforms. However, more stringent environmental policies for the natural gas and oil production activities have motivated the integration assessment of advanced technological solutions that aim to mitigate the environmental impact that conventional offshore platforms are responsible for. Accordingly, in this paper, the effect of the integration of a low emission, oxyfuel gas turbine cycle is analyzed and compared against an amines-based post-combustion system and a conventional offshore petroleum platform operation in terms of its exergy efficiency and reduced atmospheric CO2 emissions. Indeed, although the conventional configuration is the most efficient, the oxyfuel powered platform configuration presents close power cycle efficiency of 27.10% and the lowest specific CO2 emissions of 0.014 kgCO2/toil, whereas the amines-based layout provides the best cogeneration efficiency (55.34%) of the advanced configurations. Moreover, an energy integration analysis is performed to identify the heat recovery potential, while the exergy method is used to evaluate and quantify the most critical components that lead to the largest irreversibilities along the primary separation, cogeneration and gas compression systems. As a result, the study points to ways of decarbonizing offshore applications in the oil and gas sector.

Potentials for Pressure Gain Combustion in Advanced Gas Turbine Cycles

Pressure gain combustion evokes great interest as it promises to increase significantly gas turbine efficiency and reduce emissions. This also applies to advanced thermodynamic cycles with heat exchangers for intercooling and recuperation. These cycles are superior to the classic Brayton cycle and deliver higher specific work and/or thermal efficiency. The combination of this revolutionary type of combustion in an intercooled or recuperated gas turbine cycle can, however, lead to even higher efficiency or specific work. The research of these potentials is the topic of the presented paper. For that purpose, different gas turbine setups for intercooling, recuperation, and combined intercooling and recuperation are modeled in a gas turbine performance code. A secondary air system for turbine cooling is incorporated, as well as a blade temperature evaluation. The pressure gain combustion is represented by analytical-algebraic and empirical models from the literature. Key gas turbine specifications are then subject to a comprehensive optimization study, in order to identify the design with the highest thermal efficiency. The results indicate that the combination of intercooling and pressure gain combustion creates synergies. The thermal efficiency is increased by 10 percentage points compared to a conventional gas turbine with isobaric combustion.

Investigation on a Novel Type of Tubular Flame Burner with Multi-stage Partially-Premixing Features for Liquid-Fueled Gas Turbine

ABSTRACT A new combustion system, which consists of an evaporator and a tubular flame burner with multi-stage inlets, has been developed to meet the growing concerns over the fuel flexibility and flame stability of gas turbines. In the evaporator, a flash-boiling atomization technology was adopted to enhance atomization, evaporation, and fuel-air mixing to provide the burner with the optimized fuel-rich mixture under various operating conditions with liquid fuels. In the new-type of tubular flame burner, a tangential multi-stage inlet structures were proposed to realize fast fuel/air mixing and thus clear combustion with features of excellent stability, uniform temperature profile, and non-flashback. As a practice, ethanol was selected as the liquid fuel to examine the performances of the evaporator and the multi-stage tubular flame burner. Results show that ethanol spray has been fully evaporated under a wide load range owing to the flash-boiling technology, and tubular flames can be established stably and without flashback, and specifically in a wide range of equivalence ratio from 0.23 to 4.6, which has been greatly expanded compared to those of the conventional tubular flame burners. The temperature near the burner outlet were found uniformly distributed in the radial direction across the burner central area, but became very low when approaching the burner cylinder wall, which is believed helpful for decreasing the heat loss to the burner liner and thus preventing it from ablation. These results imply that this new burner has great potentials in application to the advanced gas turbine.

Application of Gaussian process regression models for capturing the evolution of microstructure statistics in aging of nickel-based superalloys

Nickel-based superalloys, used extensively in advanced gas turbine engines, exhibit complex microstructures that evolve during exposure to high temperatures (i.e., aging treatments). In this work, we examine critically if the principal component (PC) representation of rotationally invariant 2-point spatial correlations can adequately capture the salient features of the microstructure evolution in the thermal aging of the superalloys. For this purpose, an experimental study involving microstructure characterization of 27 differently aged (i.e., different combinations of temperature and time of exposure) samples was designed and conducted. Of these, 23 samples were employed for training a Gaussian Process Regression (GPR) model that took the aging temperature and the aging time as inputs, and predicted the microstructure statistics as output. The viability of the approach described above was evaluated critically by comparing the predictions for the four samples that were not used in the training of the GPR model. Furthermore, a new strategy was developed and implemented to generate digital microstructures corresponding to the predicted microstructure statistics. The predicted microstructures were found to be in good agreement with the experimentally measured one, validating the novel framework presented in this work.

Work and efficiency optimization of advanced gas turbine cycles

The paper presents a theoretical analysis of advanced gas-turbine cycles. Specifically, three cycles are investigated, that is the intercooled, the reheat, and the intercooled and reheat cycles. The internal irreversibilities, which characterise the compression and expansion processes, are taken into account through the polytropic efficiencies of the compressors and turbines.New analytical formulations for the overall and intermediate pressure-ratios which maximise the net work of the three aforementioned cycles are proposed along with an order relation between these optimum pressure-ratios. Moreover, the thermal efficiency of these cycles is also analysed providing, among other findings, the ranges of the intermediate pressure-ratios returning a benefit in the thermal efficiency in comparison with the simple cycle. Finally, for the sole intercooled and reheat cycle, a novel analytical expression for the maximum point of the thermal efficiency is given. It is also shown that, for the intercooled and reheat cycle, there is a unique value of the overall pressure-ratio which simultaneously maximises the net work and the thermal efficiency.To give some quantitative information, consider a maximum to minimum cycle-temperature ratio equal to 1573/300 and a compressor (resp. turbine) polytropic-efficiency equal to 0.8 (resp. 0.88). The net work and the thermal efficiency are maximised by a set of overall pressure-ratios obeying an order relation. The simple, the reheat, the intercooled, and the intercooled and reheat cycles reach the maximum net-work (resp. thermal efficiency) for increasing values of the overall pressure-ratio, that is 8.550 (resp. 18.260), 14.950 (resp. 25.039), 20.846 (resp. 39.984), and 73.109 (resp. 73.109). The reheat cycle achieves a 34.899% (resp. 6.077%) gain in the net work (resp. thermal efficiency), while the intercooled cycle returns a 31.477% (resp. 15.970%) increment. The maximum net-work of the intercooled and reheat cycle exactly doubles that of the simple cycle. Finally, the maximum thermal efficiency of the intercooled and reheat cycle yields a 24.966% improvement in comparison with the simple one.

The Combined Effect of Creep and TGO Growth on the Cracking Driving Force in a Plasma-Sprayed Thermal Barrier System

A comprehensive understanding of the failure mechanisms of plasma-sprayed thermal barrier coatings (TBCs) under temperature cycling is a prerequisite for developing the next advanced gas turbine with prolonged thermal cyclic lifetime. In this study, a finite element model including the dynamic growth of thermally grown oxide (TGO) is proposed to explore the combined effect of creep and TGO growth on the cracking driving force in TBCs. A different group of material configurations is designed to satisfy the objective. An adapted interface element based on the virtual crack closure technique is proposed to obtain the strain energy release rate, namely cracking driving force, and crack growth is assessed using a mixed-mode criterion. The results reveal that the cracking predicted by the simulation is in line with the experiment results. Two possible mechanisms of crack coalescence are proposed. The increase in TGO lateral growth strain will induce premature coating spallation. The bond coat and TGO creep only have a slight impact on the ceramic cracking if a comparatively low TGO growth stress is included. Hence, coating optimization suggested in this study may provide additional options for the development of TBCs with extended thermal cyclic lifetime.

ПАРАМЕТРИЧЕСКИЙ АНАЛИЗ СХЕМЫ ПАРОГАЗОВОЙ УСТАНОВКИ С КОМБИНАЦИЕЙ ТРЕХ ЦИКЛОВ ДЛЯ ПОВЫШЕНИЯ КПД ПРИ РАБОТЕ В СЕВЕРНЫХ ГАЗОДОБЫВАЮЩИХ РАЙОНАХ

Актуальность. Парогазовые установки рассматриваются как одно из перспективных направлений развития теплоэнергетических установок, работающих на природном газе. Интерес к их внедрению в России объясняется большими запасами природного газа, низкими капиталовложениями и минимальными выбросами вредных веществ в окружающую среду. Из термодинамики известно, что для достижения высокого КПД цикла необходимо иметь высокую температуру подвода теплоты и низкую температуру ее отвода, а также обеспечить работу оборудования с минимальными внутренними потерями и иметь рациональную тепловую схему взаимосвязи оборудования в цикле. На современном этапе максимальная температура подвода теплоты в камере сгорания газотурбинной установки при существующих конструкционных материалах и способах охлаждения элементов турбины достигла 1600 °С, а температура отвода теплоты в конденсаторе при работе цикла Ренкина на воде по условиям экономичности не может быть ниже 15 °С. При этих условиях на наиболее совершенных трехконтурных парогазовых установках с промежуточным перегревом пара достигнут электрический КПД 63 %. Для цикла Ренкина при работе на воде температура конденсации пара по условию замерзания должна быть выше 0 °С. Для парогазовой установки при работе в условиях низких среднегодовых температур окружающей среды, что характерно для России и особенно отдаленных северных районов добычи газа, можно отводить теплоту в цикле Ренкина значительно ниже 0 °С, но это надежно можно выполнить только применяя конденсаторы с воздушным охлаждением, если в качестве рабочего тела в цикле Ренкина использовать органическое рабочее тело. Недостатком современных органических рабочих тел является низкая предельная температура их термического разложения, которая составляет 300…400 °С. Объект: парогазовые установки с циклами на трех рабочих телах, где верхний цикл Брайтона работает на продуктах сгорания природного газа, средний – цикл Ренкина – работает на воде и водяном паре в интервале температур 100…650 °С, а нижний – Органический цикл Ренкина – работает на органических рабочих телах в интервале температур –30…250 °С. Цель: выбор рациональной технологической схемы парогазовой установки c применением циклов на трех рабочих телах и воздушного конденсатора для возможности надежного отвода теплоты от органического рабочего тела при температуре ниже 0 °С и определение оптимальных параметров циклов. Методы. Сложные теплоэнергетические системы, включая парогазовые установки, характеризуются многообразием процессов, протекающих в их элементах. Такие установки можно эффективно исследовать только с помощью методов математического моделирования и оптимизации. При проведении исследований в данной работе использован системный подход, методы энергетических балансов и расчет термодинамических и теплофизических параметров рабочих тел с помощью современных сертифицированных программ. Результаты. Разработана оригинальная схема парогазовой установки утилизационного типа с циклами на трех рабочих телах, где верхний цикл Брайтона работает на продуктах сгорания природного газа, средний цикл Ренкина работает на воде и водяном паре, нижний – Органический цикл Ренкина – работает на органическом рабочем теле с конденсацией его в воздушном конденсаторе. Разработана математическая модель и программа расчета предложенной схемы. Определено наиболее эффективное органическое рабочее тело для нижнего цикла Ренкина. Проведен параметрический анализ влияния основных параметров циклов на КПД брутто и нетто парогазовой установки.

A constitutive model for the sintering of suspension plasma‐sprayed thermal barrier coating with vertical cracks

AbstractThe degradation of mechanical properties due to sintering is one of the major issues during high temperature service of thermal barrier coating system for advanced gas turbines. In this study, a constitutive model was developed by the variational principle, based on the experimentally observed microstructure features of suspension plasma‐sprayed thermal barrier coatings. The constitutive model was further implemented in finite element analysis software, in order to investigate the effect of vertical cracks. The evolution of microstructure during sintering, coating shrinkage and mechanical degradation were predicted. The numerical predictions of Young's modulus were generally in agreement with experimental results. Furthermore, the effect of vertical cracks on the strain tolerance and sintering resistance were discussed. It was confirmed that the introduction of vertical cracks contributed to the improvement of both properties.

Dynamic analysis of operating flexibility of the advanced humid air gas turbine (AHAT) system

Dynamic analysis of operating flexibility of the advanced humid air gas turbine (AHAT) system

Numerical investigation of advanced gas turbine combined cycle coupled with high-temperature nuclear reactor and cogeneration unit

In the European Union by 2050, more than 80% of electricity should be generated using nongreenhousegases energy technology. Nuclear power systems share at present about 15% of the power market and thistechnology can be the backbone of a carbon-free European power system. Energy market transitions are similar to global pathways were analysed in the Intergovernmental Panel on Climate Change report. From a practical point of view currently, the most advanced and most effective technology for electricity generation is based on a gas turbine combined cycle. This technology in a normal way uses natural gas, synthesis gas from the coal gasification or crude oil processing products as the energy carriers but at the same time, such system emits sulphur oxides, nitrogen oxides, and CO2 to the environment. In thepresent paper, a thermodynamic analysis of environmentally friendly power plant with a high–temperature gas nuclear reactor and advanced configuration of gas turbine combined cycle technology is investigated. The presented analysis shows that it is possible to obtain for proposed thermalcycles an efficiency higher than 50% which is not only more than could be offered by traditional coal power plant but much more than can be proposed by any other nuclear technology.

Thermodynamic analysis of high temperature nuclear reactor coupled with advanced gas turbine combined cycle

One of the most advanced and most effective technology for electricity generation nowadays based on a gas turbine combined cycle. This technology uses natural gas, synthesis gas from the coal gasification or crude oil processing products as the energy carriers but at the same time, gas turbine combined cycle emits SO2, NOx, and CO2 to the environment. In this paper, a thermodynamic analysis of environmentally friendly, high temperature gas nuclear reactor system coupled with gas turbine combined cycle technology has been investigated. The analysed system is one of the most advanced concepts and allows us to produce electricity with the higher thermal efficiency than could be offered by any currently existing nuclear power plant technology. The results show that it is possible to achieve thermal efficiency higher than 50% what is not only more than could be produced by any modern nuclear plant but it is also more than could be offered by traditional (coal or lignite) power plant.

Theoretical assessment of integration of CCS in the Mexican electrical sector

This research evaluates the current most advanced and proven Gas Turbine (GT) technologies in a 1 × 1 scheme (400 MW on average) for their application in CO2 capture schemes. It has been demonstrated that the minimum energy required for the separation of CO2 is higher in a Natural Gas Combined Cycle (NGCC) than in a coal-fired power plant. Therefore, existing schemes were evaluated to assess the increased CO2 content in the Exhaust Gases (EG) for a NGCC in order to help reduce the energy penalty and the investment cost in CO2 capture systems. The schemes analyzed were: Exhaust Gas Recirculation (EGR), Evaporative Gas Turbine (EvGT), Supplementary Firing Combustion (SFC), External Firing combustion (EFC) and alternating systems with Selective Exhaust Gas Recycle (S-EGR) and hybridization. The most common GTs used in Mexico: Mitsubishi (15%), Siemens (41%) and General Electric (GE) (44%) including M − 501 GAC, SGT6-8000H and GE7HA.01 models were evaluated in Thermoflex 26®. For these, Levelized Costs of Electricity (LCOE) of 31.46, 31.18 and 31.05 USD/MWh, respectively, were obtained. GE offers the lowest LCOE and the EGR system presented the lowest energy penalty when the CO2 capture system was modeled in HYSYS V8.6®. Implementation of EGR helped to improve the energy efficiency of the NGCC and increased the content of CO2 from 4.2 to 7.1 mol% at 40%EGR. Similarly, EGR helped to reduce the LCOE in the integrated system with CO2 Capture by 10 USD/MWh.

Study of Sequential Two-Stage Combustion in a Low-Emission Gas Turbine Combustion Chamber

In this paper, we analyzed advanced ground-based power gas turbine units with low-emission combustion chambers used for consecutive two-stage fuel combustion. Such low-emission combustion chambers have a wide range of stable performance modes with reduced emission of harmful substances. The two-stage combustion chambers used in gas turbine units of various capacities—small (for example, M7A-03 with a capacity of approximately 8–10 MW), medium (L20A and L30A with a capacity of 18–30 MW) and large (9HA and GT36 with a capacity of over 300 MW)—showed their universality, efficiency, and good possibilities for scaling. The designs of low-emission combustion chambers for gas turbine units of different capacities are fundamentally similar. They consist of two sequentially located combustion volumes (stages), and each of them has its own burner unit. The first burner unit is typical for low-emission combustion chambers with the combustion of the premixed air-fuel mixture and consists of swirlers, mixing zone, fuel injectors, and igniters. The second burner unit is located downstream, and air-fuel mixtures of a different composition are supplied into it through special holes. The combustion of the mixtures occurs at a lower oxygen content and higher temperature. The ignition, work until idling, and loading before switching to the low-emission mode and switching to it are performed by the operation regulation of the first burner unit. Fuel in the second burner unit is supplied when a certain temperature of the gases arriving from the first combustion stage is achieved, which ensures its self-ignition. The further load is regulated by the fuel supply to the second burner unit. The design implementation of the sequential two-stage combustion scheme and approaches to regulating fuel and air distribution over the stages that ensures stable nonpulsating combustion are different and so they are of great scientific and practical interest.

Advanced gas turbine performance modelling using response surface methods

ABSTRACTSurrogate models are widely used for dataset correlation. A popular application very frequently shown in public literature is in the field of engineering design where a large number of design parameters are correlated with performance indices of a complex system based on existing numerical or experimental information. Such an approach allows the identification of the key design parameters and their impact on the system’s performance. The generated surrogate model can become part of wider computational platforms and enable optimisation of the complex system without the need to run expensive simulations.In this paper, a number of design point simulations for a combined gas-steam cycle are used to generate a response surface. The generated response surface correlates a range of cycle’s key design parameters with its thermal efficiency while it also enables identification of the optimum overall pressure ratio and the high pressure level of the raised steam across a range of recuperator effectiveness, pinch temperature difference across the heat recovery steam generator and the pressure at the condenser. The accuracy of a range of surrogate models to capture the design space is evaluated using root mean square statistical metrics.

Morphological evolution and failure of LZC/YSZ DCL TBCs by electron beam-physical vapor deposition

Low thermal conductivity thermal barrier coatings (TBCs) with double ceramic layers (DCL) structure are receiving tremendous attention for promising application in advanced gas turbine engine. It still remains a big challenge for the investigation of morphological evolution of TGO and failure model in new DCL coatings. Here we describe La2O3-ZrO2CeO2 (LZC)/YSZ DCL TBCs prepared by electron beam-physical vapor deposition (EB-PVD). A composite of pyrochlore and fluorite is formed in LZC/YSZ coating. The microstructure of LZC/YSZ coating is composited of feathery nanostructure and intra-columnar pores. The LZC/YSZ DCL coating shows relativity low thermal conductivity and high thermal cycling lifetime. The growth behavior of TGO layer in LZC/YSZ coating is investigated in detail showing two distinct features (parabolic growth kinetics and straight growth kinetics). The evolution of residual stress has been experimentally measured and discussed by Raman spectroscopy. Based on the experimental data, the growth behavior of TGO layer, the evolution of residual stress and the element outward diffusion would be the primary factors for the failure of LZC/YSZ DCL TBCs.

Gas Turbine Fouling: A Comparison Among 100 Heavy-Duty Frames

Over recent decades, the variability and high costs of the traditional gas turbine fuels (e.g., natural gas) have pushed operators to consider low-grade fuels for running heavy-duty frames. Synfuels, obtained from coal, petroleum, or biomass gasification, could represent valid alternatives in this sense. Although these alternatives match the reduction of costs and, in the case of biomass sources, would potentially provide a CO2 emission benefit (reduction of the CO2 capture and sequestration costs), these low-grade fuels have a higher content of contaminants. Synfuels are filtered before the combustor stage, but the contaminants are not removed completely. This fact leads to a considerable amount of deposition on the nozzle vanes due to the high temperature value. In addition to this, the continuous demand for increasing gas turbine efficiency determines a higher combustor outlet temperature. Current advanced gas turbine engines operate at a turbine inlet temperature (TIT) of (1400–1500) °C, which is high enough to melt a high proportion of the contaminants introduced by low-grade fuels. Particle deposition can increase surface roughness, modify the airfoil shape, and clog the coolant passages. At the same time, land-based power units experience compressor fouling, due to the air contaminants able to pass through the filtration barriers. Hot sections and compressor fouling work together to determine performance degradation. This paper proposes an analysis of the contaminant deposition on hot gas turbine sections based on machine nameplate data. Hot section and compressor fouling are estimated using a fouling susceptibility criterion. The combination of gas turbine net power, efficiency, and TIT with different types of synfuel contaminants highlights how each gas turbine is subjected to particle deposition. The simulation of particle deposition on 100 gas turbines ranging from 1.2 MW to 420 MW was conducted following the fouling susceptibility criterion. Using a simplified particle deposition calculation based on TIT and contaminant viscosity estimation, the analysis shows how the correlation between type of contaminant and gas turbine performance plays a key role. The results allow the choice of the best heavy-duty frame as a function of the fuel. Low-efficiency frames (characterized by lower values of TIT) show the best compromise in order to reduce the effects of particle deposition in the presence of high-temperature melting contaminants. A high-efficiency frame is suitable when the contaminants are characterized by a low-melting point thanks to their lower fuel consumption.

Surge prevention for gas turbines connected with large volume size: Experimental demonstration with a microturbine

The aim of this work is the demonstration of a surge prevention technique for advanced gas turbine cycles. There is significant surge risk in dynamic operation for turbines connected with large volume size additional components, such as a fuel cell stack, a saturator, a solar receiver or a heat exchanger for external combustion. In comparison with standard gas turbines, the volume size generates different behaviour during dynamic operations (with significant surge risk), especially considering that such additional components are including important dynamic constraints.In order to prevent the surge events, a vibration analysis was carried out to develop precursors which are able to highlight the approach of this unstable operative zone. Since the sub-synchronous content of the measured vibrations is significantly increasing approaching the surge line, special attention was devoted to this parameter.The demonstration of a surge prevention system based on the sub-synchronous vibration content was carried out at the Innovative Energy Systems Laboratory of the University of Genoa. In this laboratory, a recuperated microturbine connected with a large size vessel was used. Starting from the stable operation, closing a valve in the main air line or increasing the compressor inlet temperature produced operative conditions with significant surge risk. The increase in sub-synchronous vibration content detected by the control system was used to perform an active operation (bleed valve opening) to avoid the approaching surge event.

The methodology for determining of the energy costs for the probabilistic nature of the load of a machine-tractor unit

The random nature of the load is the main cause of deterioration of energy parameters and technical and economic indicators of machine-tractor units (MTU). Oscillations of the load lead to an increase in energy costs for technological processes. Direct fuel and energy costs should be determined and predicted with a high degree of reliability, taking into account the specifics of the work of the MTU and the dynamics of its performance of technological processes. The identification and optimization of energy costs of the MTU will ensure an increase in the efficiency of the technological processes and technologies of cultivation in crop production. The subject of the study is the development of mathematical models for determining and optimizing the direct energy costs of MTU equipped with advanced gas turbine engine (GTE) engines. The purpose of the research is to develop a methodology for determining the direct fuel and energy costs of MTU, taking into account the probabilistic nature of the load. The novelty of the research consists in the developed mathematical models and calculation algorithm, as well as optimization of the direct fuel and energy costs of MTU with GTE. The proposed methodology is developed on the basis of a systematic approach, generalization, and analysis of experimental data, mathematical modeling of processes. Experimental studies were carried out in laboratory facilities and in the field using modern measuring instruments and recording experimental data. The proposed methodology allows, with a probability of 0,90-0,95, to predict the optimal values of the direct fuel and energy costs of the MTU with GTE. As an example, the article gives examples of calculation and optimization of direct fuel and energy costs of plowing unit consisting of a Kirovets tractor with a GTD-350T gas turbine engine and a PNI-8/9-40 plow at various levels of turbocharger speed. It is established that at the 100 % level of the turbo compressor speed and the variation of the load variation coefficient from 0 to 0,333, the optimal values of the direct fuel and energy costs of the plowing unit increase from 543,0 to 723,12 MJ/ha. The same trend of increasing the direct fuel and energy costs of MTU is also observed in other levels of implementation of the turbo GTE turbocharger speed. It should be noted that with a decrease in the level of implementation of the turbocharger GTE's speed, direct fuel, and energy costs are increasing. The proposed methodology allows to determine and optimize the values of direct fuel and energy costs of MTU with GTE taking into account the probabilistic nature of the load under the specific conditions of their operation.

Advanced Cooling in Gas Turbines 2016 Max Jakob Memorial Award Paper

Gas turbines have been extensively used for aircraft engine propulsion, land-based power generation, and industrial applications. Power output and thermal efficiency of gas turbines increase with increasing turbine rotor inlet temperatures (RIT). Currently, advanced gas turbines operate at turbine RIT around 1700 °C far higher than the yielding point of the blade material temperature about 1200 °C. Therefore, turbine rotor blades need to be cooled by 3–5% of high-pressure compressor air around 700 °C. To design an efficient turbine blade cooling system, it is critical to have a thorough understanding of gas turbine heat transfer characteristics within complex three-dimensional (3D) unsteady high-turbulence flow conditions. Moreover, recent research trend focuses on aircraft gas turbines that operate at even higher RIT up to 2000 °C with a limited amount of cooling air, and land-based power generation gas turbines (including 300–400 MW combined cycles with 60% efficiency) burn alternative syngas fuels with higher heat load to turbine components. It is important to understand gas turbine heat transfer problems with efficient cooling strategies under new harsh working environments. Advanced cooling technology and durable thermal barrier coatings (TBCs) play most critical roles for development of new-generation high-efficiency gas turbines with near-zero emissions for safe and long-life operation. This paper reviews basic gas turbine heat transfer issues with advanced cooling technologies and documents important relevant papers for future research references.

Advanced gas turbines health monitoring systems

Advanced gas turbines health monitoring systems