Keywords: Others
Abstract: The power sector’s journey to decarbonize, often referred to as the Energy Transition, is characterized by rapid deployment of renewable energy resources and a rapid reduction in coal, the most carbon-intensive power generation source. Based on our extensive analysis and experience across the breadth of the global power industry, GE Vernova believes that the accelerated and strategic deployment of renewables and gas power can change the near-term trajectory for climate change, enabling substantive reductions in emissions quickly, while in parallel continuing to advance the technologies for near zero carbon power generation. Part of this deployment of gas power may involve the use of hydrogen as a fuel in order to reduce CO2 emissions.

There are two ways to systematically approach the task of turning high efficiency gas generation into a zero or near zero carbon resource: pre and post-combustion. Pre-combustion refers to the systems and processes upstream of the gas turbine and post-combustion refers to systems and processes downstream of the gas turbine. The most common approach today to tackle pre-combustion decarbonization is simple: to change the fuel, and the most talked about fuel(s) for decarbonization of the power sector is hydrogen and ammonia. GE Vernova is a world leader in gas turbine fuel flexibility, including more than 100 gas turbines that have (or continue to) operate on fuels that contain hydrogen. This fleet has accumulated more than 8 million operating hours and produced more than 530 Terawatt-hours of electricity. It includes a group of more than 30 gas turbines that have operated on fuels with at least 50% (by volume) hydrogen. These units have accumulated more than 2.5 million operating hours, giving GE a unique perspective on the challenges of using hydrogen as a gas turbine fuel.

For post-combustion decarbonization, there is a tool chest of different technologies that can remove CO2 from the flue gases with the most common being in a process referred to as carbon capture. The general concept of carbon capture involves introducing a specialized chemical which has an affinity to carbon into the plant exhaust stack. Once the CO2 and the chemical bond, the compound is taken to a separate vessel and separated into its constituents. The resulting pure CO2 is taken to a compression tank and is ready for transportation. This CO2 is then transported to either a geologic formation deep underground for permanent storage, or re-used in industrial processes, thus completing the process of Carbon Capture and Utilization or Sequestration (CCUS).

It’s important to note that pre and post combustion decarbonization approaches can be employed on existing installed gas turbines as a retrofit or included in the design of a new power plant, avoiding the potential “lock-in” of CO2 emissions for the entire life of the power plant.

Keywords: Combustion Instability
Abstract: This paper aims to confirm the effect of the pilot flame on the combustion instability damping in terms of thermo-acoustic analysis. To analyze the damping effect of the pilot flame, 1D thermo-acoustic model was developed by a closed-loop system for multi-input multi-output. This model can consider two flame transfer functions, so it can acoustically analyze the effect of the pilot flame. Through this model, the influence of the pilot flame transfer function and combustion instability characteristics depending on the parameter changes of main and pilot flame transfer functions were studied by introducing Crocco’s n-τ model.

Keywords: Combustion Instability
Abstract: This researh propose a Network model using Network modeling techinques for calculating the resonance frequency of geometry as a technique for solving the combustion instability of an annular gas turbine combustor (GT24). The model is developed based on the law of conservation of mass, momentum, and energy between network elements according to area changes. The acoustic field analysis of the complex geometry actual annular gas turbine combustor (GT24) was analyzed using the current model. Furthermore, for the reliability of the analytical results of the network modeling technique, the results were compared using Helmholtz solvers based on the 3D element method (FEM).

Keywords: Combustion Instability, Others (Industrial Gas Turbine and Power Systems)
Abstract: The combustion instabilities of the high-frequency transverse mode are of necessity to be accurately predicted and well controlled in the can combustor. In this work, an analytical model containing multiple nozzles and complicated outlet boundary conditions is established with the benefit of the multi-source integration using three-dimensional Green’s function. To quantitatively characterize the complicated outlet boundary conditions therein, the generalized modal reflection coefficients are taken into account. Results show that when the outlet of the combustion chamber is considered as a hard wall, combustion instability of the first-order radial mode is least likely to be excited in the case of the radial positions of the nozzles at the pressure node. Meanwhile, the stability behaviors will be modulated with the consideration of different types of flame responses. However, the stability behaviors of the first-order radial mode show a completely different scenario under the condition of complicated outlet boundary conditions in comparison with the hard wall for outlet. This model is used to reveal the involved physical insight enabling the optimal design of controlling combustion instabilities in can combustor systems.

Keywords: New Diagnostics Technique, Monitoring Technology, Combustion Instability
Abstract: Presence of combustion instability is so fatal that it must be prevented prior to the circumstance be occurred in a gas turbine operation point of view. This incident occurs with numerous factors and, at the same time, interrupts stable gas turbine operation. Due to the complexity of its mechanism, it is regarded as challenging problem. However, due to the existence of accumulated operation data, there is room for breaking through these difficulties. In this research, diagnostics on abnormal combustion has been conducted with deep learning approach. At first, using variational auto-encoder, time-series dynamic pressure data is modified in 3-dimensional latent variables with its states; stable, transition, and unstable. After that, upon its sequence information, the latent variables get trained using long-short term memory method. The trained models have shown remarkable result to diagnose abnormal combustion.

Keywords: Turbines, Heat Transfer Simulation
Abstract: Impingement cooling is one of the most potential internal cooling techniques for gas turbine blades because of its high heat dissipation, which is usually arranged in the leading-edge or mid-chord zone. Impingement cooling is accompanied by crossflow, and the crossflow is actually coolant being heated, so its temperature is higher than jet coolant. However, there are few studies on the effect of crossflow temperature on impingement cooling, and quantitative research are even more blank. To this end, this paper numerically simulated an array impingement cooling with different temperature initial crossflow by solving steady three-dimensional Reynolds-Averaged Navier-Stokes (RANS) equations. Both the flow field and heat transfer characteristics of impingement cooling with four crossflow-to-jet temperature ratios (TR=1.0, 1.1, 1.2, 1.3) under four different crossflow-to-jet mass flow ratios (CMFR=0.3, 0.5, 0.7, 0.9) and four jet Reynolds numbers (Rej=15,000, 25,000, 35,000, 45,000) are investigated in detail. Results show that (1) with the increase of jet Reynolds number, the Nusselt number increases, but the friction loss coefficient decreases; (2) with the increase of crossflow-to-jet mass flow ratio, both the Nusselt number and friction loss coefficient decreases; (3) with the increase of crossflow-to-jet temperature ratio, the heat transfer of target surface always decreases, but the variation of friction loss coefficient is related to crossflow-to-jet mass flow ratio. To be specific, when the crossflow-to-jet mass flow ratios are 0.3 and 0.5, the friction loss coefficient decreases with the increase of crossflow-to-jet temperature ratio, but when the crossflow-to-jet mass flow ratio are 0.7 and 0.9, the friction loss coefficient increases with the increase of crossflow-to-jet temperature ratio. The research results will clarify the action mechanism of crossflow-to-jet temperature ratio on impingement cooling.

Keywords: Turbines, General Heat Transfer, Film Cooling, Internal Cooling, Computational Fluid Dynamics
Abstract: The turbine of an aeroengine is exposed to a high-temperature mainstream, making a sufficiently dimensioned cooling and sealing for all components involved indispensable. This study focuses on the cavity at the bottom of the rotor platform, which is connected to the main flow through the midpassage gap between two adjacent blades mounted on the turbine disc. A numerical approach has been conducted to obtain the flow mechanism, sealing effectiveness and heat transfer characteristic for various purge flow rates in the bottom platform cavity. The results of the steady-state simulations show small variations in the flow pattern, but significant changes in the thermal load parameters, such as the adiabatic cooling effectiveness or the heat transfer coefficient. The necessity for a balanced thermal safety and overall efficiency demands a better understanding of the aerodynamic and thermal behavior in the analyzed cavity to derive an optimized purge flow configuration.

Keywords: Heat Transfer Measurement, General Heat Transfer, Film Cooling, Internal Cooling, Turbines
Abstract: Internal channel is a vital cooling structure for blade cooling of gas turbine. However, under rotation condition, the heat transfer performance of cooling channel is significantly different from that under stationary state. To study the heat transfer characteristics of internal channel at rotation condition, in the paper, a rotating experiment rig system has been established. Transient crystal liquid is adopted as measurement approach to obtained the surface temperature and Nusselt number. Besides, a ribbed U channel with transparent organic glass was utilized on the rotating experiment bench as standard to verify the accuracy of the bench. The results indicated that the experiment results meet the results of the literature and simulation well under nonrotation and rotation conditions, which verifies the accuracy of the rotating experiment rig for cooling channel.

Keywords: Novel Cooling Technology, General Heat Transfer, Film Cooling, Internal Cooling, Heat Transfer Measurement
Abstract: The narrow cooling passage of the internal section of the turbine blades is one of the complicated zones of the gas turbine system. It confronts a high temperature. Pin-fins are an excellent structure to insert in this section to ensure effective cooling. It accomplishes a higher heat transfer coefficient. Pin-fins are also implemented as a mechanical structure to bridge the thin metallic pressure surface and suction surface. However, the pressure drop is significantly higher in the case of pin-fin cooling, which can lower the thermal performance of the cooling channel. The optimization of pin-fin design is important to find the optimal pressure drop. The present study considers two different pin-fin designs, i.e., partial spherical and dome with different arrays of pin-fins. The experimental and computational investigation was conducted with rotation numbers ranging from Ro=0 to Ro=0.13. The experimental study was conducted with Reynolds (Re) numbers ranging from 9,000 to 50,000. A computational study was conducted with the Large Eddy Simulation (LES) technique. The final judgment was completed based on the cooling channel's heat transfer coefficient, friction factor, and thermal performance. The cooling channel with dome-shaped pin-fins with an array of 14×2 pin-fins showed a better thermal performance than other cooling channels.

Keywords: Computational Fluid Dynamics, Heat Transfer Simulation, General Heat Transfer, Film Cooling, Internal Cooling
Abstract: The thermal load on the endwalls of the hot gas path of gas turbines, in particular those of the nozzle guide vanes (NGV), has increased considerably over the last decades. Therefore, cooling concepts have been the focus of R&D efforts for some time. Dedicated cooling, i.e., film-cooling holes in the most thermally highly-loaded areas, can be applied. This requires both additional cooling air and costly mechanical efforts. When using purge air, neither of these two disadvantages comes into play. For this reason, cooling the endwalls with purge air is very attractive. In order to establish and evaluate this cooling concept, dedicated tests are normally performed. Both the required time and financial resources preclude testing every possible geometry. Hence CFD is used. The thermal load consists of both the film-cooling effectiveness and the heat transfer on the endwall. Combined, these yield the Net Heat Flux Ratio (NFHR). In an industrial environment, RANS solvers are used to carry out CFD-analyses. These have difficulties in modelling shear stresses and turbulence and thus an existing k--SST-model was modified. The model was developed based on film-cooling experiments and validated on experiments of endwall cooling in a linear cascade. In this paper, these experiments, the CFD-model and its validation will be presented and discussed in detail.

Keywords: Turbines, General Heat Transfer, Film Cooling, Internal Cooling, Heat Transfer Simulation
Abstract: The present study proposed a novel crescent-dimpled film hole based the dimpled film hole and the cooling performance and flow structures at two blowing ratios 0.5 and 1.0, were obtained and analyzed by the steady-state RANS method, based on realizable k-epsilon model with enhanced wall treatment. The crescent-dimpled film hole has a crescent-shape dimple exit, which has a diameter 4 times the film hole diameter and a curved profile vertical trailing edge. Compared with conventional cylindrical film hole and dimpled film hole, the crescent-dimpled film hole leads to a significant improvement in adiabatic film cooling effectiveness and the lateral coverage is much wider. The mechanism is that the closer vertical trailing edge enhanced the interaction with the coolant jet, which forms larger high cooling performance area and two coolant branches. As blowing ratio increases to 1.0, the branches and core area becomes larger leads to a higher cooling performance.

Keywords: General Heat Transfer, Film Cooling, Internal Cooling, Computational Fluid Dynamics, Turbines
Abstract: Efficient impingement cooling systems are crucial for turbomachinery applications. This study numerically explores eight different turbulator geometries in generic impingement cooling systems, focusing on the role of these turbulators on both hole and target plates. RANS simulations and the DLR TRACE solver are utilized. On the hole plate a U-shaped turbulator (called ArcConic) uses the cross-flow to reinforce the jet by guiding it into the subsequent jets and thus increasing their effective jet Reynolds number. The target plate turbulators impact flow patterns, turbulence and surface area. Our findings show a moderate pressure drop and an 26% increase in heat flux. This research contributes valuable design insights for developing efficient impingement cooling systems and addresses the practicality of manufacturing these configurations using selective laser melting (SLM) technology.

Keywords: General Heat Transfer, Film Cooling, Internal Cooling, Novel Cooling Technology, Heat Transfer Simulation
Abstract: Transpiration cooling with phase change is a novel active thermal protection method with higher cooling efficiency. The modified two-phase mixture model and the multi-domain coupling computation are adopted to study its transient response. Different fluctuation periods of coolant mass flux and different thermal conductivities of the porous matrix are discussed, respectively. The simulation results show that there are clear delay and accumulation effect in the transient response, and the coolant injection pressure is much more sensitive than the temperature to the coolant mass flux. Moreover, both temperature and injection pressure have their own extreme values during transient response. Then, the instability on the porous matrix surface is closely related to the location of the coolant phase transition. Using the porous matrix with greater thermal conductivity can not only help to reduce the surface temperature of the structure under steady condition, but also has stronger stability under transient condition. The research of this work is of great guidance and practical importance for the extension of the application of transpiration cooling with phase change in the real environment.

Keywords: Axial Compressors
Abstract: The accurate simulation of the tip clearance flow is the premise of flow mechanism analysis and compressor performance optimization. The detached-eddy simulation (DES) method, considering the calculation amount and accuracy has excellent potential in this certain type of flow. However, the inevitable 'gray area' in the DES method is one of the critical hidden dangers that weaken the prediction accuracy of the tip clearance flow. A simplified model considering multi-walls and shear jet characteristics is taken to research the effect of grey areas on the prediction of tip clearance flow. Compared with the large-eddy simulation (LES) result, this paper studies the influence of the 'gray area' on the macroscopic parameters, the leakage vortex trajectory predicted by the DES method is quite different downstream near the outlet of the channel, while the difference in the loss is mainly reflected in the prediction of mixing loss caused by fluctuation.

Keywords: Computational Fluid Dynamics, Axial Compressors, Gas Turbines for Electric Power Generation
Abstract: In recent years, the use of renewable energy sources has become increasingly popular. The amount of power generated fluctuates greatly depending on weather conditions and time of day. Gas turbines are used to respond quickly to these fluctuations in power generation. However, since the operation to respond to the fluctuations in power generation is outside the design point, the internal flow of the gas turbine compressor becomes unstable. As a result, unsteady load fluctuations on the blade can cause serious damage and reduce performance of the compressor. In our previous study, we conducted a 1.5-stage full-annulus unsteady simulation of a compressor in an industrial gas turbine, considering partial-load operation. The result indicated that the frequency of pressure fluctuation closely corresponded with the blade’s natural frequency. However, only some of the various partial load conditions had been clarified in the study. To avoid conditions that may lead to blade failure, it is useful to conduct calculations under a various operating of conditions and the conditions that may result in unstable flow patterns in advance. This paper proposes a method to classify time series big data obtained from flow calculations conducted under 21 different conditions. We examine the Euclidean distance and correlation coefficient as classification metrics. The Euclidean distance is the linear distance between two points. The correlation coefficient is a measure of the strength of the relationship between two types of data. Time series data of pressure loads on the first-stage stator blades were calculated for 21 different cases. Then, the data were converted to frequency data by Fast Fourier Transform (FFT). Finally, the frequency data were classified by Euclidean distance and correlation coefficient. The results showed that the correlation coefficient is effective for binary classification of stable and unstable conditions, while the Euclidean distance can identify differences in instability by using the unstable condition as a reference.

Keywords: Unsteady Flow and Flow Control in Turbine, Turbines, Computational Fluid Dynamics
Abstract: Modern high-performance low-pressure turbines (LPT) usually encounter flow problems at low Reynolds numbers, especially for high-altitude UAVs under cruise conditions. Flow separation may occur on the blade suction side, seriously degrading the turbine’s aerodynamic efficiency. The present study investigates a passive flow separation control method based on the oblong dimple surface structures for their more potent flow acceleration abilities. Large eddy simulations are conducted for a typical LPT blade profile, T106A, at Reynolds numbers of 25,000, 50,000, and 100,000 based on the inlet velocity and axial chord length. Numerical results achieve a maximum reduction of aerodynamic loss by 29.5% after applying the oblong dimples at low Reynolds numbers. The vortex visualization identifies two working modes of the oblong dimples. At low Reynolds num-bers, the oblong dimples accelerate the fluid above, generating local high-speed regions, and the uneven velocity distributions in the spanwise direction feed the deformation and fragmentation of the downstream separating vortex. While at high Reynolds numbers, the dimples act as vortex generators, leading to a rapid transition on the blade suction surface.

Keywords: Turbines, Computational Fluid Dynamics
Abstract: Modern rocket engines are demanded to operate at different conditions depending on the flight situations, such as launch and landing. In rocket engine systems, turbines are one of the key components since it determines the pressure in the feedline systems and the efficiency of the rocket system itself. For a better understanding of flow structures in a supersonic turbine in rocket engines, the present study demonstrates numerical simulations of a supersonic rocket engine turbine designed for the DLR LUMEN (Liquid Upper Stage Demonstrator Engine) project, of which the focus is to investigate dynamic behaviors of whole systems of a liquid rocket engine as well as its individual component such as combustor, thrust chamber, and turbopump. The 3D URANS simulations of the LUMEN turbine are carried out at two different operating conditions (nominal and throttling conditions) to investigate flow features at nominal and throttling operations.

Keywords: Axial Compressors, Unsteady Flow and Stability Enhancement in Compressor Flow Control, Others (Aerodynamics and Design)
Abstract: The circumferential bowing of stator blade is known to possess the ability to suppress the corner separation. To enhance the improvement of the aerodynamic performance of axial compressors by the application of the bowed stator blade, the optimizations of blade shape have been studied by many researchers. In most of these studies, the blade root fillets which exist in actual compressors were neglected. However, it was reported that the stator blade root fillets influence the generation of the corner separation in the compressor which has the conventional stator blades. Therefore, the stator blade root fillets can contribute to the improvement of the aerodynamic performance due to the bowed stator. In this study, the influences of the root fillets and the positive dihedral angle of the bowed stator blade on the overall performances and the internal flow behavior of low-speed single-stage axial compressors were clarified.

Keywords: Axial Compressors, Computational Fluid Dynamics
Abstract: The high-performance aero engines handle the maximum possible airflow rates for a given frontal area using high-speed compressors. The Mach number in these compressors goes subsonic at the hub to supersonic at the tip, resulting in the complex shock system deteriorating the blade's aerodynamic performance and structural integrity. The present study focuses on the unsteady nature of the shock and evolving flow physics due to its interaction with the core flow at the near-stall condition. The study is performed using steady and unsteady numerical simulations and validated against the experimental data. The analysis showed that high-intensity shock is confined to the tip region, creating shock-induced boundary layer separation. The tip shock keeps oscillating and eventually disappears with the stall onset, leading to fluctuations in the blade loading. Shock-induced leading edge separation near the hub causes radial migration of the flow, which in turn interacts with the tip leakage flow, casing boundary layer, and suction surface blade boundary layer, forming a large recirculation zone in the blade tip vicinity. The rotor disturbances get convected down to the stator, inducing tip-corner separation.

Keywords: Axial Compressors, Others (Aerodynamics and Design)
Abstract: In this paper, an optimum design method for the asymmetric end wall of an axial flow compressor is developed and applied to the optimum design of a supersonic compressor. The method is based on the Bezier surface to control the root profile of the supersonic compressor rotor. The optimized solution is obtained by changing the control points of the Bezier surface during the optimization process. It has the advantages of fewer optimization variables and a smooth surface. The optimization results show that the non-axisymmetric end walls have an effect on the shock structure of the supersonic rotor and restrain the radial migration flow of the rotor. Finally, the peak isentropic efficiency of the optimized high-load supersonic compressor is increased by 0.6%, which verifies the effectiveness of the optimization method.

Keywords: Turbines, Computational Fluid Dynamics, Others (Aerodynamics and Design)
Abstract: The evolution process of hot streaks in a multi-stage turbine is an important issue for the blade cooling design. The hot streaks are generated in the combustor and change the heat load of the blade rows. Traditionally, this effect is studied by numerically or experimentally comparing different typical inlet temperature distributions. Based on the authors’ previous work, the adjoint method is used in the multi-stage calculation to predict the evolution of the temperature non-uniformity of any form. It is shown that the relationship between the downstream and inlet temperature non-uniformity is almost linear. Therefore, once the derivatives of the downstream temperature to the inlet temperature distribution is obtained, one can predict the downstream temperature at arbitrary inlet boundary conditions. The downstream blade surface is divided into several pieces to describe the downstream temperature distributions using their averaged temperature, because in adjoint method the objective must be a scalar.

Keywords: Unsteady Flow and Flow Control in Turbine, Turbines, Advanced Measurement Techniques
Abstract: The present study focuses on the influence of the trailing edge shape and on the development of coherent structures in the transonic flow of a turbine blade passage. Experiments were performed in the High-speed Cascade Wind Tunnel of the University of the Bundeswehr Munich on a high pressure turbine linear cascade. Engine-relevant flow conditions are examined at a constant exit Reynoldys number of Re_2th = 1,200,000 and a range of exit Mach numbers from Ma_2th= 0.80 to 1.10. The aerodynamic characteristics of the highly unsteady flow is qualitatively investigated using a five hole wedge probe and Particle Image Velocimetry (PIV). By means of a Proper Orthogonal Decomposition (POD) analysis, dominant flow structures are extracted. The near wake flow and shear layer dynamics as well as the evaluation of the wake downstream of the two trailing edge designs are examined. The results show performance benefits due to the mitigation of coherent structures for exit Mach numbers below Ma2th= 1.00 for the profiled trailing edge geometry. For higher exit Mach numbers the round trailing edge has a performance advantage as the strength of the main shock increases and seems to play a dominate role on the integral losses.

Keywords: Turbines, Computational Fluid Dynamics, Others (Aerodynamics and Design)
Abstract: The effect of the axial-velocity-density-ratio (AVDR) on the T106A low-pressure turbine cascade is investigated by comparing the results of full 3D RANS (F3D) simulations with quasi-3D simulations (Q3D) and experiments from the literature. An estimate of AVDR from F3D simulations is used to provide boundary conditions for Q3D. This is found to be sufficient to obtain values of the pressure coefficient cp, boundary layer momentum thickness θ and the shape factor H12 which are found to compare well with experimental results. The influence of the AVDR on the transition behaviour of the LP blade is found to be significant, and recommendations for subsequent work are made.

Keywords: Centrifugal and Mixed-Flow Compressors
Abstract: In this paper, a mixed compressor with transonic inlet condition and a centrifugal compressor with subsonic inlet condition are selected to study the effect of Reynolds number on their performance. The performance of these two compressors are numerical simulated after experimental validation from 1 to 0.1 reference Reynold numbers. The performance of the transonic mixed compressor and subsonic centrifugal compressors decreases by 3.4% and 2.3% respectively at 0.1 reference Reynolds number. Although the performance decrease of the impeller with subsonic inlet condition occurs later than that of the mixed impeller with transonic inlet condition, the performance decrease trends of the two impellers are basically the same. On the contrary, the loss inside the diffuser of mixed compressor increases more obviously than that of centrifugal compressor, which results in a significantly lower performance, under low Reynolds number. Further, based on the local dissipation rate, the change of enthalpy loss from different sources inside these two compressors as the Reynolds number varies is discussed and the performance decrease is related to the secondary structure and flow mechanism. The increase of boundary layer loss is the mainly source for impeller performance decrease when Reynolds number is low.

Keywords: Gas Turbines for Electric Power Generation, Gas Turbine Performance, Unsteady Flow and Flow Control in Turbine
Abstract: Ground-based heavy-duty gas turbines have higher and higher requirements for efficiency, and stricter exhaust emission standards. The cooling of the hot-end components is more ensured by the cold air extracted from the interstage of the compressor to meet the ever-increasing temperature environment before the turbine. The external secondary air system of gas turbines is becoming an important means of current research to improve the working conditions of turbines and compressors. Aiming at a F-class heavy-duty gas turbine, this paper proposes an optimal matching method for the secondary air system based on genetic algorithm. Starting from the gas turbine external extraction channel, the flow pressure distribution of the pipeline and the matching characteristics of the turbine and the compressor are optimized. The results of modular dynamic model analysis and CFD verification show that the optimized secondary air system reduces the cooling flow required by the turbine, improves the surge margin of the compressor, and makes the flow extraction between the compressor stages reasonable. Distribution, the loss has been significantly reduced in the specified constraint optimization space, which provides a reference for the design of heavy-duty gas secondary air system.

Keywords: Gas Turbines for Electric Power Generation, Turbines, New Testing Technology
Abstract: This paper introduces the novel Rotating Turbine Rig (RTR) and the results of the first measurement campaign. The turbine test facility (NG-Turb) at DLR Göttingen and the setup of the RTR are described. The results contain the commissioning of the turbine and investigate the homogeneity of the in- and outflow as well as the repeatability on different test days. Subsequently, inter-blade flow fields are presented and discussed in detail. In sum, high resolution data was recorded and is being used to foster the understanding of multi-stage turbine flow and to validate numerical simulations.

Keywords: Gas Turbines for Electric Power Generation, Development and Operation
Abstract: This work presents the development of a gas turbine simulator based on an application of a real turbogenerator used to generate electricity on an offshore oil platform, a turboshaft with free power turbine. Compressor, turbines and the control system were developed using specific methodologies. The development of the simulator was done using the Simulink environment in Matlab. The development was done using blocks to represent each one of the main components in the engine. A stage stacking methodology based on the real geometry for each stage was adopted to create the compressor maps. The map was used in lookup tables blocks with help of auxiliary coordinates, also known as beta lines. To model both turbines were applied an ellipse equation also known as Stodola’s law. The engine simulator model was tested in an open loop and the results evaluated with the manual data from the engine.

Keywords: Gas Turbines for Mechanical Drive, Aeroderivative Gas Turbines, Others (Combustion, Fuel and Emissions)
Abstract: Over the last five decades of the LNG industry, there has been a significant evolution in the drivers used to power the refrigeration compressors, spanning a wide range of solutions including stream turbines, heavy duty or aeroderivative gas turbines (GT), electric motors, and their combinations [1]. The trend is currently driven by the need to reduce greenhouse gas emissions.

A viable solution to reduce the CO2e/tonne LNG produced of LNG liquefaction plants with GT drivers is to utilize bottoming power cycle(s) (e.g., Steam Rankine Cycle or Organic Rankine Cycle) to recover the waste heat energy from the GT exhaust gases. Other options include a combination of hybrid drives (e.g., GT and steam turbine, or GT and motor) for the refrigeration compressors. This paper is intended to describe opportunities, challenges, and design options for decarbonization of LNG liquefaction plants by focusing on gas turbine drivers of refrigeration compressors. It describes different design options for reducing carbon emissions in both brownfield and greenfield LNG liquefaction plants. Also covered are different design options for CO2 compression systems in LNG liquefaction plants, and compression pathways from subcritical to supercritical conditions.

Keywords: Others (Aircraft Engines)
Abstract: In recent years, reducing emissions such as CO2 and NOx from gas turbines and industrial applications has become an urgent issue toward realizing a carbon-neutral society wherein greenhouse gas emissions are reduced to net-zero. Therefore, there is a strong need to develop and select optimum operating conditions for gas turbines to further improve their efficiency and reduce their emissions. In this panel discussion, future prospects of gas turbine combustion towards carbon-neutral society will be discussed, especially in terms of the utilization of carbon-free fuels. The panel discussion will be divided into two parts, namely “Part 1: Aircraft Gas Turbine” and “Part 2: Industrial Gas Turbine”, and the discussion specialized to each field will be held.

Keywords: Others (Industrial Gas Turbine and Power Systems)
Abstract: In recent years, reducing emissions such as CO2 and NOx from gas turbines and industrial applications has become an urgent issue toward realizing a carbon-neutral society wherein greenhouse gas emissions are reduced to net-zero. Therefore, there is a strong need to develop and select optimum operating conditions for gas turbines to further improve their efficiency and reduce their emissions. In this panel discussion, future prospects of gas turbine combustion towards carbon-neutral society will be discussed, especially in terms of the utilization of carbon-free fuels. The panel discussion will be divided into two parts, namely “Part 1: Aircraft Gas Turbine” and “Part 2: Industrial Gas Turbine”, and the discussion specialized to each field will be held.