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Various techniques for manufacturing integrally bladed turbine disks (turbine blisks) are described, followed by a discussion of the development trend of turbine blisk manufacture. Analysis shows that powder metallurgy near‐net‐shape hot isostatic pressing will be the focus of future research for turbine blisk blanking, while electrical discharge machining still will be the most competitive technology for turbine blisk finishing.

The purpose of this paper is to analyze the ability of turbulence models to model the flow field in the runner of a Francis turbine. Although the complex flow in the turbine can be simulated by CFD models, the prediction accuracy still needs to be improved. The choice of the turbulence model is one key tool that affects the prediction accuracy of numerical simulations.

This study used the SST k-w and RNG k-e turbulence models, which can both accurately predict complex flow fields in numerical simulations, to simulate the flow in the entire flow passage of a Francis turbine with the results compared against experimental data for the performance and blade pressure distribution in the turbine to evaluate the applicability of the turbulence models.

The results show that the SST k-w turbulence model more accurately predicts the turbine performance than the RNG turbulence model. However, the blade surface pressures predicted by the SST k-w turbulence model were basically identical to those predicted by the RNG k-e turbulence model, with both accurately predicting the experimental data.

Due to the lack of space, the method used to measure the blade surface pressure distributions is not introduced in this paper.

Turbine performance and flow field pressure in the runner, which are the basis of turbine preliminary performance judgment and optimization through CFD, can be used to judge the rationality of the turbine runner design. The paper provides an evidence for the turbulence selection in numerical simulation to predict turbine performance and flow field pressure in the runner and improves the CFD prediction accuracy.

This paper fulfils a test of the flow field pressure in the runner, which provide an evidence for judge the adaptability of turbulence model on the flow field in runner. And this paper also provides important evaluations of two turbulence models for modeling the flow field pressure distribution in the runner of a Francis turbine to improve the accuracy of CFD models for predicting turbine performance.

The purpose of this paper is to propose a quantitative model for risk-based maintenance and remaining life assessment for gas turbines.

The proposed model uses historical failure and repair data from the operation of gas turbines. The time to failure of gas turbines is modeled using Weibull distribution.

The total risk is estimated considering replacement cost, repair cost, operation cost, risk of failure and turbine remaining value after a specified period of time.

The model is an effective tool to make optimal decisions regarding maintenance strategy (repair or replacement) and to assess the remaining life based on a comparison of the total risk. The literature review focusses on developing different models to make risk-based decisions regarding the selection of a maintenance strategy and maintenance interval, however, literature is silent regarding risk-based assessment of the equipment remaining life, which is the focus of present work. The model is tested and applied to ageing gas turbines in a cross-country pipeline.

MAKERS OF STATIONARY GAS TURBINES for industrial uses claim that the lubricating cost of medium‐size power units ranges between 1 and 2% of the fuel costs. Comparative figures for average Diesel engines are 5 to 10%. These savings have an effect on the total running cost economy. Detailed oil consumption figures from industrial gas turbine operators have not yet been disclosed and for similar reasons, it is not possible in this survey to discuss individual design features of all units which comprise the various lubricating systems.

The purpose of this paper is to perform experiments on a full scale turbine blade attached to a part of actual turbine disc at elevated temperature, which can accurately predict the life of a fir‐tree contact under high cycle fatigue (HCF)/low cycle fatigue (LCF) combined loading. Moreover, the effect of shot‐peening on the fatigue lives of the turbine attachments is investigated experimentally by comparing those of unpeened ones.

An experimental system for a full scale turbine blade attached to a part of actual turbine disc at elevated temperature is established in this paper, with a new HCF/LCF combined loading scheme and a design of blade clamp. The new combined fatigue loading method achieves a noninterfering treatment of the high cycle and low cycle loading by placing low cycle loading exerting point to the back of the mortise. Then fatigue tests were performed on six used turbine components to investigate the effect of shot‐peening on fatigue life compared with the unpeened ones.

This test system ingeniously achieves HCF/LCF combined loading of the full scale turbine component, and a special design of the blade clamp successfully simulates the stress field of the turbine blade. Experimental life data show that the shot‐peening process greatly improves the used turbine fir‐tree attachment's life.

The present study provides an experimental method to simulate HCF/LCF combined loading of a full scale fir‐tree turbine attachment at elevated temperature at laboratory.

Compared with the unpeened turbine components, the fatigue lives of the shot‐peened ones are increased greatly. Mean life of the shot‐peened turbine attachment is 5.23 times longer than that of the unpeened.

Sustainable energy has been on the political agenda in Denmark for decades. This chapter will highlight how wind turbine production quite unforeseen became a great success in Denmark before the turn of the Millennium. An integrative public leadership approach using a mix of supportive institutional designs and instruments, combined with an unexpected bottom-up pressure for alternatives to nuclear power, promoted ways for wind turbine innovation and production in the 1970s. After the turn of the Millennium, being a huge financial success creating many new jobs and export has it developed into a cluster based on huge investments and professionalised developers. The comprehensive transition of wind turbine production in Denmark, from small scale to large scale, has however provided a counterproductive decrease in community commitment for local renewable energy production.

Denmark is known internationally as a climate frontrunner and not only due to wind turbine production and planning. The status is obtained by polycentric governance applied in cooperative-owned energy systems. The Danish response to climate change is a concerted effort of a plethora of public and private actors, providing a crucial momentum and robustness in climate politics not at least generated from a genuine civic society involvement. ‘The Danish Energy Model’; a withhold strategic effort to combine ambitious renewable energy goals, energy efficiency targets and political support of technical and industrial development has for four decades, succeeded in providing high levels of cheap energy supply, while partly reducing fossil fuel dependency at the same time.

This study aims to simulate Hunter turbine in Computer Forensic Examiner (CFX) environment dynamically. For this purpose, the turbine is designed in desired dimensions and simulated in ANSYS software under a specific fluid flow rate. The obtained values were then compared with previous studies for different values of angles (θ and α). The amount of validation error were obtained.

In this research, at first, the study of fluid flow and then the examination of that in the tidal turbine and identifying the turbines used for tidal energy extraction are performed. For this purpose, the equations governing flow and turbine are thoroughly investigated, and the computational fluid dynamic simulation is done after numerical modeling of Hunter turbine in a CFX environment.

The failure results showed; 11.25% for the blades to fully open, 2.5% for blades to start, and 2.2% for blades to close completely. Also, results obtained from three flow coefficients, 0.36, 0.44 and 0.46, are validated by experimental data that were in high-grade agreement, and the failure value coefficients of (0.44 and 0.46) equal (0.013 and 0.014), respectively.

In this research, at first, the geometry of the Hunter turbine is discussed. Then, the model of the turbine is designed with SolidWorks software. An essential feature of SolidWorks software, which was sorely needed in this project, is the possibility of mechanical clamping of the blades. The validation is performed by comparing the results with previous studies to show the simulation accuracy. This research’s overall objective is the dynamical simulation of Hunter turbine with the CFX. The turbine was then designed to desired dimensions and simulated in the ANSYS software at a specified fluid flow rate and verified, which had not been done so far.

Steam turbine final assembly is a dynamic process, in which various interference events occur frequently. Currently, data transmission relies on oral presentation, while scheduling depends on the manual experience of managers. This mode has low information transmission efficiency and is difficult to timely respond to emergencies. Besides, it is difficult to consider various factors when manually adjusting the plan, which reduces assembly efficiency. The purpose of this paper is to propose a knowledge-based real-time scheduling system under cyber-physical system (CPS) environment which can improve the assembly efficiency of steam turbines.

First, an Internet of Things based CPS framework is proposed to achieve real-time monitoring of turbine assembly and improve the efficiency of information transmission. Second, a knowledge-based real-time scheduling system consisting of three modules is designed to replace manual experience for steam turbine assembly scheduling.

Experiments show that the scheduling results of the knowledge-based scheduling system outperform heuristic algorithms based on priority rules. Compared with manual scheduling, the delay time is reduced by 43.9%.

A knowledge-based real-time scheduling system under CPS environment is proposed to improve the assembly efficiency of steam turbines. This paper provides a reference paradigm for the application of the knowledge-based system and CPS in the assembly control of labor-intensive engineering-to-order products.

Fundamentally, it is advantageous to operate an aeroengine's thermodynamic cycle at as high a turbine entry temperature as practical for the current metallurgical limits of the turbine blades in order to achieve peak cycle efficiency and thus lower specific fuel consumption. However, achieving the highest possible turbine entry temperature requires accurate knowledge of the turbine blade temperatures for control purposes to prolong component life as frequent excursions beyond the design limits of the blades can severely reduce their service life. The optical pyrometry technique represents the best method for providing this crucial temperature data needed for blade condition‐based monitoring. This paper presents the general operating principles, system aspects and design considerations for the application of the optical pyrometer instrument for inflight service use on gas turbine aeroengines.

The paper presents a techno-economic analysis of the electromechanical equipment of traditional vertical axis water mills (VAWMs) to help investors, mill owners and engineers to preliminary estimate related benefits and costs of a VAWM repowering.

Two sustainable repowering solutions were examined with the additional aim to preserve the original status and aesthetics of a VAWM: the use of a vertical axis water wheel (VAWW) and a vertical axis impulse turbine. The analysis was applied to a database of 714 VAWMs in Basilicata (Italy), with known head and flow.

Expeditious equations were proposed for both solutions to determine: (1) a suitable diameter as a function of the flow rate; (2) the costs of the electromechanical equipment; (3) achievable power. The common operating hydraulic range of a VAWM (head and flow) was also identified. Reality checks on the obtained results are shown, in particular by examining two Spanish case studies and the available literature. The power generated by the impulse turbine (Turgo type) is twice that of a VAWW, but it is one order of magnitude more expensive. Therefore, the impulse turbine should be used for higher power requirements (>3 kW), or when the electricity is delivered to the grid, maximizing the long-term profit.

Since there is not enough evidence about the achievable performance and cost of a VAWM repowering, this work provides expeditious tools for their evaluation.