Готові списки джерел за темами / Blade channel

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Добірка наукової літератури з теми "Blade channel"

Автор: Grafiati

Опубліковано: 30 травня 2022

Оновлено: 31 травня 2022

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Статті в журналах з теми "Blade channel"

Tao, Ran, and Zhengwei Wang. "Comparative modeling and analysis of the flow asymmetricity in a centrifugal pump impeller at partial load." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 234, no. 2 (May 29, 2019): 237–47. http://dx.doi.org/10.1177/0957650919851921.

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Undesirable flow regime occurs at partial-load conditions of the centrifugal pump. Flow separates at the leading edge and pulses in the blade channel with complex stall cell transfer law. The passing capability of the blade channel becomes important when rotating stall happens. In this study, the blade channel number influence on the flow stability in a centrifugal pump impeller was studied by unsteady flow simulations after numerical-experimental verification. The 5-, 6-, and 7-blade impellers were discussed under the same partial-load flow rate condition and the same rotating speed. Results show that the internal flow pattern was strongly influenced by the blade channel number. Periodic half-blockage was observed in the 5-blade impeller. Alternating stall with three stalled and three well-behaved channels existed in the 6-blade impeller. Complex aperiodic flow pattern occurred in the 7-blade impeller with the well-behaved, half-blocked, and fully stalled passages were all observed with stall cell transfer. The different flow regime caused different pressure pulsations. In the 5-blade impeller, the inter-channel flow frequencies, which were induced by the fluid extruded from blocked channels flowed into other channels, dominated. In the 6-blade impeller, the pressure pulsations performed low-in-amplitude and high-in-frequency. The flow regime was stable even under the rotating stall. In the 7-blade impeller, the rotating stall frequency dominated. The inter-channel flow frequencies were also obvious. The stable rotating stall pattern does not strongly influence the pressure pulsation and impeller axial and radial forces. The transferring stall cell induces extra mild pressure pulsation and impeller forces. The inter-channel flow adds strong pressure pulsation and impeller forces. When centrifugal pumps are operating at partial-load conditions, the flow characters especially the inter-channel flow caused by half-channel-blockage should be checked to avoid operation instability and security.

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Gribin, Vladimir, Ilya Gavrilov, Aleksandr Tishchenko, Victor Tishchenko, Vitaliy Popov, Sergey Khomyakov, and Roman Alexeev. "Features of liquid phase movement in the inter-blade channel of nozzle blade cascade." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 232, no. 5 (September 13, 2017): 452–60. http://dx.doi.org/10.1177/0957650917730947.

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The experimental results of wet steam flow in the blade channel of flat nozzle blade cascade have been considered in the paper. The aim of this work is to study the motion of liquid droplets inside the inter-blade channel. Experimental studies were performed on installation circuit of wet steam. In order to obtain velocity fields of droplets in investigated channel, the laser diagnostics system was used. It carries out the cross-correlation method—particle tracking velocimetry. Numerical simulation of wet steam flow in studied channel was performed. According to the obtained data, the main features of the droplets motion in the blade channel have been revealed. Basic droplets streams and the sources of their appearance have been determined. The process of deposition and breakdown of the droplets on the surface of the blades have been studied. It is shown that reflected region of droplets (“fountain”) is formed around the leading edge. The experimental data were compared with the results of numerical simulation of the droplets motion in the flat nozzle blade cascade.

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Wang, Meng-Hui, Shiue-Der Lu, Cheng-Che Hsieh, and Chun-Chun Hung. "Fault Detection of Wind Turbine Blades Using Multi-Channel CNN." Sustainability 14, no. 3 (February 4, 2022): 1781. http://dx.doi.org/10.3390/su14031781.

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This study utilized the multi-channel convolutional neural network (MCNN) and applied it to wind turbine blade and blade angle fault detection. The proposed approach automatically and effectively captures fault characteristics from the imported original vibration signals and identifies their state in multiple convolutional neural network (CNN) models. The result obtained from each model is sent to the output layer, which is a maximum output network (MAXNET), to compute the most accurate state. First, in terms of wind turbine blade state detection, this paper builds blade models based on the normal state and three common fault types, including blade angle anomaly, blade surface damage, and blade breakage. Vibration signals are employed for fault detection. The proposed wind turbine fault diagnosis approach adopts a triaxial vibration transducer and frame grabber to capture vibration signals and then applies the new MCNN algorithm to identify the state. The test results show that the proposed approach could deliver up to 87.8% identification accuracy for four fault types of large wind turbine blades.

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Ben-Mansour, R., and L. Al-Hadhrami. "Effect of Reynolds Number and Property Variation on Fluid Flow and Heat Transfer in the Entrance Region of a Turbine Blade Internal-Cooling Channel." International Journal of Rotating Machinery 2005, no. 1 (2005): 36–44. http://dx.doi.org/10.1155/ijrm.2005.36.

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Internal cooling is one of the effective techniques to cool turbine blades from inside. This internal cooling is achieved by pumping a relatively cold fluid through the internal-cooling channels. These channels are fed through short channels placed at the root of the turbine blade, usually called entrance region channels. The entrance region at the root of the turbine blade usually has a different geometry than the internal-cooling channel of the blade. This study investigates numerically the fluid flow and heat transfer in one-pass smooth isothermally heated channel using the RNGk−εmodel. The effect of Reynolds number on the flow and heat transfer characteristics has been studied for two mass flow rate ratios (1/1and1/2) for the same cooling channel. The Reynolds number was varied between10 000and50 000. The study has shown that the cooling channel goes through hydrodynamic and thermal development which necessitates a detailed flow and heat transfer study to evaluate the pressure drop and heat transfer rates. For the case of unbalanced mass flow rate ratio, a maximum difference of8.9% in the heat transfer rate between the top and bottom surfaces occurs atRe=10 000while the total heat transfer rate from both surfaces is the same for the balanced mass flow rate case. The effect of temperature-dependent property variation showed a small change in the heat transfer rates when all properties were allowed to vary with temperature. However, individual effects can be significant such as the effect of density variation, which resulted in as much as9.6% reduction in the heat transfer rate.

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Zhang, Jinfeng, Guidong Li, Jieyun Mao, Shouqi Yuan, Yefei Qu, and Jing Jia. "Effects of the outlet position of splitter blade on the flow characteristics in low-specific-speed centrifugal pump." Advances in Mechanical Engineering 10, no. 7 (July 2018): 168781401878952. http://dx.doi.org/10.1177/1687814018789525.

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To elucidate the influences of the outlet position of splitter blades on the performance of a low-specific-speed centrifugal pump, two different splitter blade schemes were proposed: one located in the middle of the channel and the other having a deviation angle at the trailing edge of splitter blade toward the suction side of the main blade. Experiments on the model pump with different splitter blade schemes were conducted, and numerical simulations on internal flow characteristics in the impellers were studied by means of the shear stress transport k- ω turbulence model. The results suggest that there is a good agreement between the experimental and numerical results. The splitter blade schemes can effectively optimize the structure of the jet-wake pattern and improve the internal flow states in the impeller channel. In addition, the secondary flow and inlet circulation on the pressure surface of main blade, the flow separation on the suction side of splitter blade, the pressure coefficient distributions on blade surface can achieve an evident amelioration when the trailing edge of splitter blade toward the suction side of the main blade is mounted at an appropriate position.

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Zhao, Wenbin, Jianbin Hu, and Kai Wang. "Influence of Channel-Diffuser Blades on Energy Performance of a Three-Stage Centrifugal Pump." Symmetry 13, no. 2 (February 5, 2021): 277. http://dx.doi.org/10.3390/sym13020277.

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In order to improve hydraulic efficiency, influence of inlet angle, outlet angle, wrap angle, inlet shape and outer edge camber lines of channel-diffuser blades on the energy performance of a three-stage centrifugal pump were studied and the pressure distributions on the blade of the first-stage channel-diffuser were particularly analyzed. The result shows that the efficiency of the pump is maximal when the blade inlet angle is 12°. The pressure variation in the model with the inlet angle of 12° was small and the amplitude of fluctuation was also not large. When the outlet angle was 90°, the pressure distribution in the outlet of the blades that are symmetrically distributed along the center of the diffuser shell was significantly better than that with other outlet angles. The effect of the blade wrap angle of the channel-diffuser on the energy performance of the pump was relatively small. The internal flow in the diffuser with the diffusion inlet shapes was steady for both the convex surface and concave surface. The diffusion inlet of the channel-diffuser blade corresponded to the outlet region of the impeller blade, which reflected a good matching. The fluctuation amplitude and the distribution range of the models with a uniform transition were smaller than those with non-uniform transition. In order to verify the effectiveness of the research results, an experimental test was carried out on the pump. The results show that when the flow rate is 850 m3/h, the head of the pump is 138.67 m and the efficiency of pump is 69.48%.

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Khalatov, A. A., A. S. Kovalenko, and S. B. Reznik. "FEATURES OF ORGANIZATION OF FILM COOLING OF HIGH TEMPERATURE GAS TURBINES BLADES." Industrial Heat Engineering 39, no. 4 (March 24, 2017): 11–20. http://dx.doi.org/10.31472/ihe.4.2017.02.

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The features of the release of the cooling air in the interscapular channel high temperature gas turbines at the film cooling are considered. Possibilities of its local distribution on contour of an entrance edge of the perforated blades are investigated. The presented calculations show that the substantial increase in the cooling efficiency can be attained due to channels of small dimension in the blade wall.

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Wang, Peng, Xinyu Zhu, and Yi Li. "Analysis of Flow and Wear Characteristics of Solid–Liquid Two-Phase Flow in Rotating Flow Channel." Processes 8, no. 11 (November 21, 2020): 1512. http://dx.doi.org/10.3390/pr8111512.

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To study the flow characteristics and the wear distribution of pumps at different rotation speeds, a rotating disc with three blades was designed for experiments. Numerical simulations were conducted using a computational fluid dynamics-discrete phase model (CFD–DPM) approach. The experimental and numerical results were compared, and the flow characteristics and wear behaviors were determined. As the speed increased, the particles at the blade working surface aggregated. The particle velocity gradually increased at the outlet of the channel. The severe wear areas were all located in the outlet area of the blade working surface, and the wear area extended toward the inlet area of the blade with increasing speed. The wear rate of the blade surface increased as the speed increased, and an area with a steady wear rate appeared at the outlet area of the blade. When the concentration was more than 8%, the severe wear areas were unchanged at the same speed. When the speed increased, the severe wear areas of the blade produced wear ripples, and the area of the ripples increased with increasing speed. The height difference between the ripples along the flow direction on the blade became larger as the speed increased.

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Shi, Lijian, Changxin Wu, Li Wang, Tian Xu, Yuhang Jiang, Yao Chai, and Jun Zhu. "Influence of Blade Angle Deviation on the Hydraulic Performance and Structural Characteristics of S-Type Front Shaft Extension Tubular Pump Device." Processes 10, no. 2 (February 8, 2022): 328. http://dx.doi.org/10.3390/pr10020328.

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When the axial-flow pump is running, the blade angle is not fully adjusted or there are errors in the manufacture of the blades, which will lead to inconsistent blade placement angles during operation, and which will reduce the efficiency of the axial-flow pump. This paper uses the research methods of numerical simulation and model experiments to analyze the hydraulic performance and impeller structure characteristics of each flow components under different schemes when the angles of each blade of the S-type front shaft extension tubular pump device are inconsistent. The research phenomenon is that the guide vane greatly recovers the flow velocity circulation at the impeller outlet, reduces the hydraulic loss of guide vane, and widens the best efficiency range with an increase in guide vane blade angle. When the blade angle deviation occurs, the flow field of each blade channel affects each other, and the maximum decrease in the best efficiency is up to 7.78%, mainly due to the increased hydraulic loss in the outlet channel. The blade angle deviation will also affect the maximum equivalent stress and maximum deformation of the impeller, which is more obvious in large flow conditions. Inconsistent blade angles seriously affect the operating efficiency of the water pump and water pump device, and make the structural characteristics of the impeller worse.

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Luxa, Martin. "The Sonic Surface in the Inter-Blade Channel of the Last Stage Rotor Wheel in the Steam Turbine of Large Output." MATEC Web of Conferences 168 (2018): 02006. http://dx.doi.org/10.1051/matecconf/201816802006.

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The paper deals with sonic surface in a modern turbine wheel consisting of non-prismatic ultra long blades. The whole inter-blade channel is choked. Different positions and shapes of the sonic line in particular cross-sections along the span are observed. The sensitivity of sonic line formation to small changes of effective shape of the inter-blade channel in the root section and the influence of inlet angle, stagger angle and pitch/chord ratio in the tip section are discussed. The problematic of sonic line development in the case of supersonic inlet flow filed is also described. The presented work is based on results of theoretical, experimental and numerical approaches.

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Дисертації з теми "Blade channel"

Karpik, A., and Yu Vorobiev. "Nonlinear Analysis of Gas Flow in Compressors Stage Based on CFD-Method." Thesis, NTU "KhPI", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/24955.

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The numerical simulation of a three-dimensional viscous flow in cascade of the axial compressor of low pressure of the gas-turbine engine is presented. The results of a flow in the first stage o f the compressor in nonstationary three-dimensional statement are obtained in the solver F. Velocity and pressure fields are received as a result.

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Ricklick, Mark. "CHARACTERIZATION OF AN INLINE ROW IMPINGEMENT CHANNEL FOR TURBINE BLADE COOLING APPLICATIONS." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2696.

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Gas turbines have become an intricate part of today's society. Besides powering practically all 200,000+ passenger aircraft in use today, they are also a predominate form of power generation when coupled with a generator. The fact that they are highly efficient, and capable of large power to weight ratios, makes gas turbines an ideal solution for many power requirement issues faced today. Designers have even been able to develop small, micro-turbines capable of producing efficient portable power. Part of the turbine's success is the fact that their efficiency levels have continuously risen since their introduction in the early 1800's. Along with improvements in our understanding and designs of the aerodynamic components of the turbine, as well as improvements in the areas of material design and combustion control, advances in component cooling techniques have predominantly contributed to this success. This is the result of a simple thermodynamic concept; as the turbine inlet temperature is increased, the overall efficiency of the machine increases as well. Designers have exploited this fact to the extent that modern gas turbines produce rotor inlet temperatures beyond the melting point of the sophisticated materials used within them. This has only been possible through the use of sophisticated cooling techniques, particularly in the 1st stage vanes and blades. Some of the cooling techniques employed today have been internal cooling channels enhanced with various features, film and showerhead cooling, as well as internal impingement cooling scenarios. Impingement cooling has proven to be one of the most capable heat removal processes, and the combination of this cooling feature with that of channel flow, as is done in impingement channel cooling, creates a scenario that has understandably received a great deal of attention in recent years. This study has investigated several of the unpublished characteristics of these impingement channels, including the channel height effects on the performance of the channel side walls, effects of bulk temperature increase on heat transfer coefficients, circumferential heat variation effects, and effects on the uniformity of the heat transfer distribution. The main objectives of this dissertation are to explore the various previously unstudied characteristics of impingement channels, in order to sufficiently predict their performance in a wide range of applications. The potential exists, therefore, for a designer to develop a blade with cooling characteristics specifically tailored to the expected component thermal loads. Temperature sensitive paint (TSP) is one of several non-intrusive optical temperature measurements techniques that have gained a significant amount of popularity in the last decade. By employing the use of TSP, we have the ability to provide very accurate (less than 1 degree Celsius uncertainty), high resolution full-field temperature measurements. This has allowed us to investigate the local heat transfer characteristics of the various channel surfaces under a variety of steady state testing conditions. The comparison of thermal performance and uniformity for each impingement channel configuration then highlights the benefits and disadvantages of various configurations. Through these investigations, it has been shown that the channel side walls provide heat transfer coefficients comparable to those found on the target surface, especially at small impingement heights. Although the side walls suffer from highly non-uniform performance near the start of the channel, the profiles become very uniform as the cross flow develops and becomes a dominating contributor to the heat transfer coefficient. Increases in channel height result in increased non-uniformity in the streamwise direction and decreased heat transfer levels. Bulk temperature increases have also been shown to be an important consideration when investigating surfaces dominated by cross flow heat transfer effects, as enhancements up to 80% in some areas may be computed. Considerations of these bulk temperature changes also allow the determination of the point at which the flow transitions from an impingement dominated regime to one that is dominated by cross flow effects. Finally, circumferential heat variations have proven to have negligible effects on the calculated heat transfer coefficient, with the observed differences in heat transfer coefficient being contributed to the unaccounted variations in channel bulk temperature.
Ph.D.
Department of Mechanical, Materials and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering PhD

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Roclawski, Harald. "PIV Measurements of Channel Flow with Multiple Rib Arrangements." UKnowledge, 2001. http://uknowledge.uky.edu/gradschool_theses/303.

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A model of a gas turbine blade cooling channel equipped with turbulators and a backward facing step geometry was examined. Up to four turbulators oriented cross-stream and inclined 45° to the flow direction were mounted in the channel. The blockage ratio b/H of the turbulators and the height h/H of the backward facing step was 0:125 and 0:14 respectively. The number of turbulators as well as their size was varied. In a preliminary investigation, hot-wire and pressure measurements were taken for three different Reynolds numbers (5,000, 12,000, 18,000)in the center plane of the test section. Subsequently, particle image velocimetry (PIV) measurements were made on the same geometries. Results of PIV measurements for a Reynolds number range of Reb=600 to 5,000 for the turbulators and Reh=1,500 to 16,200 for the backward facing step are presented, where Reynolds numbers are based on turbulator height b and step height h, respectively. Plots of the velocity field, vorticity, reverse flow probability and RMS velocity are shown. The focus is on the steady flow behavior but also the unsteadiness of the flow is discussed in one section. Also reattachment lengths were obtained and compared among the various turbulator arrangements and the backward facing step geometry. It was found that the flow becomes periodic after three or four ribs. For one turbulator, a very large separation region was observed. The magnitude of the skin friction factor was found to be the highest for two ribs. If the first rib is replaced by a smaller rib, the skin friction factor becomes the lowest for this case. Compared to the backward facing step, the flow reattaches earlier for multiple turbulators. A dependency of reattachment length on Reynolds number was not observed.

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Bhattarai, Kripesh. "On the Use of a Digital Communication Channel for Feedback in a Position Control System." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1353512595.

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Rupakula, Venkata Panduranga Praveen. "Determination of heat (mass) transfer from blockages with round and elongated holes in a wide rectangular channel." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4977.

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Mass transfer experiments were conducted to study the thermal performance characteristics of blockages with round and elongated holes, positioned in a 12:1 rectangular channel. Naphthalene sublimation technique was adopted to conduct experiments with four different blockage configurations, flow rates corresponding to Reynolds numbers (based on channel hydraulic diameter) of 7,000 and 17,000, and at three blockage locations. The hole area to channel area ratio for all four blockage configurations was the same at 0.196. The hole width was half the channel height, and the distance between consecutive blockages was twice the channel height. Average heat transfer, local heat (mass) transfer and overall pressure drop results were obtained. The thermal performance for a particular blockage configuration was measured in terms of the heat transfer enhancement and the friction factor ratio. Heat transfer enhancement was measured as a ratio of average Nusselt number on the blockage surface to the Nusselt number for a thermally fully developed turbulent flow in a smooth channel. Results indicate that this ratio ranged between 3.6 and 12.4, while the friction factor ratio varied between 500-1700. The blockage configuration with round holes was found to yield best thermal performance, while the configuration with largest hole elongation was nearly equal in thermal performance. In order to compare different blockage configurations, an average value of upstream and downstream side thermal performances was used. A general downward trend in Nusselt number ratio with elongation of holes was observed on the upstream side and a reverse trend was observed on the downstream side. An upward trend in the Nusselt number ratio with blockage hole elongation on the downstream side of a blockage was primarily due to jet reversal from the downstream blockage and its impingement on the downstream surface of the upstream blockage. Local experiments were performed to compare against the results from average experiments and also to gain insights into the flow behaviour. There was good agreement between the results from local and average mass transfer experiments. The average variation in Nusselt number ratio between local and average mass transfer experiments was about 5.06%.

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Liu, Yao-Hsien. "Heat transfer in leading and trailing edge cooling channels of the gas turbine blade under high rotation numbers." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3196.

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Waidmann, Christian [Verfasser]. "Heat Transfer Measurements in Rotating Turbine Blade Cooling Channel Configurations using the Transient Thermochromic Liquid Crystal Technique / Christian Waidmann." München : Verlag Dr. Hut, 2021. http://d-nb.info/1232847747/34.

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Nagaiah, Narasimha. "Multiobjective Design Optimization of Gas Turbine Blade with Emphasis on Internal Cooling." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5350.

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In the design of mechanical components, numerical simulations and experimental methods are commonly used for design creation (or modification) and design optimization. However, a major challenge of using simulation and experimental methods is that they are time-consuming and often cost-prohibitive for the designer. In addition, the simultaneous interactions between aerodynamic, thermodynamic and mechanical integrity objectives for a particular component or set of components are difficult to accurately characterize, even with the existing simulation tools and experimental methods. The current research and practice of using numerical simulations and experimental methods do little to address the simultaneous “satisficing” of multiple and often conflicting design objectives that influence the performance and geometry of a component. This is particularly the case for gas turbine systems that involve a large number of complex components with complicated geometries. Numerous experimental and numerical studies have demonstrated success in generating effective designs for mechanical components; however, their focus has been primarily on optimizing a single design objective based on a limited set of design variables and associated values. In this research, a multiobjective design optimization framework to solve a set of user-specified design objective functions for mechanical components is proposed. The framework integrates a numerical simulation and a nature-inspired optimization procedure that iteratively perturbs a set of design variables eventually converging to a set of tradeoff design solutions. In this research, a gas turbine engine system is used as the test application for the proposed framework. More specifically, the optimization of the gas turbine blade internal cooling channel configuration is performed. This test application is quite relevant as gas turbine engines serve a critical role in the design of the next-generation power generation facilities around the world. Furthermore, turbine blades require better cooling techniques to increase their cooling effectiveness to cope with the increase in engine operating temperatures extending the useful life of the blades. The performance of the proposed framework is evaluated via a computational study, where a set of common, real-world design objectives and a set of design variables that directly influence the set of objectives are considered. Specifically, three objectives are considered in this study: (1) cooling channel heat transfer coefficient, which measures the rate of heat transfer and the goal is to maximize this value; (2) cooling channel air pressure drop, where the goal is to minimize this value; and (3) cooling channel geometry, specifically the cooling channel cavity area, where the goal is to maximize this value. These objectives, which are conflicting, directly influence the cooling effectiveness of a gas turbine blade and the material usage in its design. The computational results show the proposed optimization framework is able to generate, evaluate and identify thousands of competitive tradeoff designs in a fraction of the time that it would take designers using the traditional simulation tools and experimental methods commonly used for mechanical component design generation. This is a significant step beyond the current research and applications of design optimization to gas turbine blades, specifically, and to mechanical components, in general.
Ph.D.
Doctorate
Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering

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Mhetras, Shantanu. "Experimental study of gas turbine blade film cooling and internal turbulated heat transfer at large Reynolds numbers." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1820.

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Waidmann, Christian [Verfasser], and Jens von [Akademischer Betreuer] Wolfersdorf. "Heat transfer measurements in rotating turbine blade cooling channel configurations using the transient thermochromic liquid crystal technique / Christian Waidmann ; Betreuer: Jens von Wolfersdorf." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2020. http://d-nb.info/122943853X/34.

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Книги з теми "Blade channel"

Gauntt, Randall Owen. The DF-4 fuel damage experiment in ACRR with a BWR control blade and channel box. Washington, DC: Division of Systems Research, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1989.

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Blame teachers: The emotional reasons for educational reform. Charlotte, NC: Information Age Publishing, Inc., 2015.

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Lee, Laura. Blame it on the rain: How the weather has changed history. New York: Harper, 2006.

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Eisler, Riane Tennenhaus. The chalice andthe blade: Our history, our future. Cambridge, Mass: Harper & Row, 1987.

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O'Connell, Anne. Centralizing power, decentralizing blame: What Ontarians say about education reform. Ottawa: Caledon Institute of Social Policy, 1998.

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O'Connell, Anne. Centralizing power, decentralizing blame: What Ontarians say about education reform. Ottawa, Ont: Caledon Institute of Social Policy, 1998.

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Daniel, Elizabeth. Don't blame the tools: The adoption and implementation of managerial innovations. Amsterdam: Elsevier/Cima Pub., 2009.

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Eisler, Riane Tennenhaus. The chalice and the blade: Our history, our future. Cambridge [Mass.]: Harper & Row, 1987.

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Eisler, Riane Tennenhaus. The chalice and the blade: Our history, our future. [San Francisco]: HarperCollins, 1988.

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Частини книг з теми "Blade channel"

Prabhu, A., B. Vasudevan, P. Kailasnath, R. S. Kulkarni, and R. Narasimha. "Blade Manipulators in Channel Flow." In Turbulence Management and Relaminarisation, 97–107. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-83281-9_7.

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Lu, Long, Vinod Yegneswaran, Phillip Porras, and Wenke Lee. "BLADE: Slashing the Invisible Channel of Drive-by Download Malware." In Lecture Notes in Computer Science, 350–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-04342-0_20.

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Zhyrkov, Oleksandr, Oleksandr Usatyi, Olena Avdieieva, and Yuri Torba. "Supersonic Flow in the Blade Channel of the Nozzle with a Rotary Diaphragm at Small Degrees of Opening." In Lecture Notes in Mechanical Engineering, 66–78. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-06044-1_7.

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Blustein, Jeffrey M. "How Forgiveness Changes Blame." In Holding Wrongdoers Responsible, 163–74. New York: Routledge, 2021. http://dx.doi.org/10.4324/9781003231615-15.

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Tilly, Charles. "Credit, Blame, and Social Life." In Collective Violence, Contentious Politics, and Social Change, 383–95. New York, NY: Routledge, 2017.: Routledge, 2017. http://dx.doi.org/10.4324/9781315205021-23.

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Coles-Ritchie, Marilee. "Introduction: Can We Blame the Teachers?" In Inciting Change in Secondary English Language Programs, 1–15. New York: Palgrave Macmillan US, 2009. http://dx.doi.org/10.1057/9780230101074_1.

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Burke, W. Warner. "Robert R. Blake and Jane S. Mouton." In The Palgrave Handbook of Organizational Change Thinkers, 1–10. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-49820-1_4-1.

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Burke, W. Warner. "Robert R. Blake and Jane S. Mouton: Concern for People and Production." In The Palgrave Handbook of Organizational Change Thinkers, 157–66. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-52878-6_4.

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Burke, W. Warner. "Robert R. Blake and Jane S. Mouton: Concern for People and Production." In The Palgrave Handbook of Organizational Change Thinkers, 1–10. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-49820-1_4-2.

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Burke, W. Warner. "Blake, Robert R., and Jane S. Mouton: Concern for People and Production." In The Palgrave Handbook of Organizational Change Thinkers, 1–11. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-49820-1_4-3.

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Тези доповідей конференцій з теми "Blade channel"

Agrawal, Smita, Taiho Yeom, Youmin Yu, Mark North, Terrence Simon, and Tianhong Cui. "The Effects of Agitator Blade Geometry and Configuration for Augmenting Heat Transfer by Agitation in Channel Flows." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-37303.

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Translationally oscillating blades, called agitators, can be used to thoroughly mix the flow inside heat exchanger channels such as those in an electronics module heat sink. Generally, throughflow is provided with an induction fan. Agitation is implemented inside the channel by using either multiple agitator blades, agitator blades with notched edges, full-length long-blade agitators or short-blade agitators. The power needed to drive the agitator blades is dependent on the agitation velocity, geometry and mass. The performance features of a 50mm long agitator blade operating at an oscillation frequency of 500Hz, a 15mm short agitator blade operating at a frequency of 1000Hz, and two blades of length 15mm operating at a frequency of 500 Hz have been compared. Also, runs with other geometric changes, like those with added notches at the tip of the agitator, are made to explore their benefits. The intent is that the notches generate additional vorticity at the channel inlet, which is convected downstream enhancing heat transfer as it passes. Thus, this study numerically finds directions toward optimal agitator configurations and geometries that would give heat transfer augmentation without excessive power input. It was found that a multiple agitator blade configuration containing two short blade agitators operating at frequency 500Hz gives the best performance in terms of heat transfer augmentation when power consumption is considered. Heat flux plots on the channel wall and turbulence kinetic energy plots within the channel have been used to explain the mechanisms of heat transfer augmentation for the various cases.

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Amano, R. S., Krishna Guntur, and Jose Martinez Lucci. "Computational Study of Gas Turbine Blade Cooling Channel." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22920.

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It has been a common practice to use cooling passages in gas turbine blade in order to keep the blade temperatures within the operating range. Insufficiently cooled blades are subject to oxidation, to cause creep rupture, and even to cause melting of the material. To design better cooling passages, better understanding of the flow patterns within the complicated flow channels is essential. The interactions between secondary flows and separation lead to very complex flow patterns. To accurately simulate these flows and heat transfer, both refined turbulence models and higher-order numerical schemes are indispensable for turbine designers to improve the cooling performance. Power output and the efficiency of turbine are completely related to gas firing temperature from chamber. The increment of gas firing temperature is limited by the blade material properties. Advancements in the cooling technology resulted in high firing temperatures with acceptable material temperatures. To better design the cooling channels and to improve the heat transfer, many researchers are studying the flow patterns inside the cooling channels both experimentally and computationally. In this paper, the authors present the performance of three turbulence models using TEACH software code in comparison with the experimental values. To test the performance, a square duct with rectangular ribs oriented at 90° and 45° degree and placed at regular intervals. The channel also has bleed holes. The normalized Nusselt number obtained from simulation are validated with that of experiment. The Reynolds number is set at 10,000 for both the simulation and experiment. The interactions between secondary flows and separation lead to very complex flow patterns. To accurately simulate these flows and heat transfer, both refined turbulence models and higher-order numerical schemes are indispensable for turbine designers to improve the cooling performance. The three-dimensional turbulent flows and heat transfer are numerically studied by using several different turbulence models, such as non-linear low-Reynolds number k-omega and Reynolds Stress (RSM) models. In k-omega model the cubic terms are included to represent the effects of extra strain-rates such as streamline curvature and three-dimensionality on both turbulence normal and shear stresses. The finite volume difference method incorporated with the higher-order bounded interpolation scheme has been employed in the present study. The outcome of this study will help determine the best suitable turbulence model for future studies.

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Benoni, Albert, and Reinhard Willinger. "Design Modification of a Passive Tip-Leakage Control Method for Axial Turbines: Linear Cascade Wind Tunnel Results." In ASME 2013 Turbine Blade Tip Symposium. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/tbts2013-2056.

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Tip-leakage losses can contribute up to one third of the overall losses in unshrouded axial turbine blades. A passive tip-leakage flow control method is used to reduce the tip-leakage loss. Taking into account a modified discharge coefficient model, an inclination of the injection against the tip-leakage flow direction is said to have an even better effect on reducing the tip-leakage loss. To prove the effect, linear cascade measurements have been carried out at three different gap widths from 0.85% to 2.50% chord length. The used geometry is an up-scaled turbine blade tip cross section with weak turning. A single blade is fitted with an injection channel which is inclined by 45° against the tip-leakage flow direction. The flow field of the modified blade was measured 0.31 axial chord length downstream of the cascade using a pneumatic five-hole probe. The tip-leakage loss is reduced by passive tip-injection and further by inclined injection. The reduction can be significant at small gap widths. Detailed results are presented for a gap width of 1.40% chord length.

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Carassale, Luigi, Francesca Coletti, Roberto Guida, Michela Marrè-Brunenghi, and Elena Rizzetto. "Multi-Channel Spectral Analysis of Non-Synchronous Vibrations of Bladed Disks Measured by Blade Tip Timing." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15512.

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Abstract The paper proposes a method for the processing of BTT data deriving from non-synchronous vibrations measured at constant rotor speed by a set of non-uniformly distributed sensors. The sampled data are interpreted as members of a vector space whose characteristics are determined by the signal itself and by sampling pattern. If the signal contains a single harmonic component, its frequency can be estimated through a method that has been named harmonic matching. On the contrary, when more than one harmonic component is present, due to a multi-modal response, a component separation processing is necessary. To this purpose, it is proposed a technique based on the Independent Component Analysis (ICA). This approach is limited to constant speed regime, but has the benefit of using statistical estimators that enable a strong resistance to noise. The method is illustrated using academic examples and is employed to study a flutter-like non-synchronous vibration of a bladed disk.

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Amano, R. S., Krishna Guntur, Jose Martinez Lucci, and Yu Ashitaka. "Study of Flow Through a Stationary Ribbed Channel for Blade Cooling." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23031.

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The firing temperature in gas turbine relates itself directly to the power output and the efficiency of the turbine. The higher the firing (operating) temperatures, higher the wall temperature of blades. However, an increase in the firing temperature is limited by the first stage blade material properties. This is because the higher firing temperature may cause a creep rupture, oxidizing, melting and ultimately failing of blades. Prior to blade cooling, the firing temperature was the same as the blade material temperature. Advancements in cooling technology have resulted in high firing temperatures with acceptable material temperatures. To better design the cooling channels and to improve heat transfer, many researchers are studying the flow patterns inside the cooling channels both experimentally and computationally. In this paper, the authors present the performance of three turbulence models using a Computational Fluid Dynamics code in comparison with the experimental values. To test the performance, a square duct was used with rectangular ribs oriented at 90° and 45° degree and placed at regular intervals. The channel also has bleed holes. The wall Nusselt numbers are compared in both the experimental and the computational results after suitable normalization. The Reynolds number is set to 10,000. The interactions between secondary flows and separation lead to very complex flow patterns. To accurately simulate these flows and heat transfer, both refined turbulence models and higher-order numerical schemes are indispensable for turbine designers to improve the cooling performance. The three-dimensional turbulent flows and heat transfer are numerically studied by using several different turbulence models, such as a non-linear low-Reynolds number k-ω and Reynolds Stress (RSM) models. In the k-ω model the cubic terms are included to represent the effects of extra strain-rates such as streamline curvature and three-dimensionality on both normal and shear turbulence stresses. The finite volume difference method incorporated with the higher-order bounded interpolation scheme has been employed in the present study. The outcome of this study helps to determine the best suitable turbulence model for future studies.

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Sˇimurda, David, Martin Luxa, and Pavel Sˇafarˇi´k. "Aerodynamic Research on the MCA-Type Compressor Blade Cascade." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22153.

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This paper deals with an analysis of the flow through a high cambered compressor blade cascade. The profiles of the blade cascade have been designed to be of MCA-type. The geometric and aerodynamic parameters of the cascade are presented here. The aerodynamic research was performed in a transonic wind tunnel. Optical methods were applied to obtain information on the flow structures taking place in the interblade channels when operating in a range of subsonic and transonic velocities and at various angles of incidence. The internal shock waves and the flow separation in the rear part of the cascade channel were observed and studied. Their influence on the loss coefficient and exit flow angle at subsonic and low transonic region was assessed. The thickness of the sidewall boundary layer in the interblade channel was measured in order to investigate the development of the axial velocity density ratio (AVDR), which plays an important role in the interpretation of the results.

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LeBlanc, Christopher, Srinath V. Ekkad, Tony Lambert, and Veera Rajendran. "Detailed Heat Transfer Distributions in Engine Similar Cooling Channels for a Turbine Rotor Blade With Different Rib Orientations." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45254.

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Detailed Nusselt number distributions are presented for a gas turbine engine similar internal channel geometry used for cooling a modern first stage rotor blade. The cooling design has one leading edge channel and a three-pass channel that covers the rest of the blade. The simulated model, generated from the midspan section of an actual cooling circuit, was studied for wall heat transfer coefficient measurements using the transient liquid crystal technique. The model wall inner surfaces were sprayed with thermochromic liquid crystals, and a transient test was used to obtain the local heat transfer coefficients from the measured color change. Results are presented for a nominal channel inlet leading edge channel Reynolds number of 10700 and a channel inlet three-pass channel Reynolds number of 25500. Detailed heat transfer measurements are presented for the simulated leading edge, first pass, second pass and third pass interior walls for different rib configurations. The channels were studied for smooth, 90° ribs, and angled ribs geometries in addition to ribs on the divider walls between adjacent passages. Overall pressure drop measurements were also obtained for each passage. Some of these results are compared with the predicted heat transfer from standard correlations used in design practices. Results show very complicated heat transfer behavior in these realistic channels compared to results obtained in simplistic geometry channels from published studies. In some cases, the Nusselt numbers predicted by correlations are 50–60% higher than obtained from the current experiments.

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Sharma, Prateek, Bittagopal Mondal, and Gautam Biswas. "Flow and Heat Transfer Characteristics in Ribbed Channel Using Lattice Boltzmann Method." In ASME 2013 Heat Transfer Summer Conference collocated with the ASME 2013 7th International Conference on Energy Sustainability and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ht2013-17676.

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In order to improve the efficiency of the gas turbines and power plants, researchers have aimed to reach higher turbine inlet temperatures. There is always a metallurgical limit for highest temperature, as the materials pertaining to turbine cannot withstand very high temperature due to change in material properties. Deformation, creeping and even melting of turbine blades may occur. To alleviate these, researchers have been trying to evolve the cooling systems for turbine blades. Two major cooling strategies involve (a) external cooling and (b) internal cooling. In case of internal cooling, a layer of air or some coolant is made to flow through small passages inside the blade. Both the systems remove heat from the blade and keep the blade temperature under the metallurgical limit. The present work is aimed at modeling the internal cooling passages of the gas turbine blades. The same geometry can throw light on the performance of cooling passages used in electronic devices. Taking these two applications into consideration, it becomes necessary to study flow and heat transfer past bluff-bodies and in ribbed channels. In the present work, the fluid flow behavior and heat transfer characteristics in a rectangular channel with staggered ribs mounted on both walls are analyzed using the lattice Boltzmann method (LBM). This study is carried out for the fluid with Prandtl number Pr = 0.7 and a wide range of Reynolds numbers (10 ≤ Re ≤ 120). The computational strategy is applied in various test cases and validated with the results reported in the literature. The unsteady flow behaviors, such as, instantaneous streamlines, vortex shedding frequency and phase plots are reported. For the ribbed channel (with staggered ribs), the heat transfer is predicted with the help of isotherms, local Nusselt number distribution and average Nusselt number.

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Hildebrandt, A. "Numerical Analysis of Overall Performance and Flow Phenomena of an Automatically Optimized Three-Dimensional Return Channel System for Multistage Centrifugal Compression Systems." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68559.

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For multi-stage compression systems, besides the aerodynamics of the impeller and the diffuser, the U-turn and return channel blades aerodynamics play an important role for the total stage efficiency of the compression system. Due to modern CAD and CAM methodology, three-dimensional blade surfaces of an impeller but also of return channel blades are easily designed and manufactured at a similar price as old-fashioned two-dimensional blade designs. This paper presents the numerical analysis and aerodynamic optimization of a three-dimensional return channel system for multi stage single shaft centrifugal compressor machinery. In a previous paper, a two-dimensional return channel blade system had been optimized by an automatic evolutionary algorithm [1]. This previous study showed further aerodynamic potential by utilizing a three dimensional return channel blade design. The three-dimensional blade comprises of ruling surfaces. In the present paper, for a three-dimensional blade design, both the blade angle and blade thickness distributions are allowed to be varied independently for the hub and the shroud. As a result, the total pressure loss of the three dimensional return channel blade can be relatively reduced by 6% compared with a classical two-dimensional return channel blade. This reduction in total pressure loss is partly caused by the matching of the leading edge angle to the non-uniform flow angle at the U-turn outlet. Furthermore, the different blade angle distribution helps to suppress flow separation at the blade suction side near the shroud and helps to reduce flow friction on the blade surface near the hub.

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Srinivasan, Balamurugan, Anand Dhamarla, Chandiran Jayamurugan, and Amarnath Balu Rajan. "Numerical Studies on Effect of Channel Orientation in a Rotating Smooth Wedge-Shaped Cooling Channel." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26560.

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The increasing demands of better efficiency of modern advanced gas turbine require higher turbine inlet temperatures, which gives great challenges to turbine blade designers. However, the temperature limits of turbine blade material are not high enough to ensure its survival in such incredible operating temperature. Hence, both internal and external cooling approaches have been developed and widely used in today’s turbine blade. To internal cooling problems, a variety of cooling enhancement approaches, such as impingement and turbulators, are employed in order to meet the different needs in leading, middle and trailing region. One of the most critical parts in turbine blade is trailing edge where it is hard to cool due to its narrow shape. Pin-fins are widely used to cool the trailing edge of rotor and stator blades of gas turbine engine. Pin-fins offer significant heat transfer enhancement, they are relatively easy to fabricate and offer structural support to the hollow trailing edge region. The flow physics in a pin-fin roughened channel is very complicated and three-dimensional. In this work, we have studied the effect of channel orientation on heat transfer in a rotating wedge-shaped cooling channel using numerical methods. Qiu [1] studied experimentally heat transfer effects of 5 different angles of wedge shaped channel orientation for the inlet Reynolds number (5100 to 21000) and rotational speed (zero to 1000 rpm), which results in the inlet Rotation number variation from 0 to 0.68. They observed that compared to the non-rotating condition, there is about 35% overall heat transfer enhancement under highest rotation number. The above said results are validated using current studies with Computational Fluid Dynamics (CFD) revealed that rotation increases significantly the heat transfer coefficient on the trailing surface and reduces the heat transfer coefficient on the leading surface. This is due to the higher velocities associated with the converging geometry near trailing surface.

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Звіти організацій з теми "Blade channel"

Singh, Gyanender, Jacob P. Gorton, Danny Schappel, Benjamin S. Collins, Nicholas R. Brown, and Brian D. Wirth. Impact of Control Blade Insertion on the Deformation Behavior of SiC-SiC Channel Boxes in Boiling Water Reactors. Office of Scientific and Technical Information (OSTI), October 2019. http://dx.doi.org/10.2172/1615808.

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Gauntt, R., R. Gasser, and L. Ott. The DF-4 fuel damage experiment in ACRR (Annual Core Research Reactor) with a BWR (Boiling Water Reactor) control blade and channel box. Office of Scientific and Technical Information (OSTI), November 1989. http://dx.doi.org/10.2172/5101359.

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Schattman, Rachel. Farming the floodplain: New England river governance in a changing climate (Hand-outs). USDA Northeast Climate Hub, November 2017. http://dx.doi.org/10.32747/2017.6956534.ch.

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You are worried about flood impacts from the river that borders your property. While you have considered building a levee and placing stones along the bank to protect you land and house from erosion, you do not have the equipment or expertise to do so. Additionally, you have seen water velocity in the river increase because the farmer upstream has channeled the river. You blame the farmer for putting your land and house at greater flood risk. You think that upstream land should be allowed to flood to slow water velocity and absorb floodwaters; this would protect you and your neighbors from future floods.

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Ding, Yan, Q. Chen, Ling Zhu, Julie Rosati, and Bradley Johnson. Implementation of flexible vegetation into CSHORE for modeling wave attenuation. Engineer Research and Development Center (U.S.), February 2022. http://dx.doi.org/10.21079/11681/43220.

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This technical report presents the new numerical modeling capabilities for simulating wave attenuation and mean water level changes through flexible vegetation such as smooth cordgrass in coastal and marine wetlands. These capabilities were implemented into the Cross-SHORE (CSHORE) numerical model. The biomechanical properties of vegetation such as dimensions, flexibility, and bending strength are parameterized in terms of the scaling law. Correspondingly, a new formulation of the vegetation drag coefficient, CD, is developed using field data from a salt marsh in Terrebonne Bay, LA, by considering spatially varying effective stem and blade heights of species. This report also presents a general procedure for using the model to simulate hydrodynamic variables (i.e., waves, currents, mean water levels) at vegetated coasts, which are used to quantify the effects of wave attenuation and reduction of surge and runup due to vegetation. Preliminary model validation was conducted by simulating a set of laboratory experiments on synthetic vegetation, which mimicked the flexibility of Spartina alterniflora. The validation results indicate that the newly developed vegetation capabilities enable CSHORE to predict changes of wave heights and water levels through marshes by considering species-specific biomechanical features. The model is also applicable to assess vegetation effectiveness against waves and surges.

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Estache, Antonio, and Tomás Serebrisky. Updating Infrastructure Regulation for The 21st Century in Latin America and the Caribbean. Inter-American Development Bank, January 2020. http://dx.doi.org/10.18235/0002159.

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This paper argues that, while most countries in Latin America and the Caribbean have managed to significantly improve the short-term efficiency of their infrastructure services since the widespread liberalization of the 1990s, they have been slow to ensure a fair distribution of the gains. They have also been slow in making the investments needed to ensure the prospects of future generations, including by protecting the environment for the long term. The paper places at least part of the blame on regulatory failures. It also shows how past mistakes can be corrected by the significant sectoral transformations, driven by new technologies, now underway. Digitalization is altering the economic characteristics of infrastructure services. Resulting changes in governance and financing options demand adjustments to economic regulations, including by broadening the regulatory toolkit to integrate new insights offered by developments in behavioral economics.

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Olsson, Olle. Industrial decarbonization done right: identifying success factors for well-functioning permitting processes. Stockholm Environment Institute, November 2021. http://dx.doi.org/10.51414/sei2021.034.

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1 Introduction 1.1 The urgency of industrial decarbonization The last few years have seen several of the world’s largest carbon dioxide-emitting countries and leading heavy industry companies committing to mid-century net-zero targets (Buckley 2021; Denyer and Kashiwagi 2020; McCurry 2020; Myers 2020). Consequently, the discussion on economy-wide transition to net-zero is accelerating, with focus shifting from “if” to “when” and “how”, even for heavy industry sectors like steel, cement and chemicals. This makes it increasingly urgent to analyse not just whether it is technologically feasible to decarbonize heavy industry, but also investigate issues more directly related to practical implementation. This includes site-specific planning, infrastructure availability, and consultation with local authorities and other stakeholders. Many of the latter considerations are formalized as part of the permitting processes that are an essential vehicle to ensure that industrial interests are balanced against interests of society at large. However, doing this balancing act can turn out to be very complicated and associated with uncertainties as to their outcome, as well as being demanding in resources and time. At the same time, to ensure broad buy-in and support from society, the investments needed must be implemented in a way that takes a broad spectrum of sustainability concerns into account, not just climate change mitigation. A key question is if and how permitting processes can run more smoothly and efficiently while still ensuring inclusive consultations, fair procedures and adherence to legal certainty. This policy brief discusses this question from the starting point of Swedish conditions, but many of the points raised will be relevant for a broader international discussion on taking industrial decarbonization to implementation. 1.2 Industrial transition and permitting processes in Sweden Decarbonization of the industrial sector in Sweden essentially entails a relatively small number of investment projects in the cement, steel, petrochemical and refinery sectors, where the vast majority of carbon emissions are concentrated (Karltorp et al. 2019; Nykvist et al. 2020). However, while few in number, the size of these investments means that their implementation will by necessity become relevant to many other parts of society. In connection with the increasing focus on how to implement industrial decarbonization in Sweden, discussions about permitting processes have been brought higher up on the agenda. While there has been an active discussion on permitting processes in Sweden for quite some time, it has primarily been focused on aspects related to mining and wind power (Larsen et al. 2017; Raitio et al. 2020). The last few years have, however, focused increasingly on industrial projects, in particular related to a proposed – though eventually cancelled – expansion of an oil refinery in the southwestern part of the country (Blad 2020). In terms of political discussions, both the governmental initiative Fossil-free Sweden (2020) and the Swedish Climate Policy Council (2020) emphasize that permitting processes need to become faster in order for Sweden’s industrial transition to be implemented in line with the time plan set by the 2017 Swedish Climate Act. Business representatives and organizations are also voicing concerns about the slow speed of permitting (Balanskommissionen 2019; Jacke 2018). At the same time, criticism has been raised that much of the environmental damage done in Sweden comes from activities conducted within limits set by environmental permits, which could be a flaw in the system (Malmaeus and Lindblom 2019). Finally, recent public inquiries have also discussed permitting processes.

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