Academic literature on the topic 'Double casing turbine'
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Journal articles on the topic "Double casing turbine"
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Bajic´, Branko, and Andreas Keller. "Spectrum Normalization Method in Vibro-Acoustical Diagnostic Measurements of Hydroturbine Cavitation." Journal of Fluids Engineering 118, no. 4 (December 1, 1996): 756–61. http://dx.doi.org/10.1115/1.2835506.
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Full-scale vibro-acoustical diagnostic measurements of cavitation in four Francis 6 MW double runner turbines were performed. Two types of sensors were used—a hydrophone sensing waterborne noise at the pressure side of a runner and an accelerometer mounted at various points at the outer turbine casing, facing the runner’s pressure side. The correlation of noise and acceleration intensity with suction-side pressure fluctuations and runner position was checked. A simple but efficient method of spectrum normalization, which rejects the influence of the measurement set characteristics and vibro-acoustical characteristics of a turbine, was developed. The resulting spectra reveal the dependence of cavitation source strength on the turbine power as a function of noise or acceleration frequency.
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Mohammed Menaouar, Bencherif, Hamel Mohamed, Bencherif Mohamed, Guelailia Ahmed, and Hamidou Mohamed Kamel. "The separation wall effect of a volute twin entry cross section area on the mixed inflow turbine performance." Engineering review 41, no. 1 (2020): 11–20. http://dx.doi.org/10.30765/er.1383.
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The pulse turbocharging system is used in many diesel engines and it is fortunate that nozzleless mixed turbines allow unsteady flow with less performance losses. It operates with a double or sometimes triple-entry casing creating different flow regimes in each sector. A nozzleless casing is used. The division of the cross section area takes the form of a solid wall in the radial plane. When the flow rate through one or the other volute inlet drops to zero, some reverse flow is observed from the other inlet. This situation suffers undesirable effects, diminishing the benefits of the divided volute casing types. A numerical investigation on the effect of the length of the dividing wall in the radial plane is performed using the ANSYS code. This possibility is explored and the results show that extending the wall to a limiting length enhances the flow behavior with better performance.
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Yang, Yang, Huajiang Ouyang, Yiren Yang, Dengqing Cao, and Kai Wang. "Vibration analysis of a dual-rotor-bearing-double casing system with pedestal looseness and multi-stage turbine blade-casing rub." Mechanical Systems and Signal Processing 143 (September 2020): 106845. http://dx.doi.org/10.1016/j.ymssp.2020.106845.
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Wu, Hai Hua, Di Chen Li, and Yi Ping Tang. "Fabrication of Integral Core/Shell Ceramic Casting Mould for Hollow Turbine Blade." Applied Mechanics and Materials 248 (December 2012): 231–36. http://dx.doi.org/10.4028/www.scientific.net/amm.248.231.
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The paper presents an integral core/shell fabrication of ceramic casting mould for hollow turbine blades by combining SL (Stereolithography) with gelcasting. This method could guarantee the positional accuracy between ceramic cores and shell, thus achieving the rapid fabrication of complex turbine blade castings. The paper focuses on the design of resin mould for gelcasting, the preparation of ceramic slurry, the pyrolysis of resin prototype and the sintering of ceramic green body. The feasibility and effectiveness of above mentioned method were verified through successful manufacturing of hollow turbine blades with double-walled structure.
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Min, Chaoqing, Quansheng Li, Xianbin Yang, Xiaodong Wang, Qin Li, Dongxiang Hou, Wenjun Wang, and Xuesong Mei. "Trimming for alumina-based ceramic casting cores for turbine blade by double picosecond laser scanning." Journal of Micromechanics and Microengineering 30, no. 9 (August 5, 2020): 095014. http://dx.doi.org/10.1088/1361-6439/aba170.
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Rantererung, Corvis L., Sudjito Soeparman, Rudy Soenoko, and Slamet Wahyudi. "A Double Nozzle Cross Flow Turbine Fluid Flow Dynamics." Journal of Southwest Jiaotong University 55, no. 4 (2020). http://dx.doi.org/10.35741/issn.0258-2724.55.4.49.
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The dynamics of fluid flow are very important to the process of converting water energy into mechanical energy at the nozzle double runner cross flow turbine blade. Fluid dynamics of a jet of water from a nozzle release energy as the water crosses the cross flow turbine runner. This research aims to improve turbine performance and the effectiveness of fluid flow dynamics that drive cross flow turbine runner blades using double nozzles. The method of research using a cross flow turbine with double nozzle is a combination of vertical and horizontal nozzles. The turbine runner casing and blade are made of transparent acrylic material so that the flow dynamics can be observed directly. The laboratory scale double nozzle cross flow turbine is comprised of 24 blades, 3 mm thick, 40 mm long and 200 mm runner blade diameter. Test the performance of the turbine by measuring rotation, torque, and power, and by photographing the dynamics of the fluid flow that drives the turbine runner blade. The results of the study found that the visualization of the dynamics of fluid flow in turbines with double nozzles is more regular, evenly distributed, focused, and directed, moving the turbine runner blade cross flow so as to be able to increase turbine performance higher. The highest double nozzle cross flow turbine performance is 6.04 Watt power and 81.68% efficiency, at a water discharge of 0.22 liters /s.
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Sangan, Carl M., James A. Scobie, J. Michael Owen, Gary D. Lock, Kok Mun Tham, and Vincent P. Laurello. "Performance of a Finned Turbine Rim Seal." Journal of Turbomachinery 136, no. 11 (August 26, 2014). http://dx.doi.org/10.1115/1.4028116.
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In gas turbines, rim seals are fitted at the periphery of the wheel-space between the turbine disk and its adjacent casing; their purpose is to reduce the ingress of hot mainstream gases. A superposed sealant flow, bled from the compressor, is used to purge the wheel-space or at least dilute the ingress to an acceptable level. The ingress is caused by the circumferential variation of pressure in the turbine annulus radially outward of the seal. Engine designers often use double-rim seals where the variation in pressure is attenuated in the outer wheel-space between the two seals. This paper describes experimental results from a research facility that models an axial turbine stage with engine-representative rim seals. The radial variation of CO2 gas concentration, swirl, and pressure, in both the inner and outer wheel-space, are presented over a range of purge flow rates. The data are used to assess the performance of two seals: a datum double-rim seal and a derivative with a series of radial fins. The concept behind the finned seal is that the radial fins increase the swirl in the outer wheel-space; measurements of swirl show the captive fluid between the fins rotate with near solid body rotation. The improved attenuation of the pressure asymmetry, which governs the ingress, results in an improved performance of the inner geometry of the seal. The fins also increased the pressure in the outer wheel-space and reduced the ingress though the outer geometry of the seal.
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Li, Weihang, Shaowen Chen, Hongyan Liu, Zhihua Zhou, and Songtao Wang. "Effects of Double-Side Labyrinth Seals on Aerodynamic Performance in a Transonic Shrouded Turbine Stage." Journal of Engineering for Gas Turbines and Power 142, no. 2 (January 13, 2020). http://dx.doi.org/10.1115/1.4045182.
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Abstract Labyrinth seals on both rotor casing and blade tip as an effective method to control the leakage flowrate of the shroud and improve aerodynamic performances in a transonic turbine stage are investigated in this study. Compared to the case without the labyrinth seal structure, the cases with three different types of sealing teeth have been shown to reduce significantly the tip leakage flow by computational simulations. The double-side sealing teeth case reduces the leakage flowrate mleakage/mpassage from 3.4% to 1.3% and increases the efficiency by 1.4%, which is the maximum efficiency improvement of all cases. The sealing structures increase the loss inside the shroud while reducing the momentum mixing between shroud leakage flow and mainstream. Therefore, the circumferential distribution of leakage velocity is changed, as well as the distribution of high-loss zones at turbine outlet. Furthermore, the leakage-vortex loss, which is associated with the blockage effect of sealing structure to the tip leakage flow, gains more improvement than the passage-vortex at the rotor outlet section in double-side seal case. In addition, it has also been found that with a larger gap at tip, the double-side seal has better effects of reducing the leakage flow and improving the aerodynamic performance in the transonic turbine stage.
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Toebben, Dennis, Piotr Luczynski, Manfred Wirsum, Wolfgang F. D. Mohr, and Klaus Helbig. "Investigation of Steam Turbine Warm-Keeping by Use of Air." Journal of Engineering for Gas Turbines and Power 141, no. 11 (September 16, 2019). http://dx.doi.org/10.1115/1.4044363.
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AbstractThe changing energy landscape leads to a rising demand of more flexible power generation. A system for steam turbine (ST) warm-keeping provides the ability to shutdown conventional power plants during periods with a high share of renewable power. Simultaneously, these power plants are ready for grid stabilization on demand without an excessive consumption of lifetime during the start-up. One technical solution to keep a ST warm is the use of hot air, which is passed through the turbine. In addition, the air supply prevents corrosion during standstill and also enables the prewarming after maintenance or long outages. This paper investigates the warm-keeping process of an intermediate pressure (IP) ST (double-shell configuration) through the use of dynamic numerical finite element (FE) simulations. As a representative test case, warm-keeping calculations during a weekend shutdown (60 h) are conducted to investigate the temperatures, their distribution, and gradients within the rotor and the casing. For this purpose, an improved numerical calculation model is developed. This detailed three-dimensional FE model (including blades and vanes) uses heat transfer correlations conceived for warm-keeping with low air mass flows in gear mode operation. These analytical correlations take heat radiation, convection, and contact heat transfer at the blade roots into account. The thermal boundary conditions (BCs) at the outer walls of the rotor and casing are determined by use of experimental natural cool-down data. The calculation model is finally compared and verified with this dataset. The results offer valuable information about the thermal condition of the ST for a subsequent start-up procedure. The warm-keeping operation with air is able to preserve hot start conditions for any time period. Most of the heat is transferred close to the steam inlet of the turbine, which is caused by similar flow directions of air and steam. Thus, temperatures in the last stages and in the casing remain well below material limits. This allows higher temperatures at the first blade groove of the turbine, which is highly loaded during a turbine startup and thus crucial to the lifetime.
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Jeong, Jin Young, Woobin Kim, Jae Su Kwak, and Jung Shin Park. "Heat Transfer Coefficient and Film Cooling Effectiveness on the Partial Cavity Tip of a Gas Turbine Blade." Journal of Turbomachinery 141, no. 7 (February 22, 2019). http://dx.doi.org/10.1115/1.4042647.
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Leakage flow between the rotating turbine blade tip and the fixed casing causes high heat loads and thermal stress on the tip and near the tip region. For this study, new squealer tips called partial cavity tips, which combine the advantages of plane and squealer tips, were suggested, and the effects of the cavity shape on the tip heat transfer coefficient and film cooling effectiveness were investigated experimentally in a low-speed linear cascade. The suggested blade tips had a flat surface near the leading edge and a squealer cavity from the mid-chord to trailing edge region to achieve the advantages of both blade tip types. The heat transfer coefficient was measured via the 1-D transient heat transfer technique using an IR camera, and the film cooling effectiveness was obtained via the pressure-sensitive paint (PSP) technique. Results showed that the heat transfer coefficient and film cooling effectiveness on the partial cavity tips strongly depended on the cavity shape. Near the leading edge, the heat transfer coefficients for the partial cavity tip cases were lower than that for the squealer tip case. However, the heat transfer coefficient on the cavity surface was higher for the partial cavity tip cases. The D10 tip showed a similar distribution of film cooling effectiveness to that of the plane (PLN) tip near the leading edge and the double side squealer (DSS) tip near the mid-chord region. However, the overall average film cooling effectiveness of the DSS tip was higher than that of the D10 tip.
Dissertations / Theses on the topic "Double casing turbine"
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Trávníček, Tomáš. "Parní turbína pro solární elektrárnu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231806.
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The aim of the master’s thesis is a design of double casing condensing steam turbine with gearbox, reheat and with power output 110 MW for solar power station. The steam turbine has an axial output to the air cooled condenser. The design of the turbine is developed on the basis of concept of Doosan Skoda Power company. It is the main reason this turbine has the impulse blading. There are heat calculation and calculation of heat balance diagram in the first part of the thesis. The system of regeneration consist of three Low Pressure Feedwater Heaters (L.P. FWH), deaerator, and two High Pressure Feedwater Heaters (H.P. FWH). The next part of the thesis is focused on a flow path section of turbine. There is a selection of profile of turbine blades at this part, too. The basic design and strength calculation are available only for high-speed high pressure (HP) part of turbine, as an assignment of the thesis says. There is heat balance diagram for 75 % of nominal power output at the end of thesis. The drawing of longitudinal section of HP part of turbine is the main appendix of this thesis.
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Adámek, Tomáš. "Dvoutělesová kondenzační parní turbina." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230759.
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This thesis is focused on calculation of double casing condensing steam turbine with capacity 200 MW for petrochemical industry´s consumptions. Engine is projected for gas-steam cycle. It has one controlled extraction points placed between two bodies, two uncontrolled extraction points and axial output to air-cooling condenser. Balance scheme was made for 100% operation. Detail design is made only for ST/NT casing and it includes calculation of flowing part, selection of blade´s profile and its stress control. Rotor is checked for critical speed, safety rigid coupling is calculated and according to reaction forces journal bearing are designed. In the end regulation of turbo-set is discussed more precisely and there are calculation of temperature and pressure in uncontrolled extraction points during 80% and 60% operation. Thesis was written out according to Doosan Skoda Power´s instruction and with their cooperation.
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Třináctý, Jan. "Parní turbína pro fosilní elektrárnu - ST NT díl." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231808.
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This thesis describes the design of a condensing steam turbine with reheating for fossil power plant. The turbine is a double parts. The first casing is formed by a simple HP casing. The second casing is combined MP-LP casing with axial outlet of steam into the water-cooled condenser. Feedwater regeneration system consists of two high-pressure heaters, the four low-pressure heaters and feed tank. In thesis is includes the calculation of heat balance and the draft of flow channel of HP and MP-LP casing. Next is a detailed calculation of MP-LP casing with includes calculation of flowing part, selection of blade´s profiles and its stress control. Rotor MP-LP casing is checked for torsion and computed size of the critical speed. Clutch is ispected by security check and draft radial bearings. Stress control casing is carried out according to the theory of thick shells. Work includes flow scheme for 100% and 75% performance. In the end is comparing the efficiency of the individual casing of the turbine with the work 3b together with the specific heat consumption. Work includes a longitudinal section of the MP-LP casing. This thesis has been developed in cooperation Škoda Power, Doosan.
Conference papers on the topic "Double casing turbine"
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de Ojeda, W., R. D. Flack, and S. M. Miner. "Pressure Distributions in a Single and Two Versions of a Double Volute of a Centrifugal Pump." In ASME 1992 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/92-gt-020.
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Pressure measurements were recorded around the impeller and along the casing wall of a centrifugal pump, 0.60 (1583 US units) specific speed, assembled with a single volute/single discharge, and two versions of a double volute/single discharge. The latter comprised a splitter positioned in the second half of the discharge (i) midway between the impeller and casing, and (ii) along a spiral symmetric to the first–half casing section. The objective of such double volute casings is to reduce forces on the impeller and thus provide longer lives. Flow rates tested ranged from 20% to 105% of design. A repeated pattern consisted of pressure increasing from the first cutwater to the splitter leading edge at which the pressure drops and thereafter increases to the discharge. This pattern was noted at all flow rates with the symmetric volute geometry and only at flow rates higher than 60% for the centered splitter. By integration of the pressures static forces were found. Time averaged static forces ranged from 6.2 N at design to 33.0 N at 20% flow for the single volute. Both double volute configurations showed considerable thrust reduction throughout but for a few exceptions. Reductions ranged from 26% at 30% flow to 62% at 90% flow for the center splitter, and from 52% reduction at 20% flow to 72% at 80% flow for the symmetric splitter. For comparison of performance of the different configurations, at flow rates above 85% of design the head was 8% and 9% less for the double volutes than for the single volutes. At flows below 40% of design the head was 3% and 4% higher for the double volutes than for the single volute.
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Tanaka, Yoshinori, Hiroharu Ohyama, Naoto Tochitani, and Tamiaki Nakazawa. "Development and Operating Experience of a Two-Casing 600MW Ultra-Super-Critical Steam Turbine." In ASME 2005 Power Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pwr2005-50344.
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600MW class steam turbines are typically manufactured in three casing configurations with two low-pressure casings. Mitsubishi Heavy Industries (MHI) has developed and manufactured a 600MW two-casing Ultra Super Critical turbine for the Hirono No.5, Tokyo Electric Power Co. in Japan, which comprises one combined high- and intermediate-pressure casing and one double-flow low-pressure casing. This unit started the commercial operation in July 2004. Two-casing design simplifies construction and maintenance requirements and saves capital cost of the plant. This compact design was realized mainly due to the development of 3000 rpm 48 inch steel low-pressure end blades, the longest steel blade in the industries for 3000 rpm machines. In addition, a highly efficient and compact design in achieving 600°C steam condition was realized by employing a combined high- and intermediate-pressure frame. This paper addresses the design features of the 600MW two-casing USC turbine, operating condition of the Hirono No.5 and the results of the verification tests performed.
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Brinkmann, Jürgen, and Peter Dietrich. "Computer-Assisted Manufacturing of a Low Thermal Stress Gasturbine Inner Casing." In ASME 1991 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/91-gt-176.
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This technical paper describes the computer-assisted manufacturing of a newly developed gas turbine inner casing designed by Siemens/KWU for hot gas temperatures up to 1350 °C. After explaining the most important design features, double wall casing with intensive impingement cooling, and details on the special materials involved, the manufacturing sequence and requisite special manufacturing techniques are described. The significant advantages and benefits of a CAD/CAM system tailored to the respective technique employed for this key aerodynamically-optimized item of a stationary gas turbine are elucidated in light of economic concerns and quality requirements and conditions imposed. In conclusion, the transferability of the design principle described in this paper and its implementation in future-oriented developments in fabrication techniques employed in the manufacture of hot-gas-path casings at even higher temperatures are discussed.
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Rockel, David, Stefan Weihard, Andreas Hachmann, Andreas Hupfer, and Hans-Peter Kau. "Numerical Investigation of an Additively Manufactured Compressor Casing: The Effect of Auxetic Structures on the Tip Clearances." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95736.
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A new approach for a compressor casing design has been developed using new design possibilities offered by additive manufacturing technologies. Tip clearance behaviour is a serious problem in compressor design leading to increased aerodynamic losses and limiting the operating range of a compressor through a decrease in surge margin. Efforts are necessary to minimise the tip clearance in the load cycle of an engine. The approach presented in this work uses auxetic structures in a double-walled compressor casing with the aim to force the radial expansion behaviour of the inner casing wall in order to adapt the casing to the rotor. The studies of the casing and the calculations of the transient rotor displacement are carried out by using coupled-temperature-displacement calculations using commercial FEM-tools. Elements which influence the radial expansion of the casing are identified with the aim of generating a modular system for future compressor casing developments. So the casing elements are adaptable to the radial expansion of a certain rotor. An improved tip clearance behaviour in relevant operating points is achieved. In the latter part of the paper, practical design considerations are made as the auxetic structures are integrated into the CAD model of an existing compressor casing. Design challenges are also briefly discussed. This paper presents a new potential application of additive manufacturing technologies in future aero engine design. The focus of this paper is on the practical implementation of the new design freedom using the example of a compressor casing. The advantages for the overall engine performance as well as identified problems are also discussed qualitatively.
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Chana, K. S., and B. Haller. "Novel Turbine Rotor Shroud Film-Cooling Design and Validation: Part 1." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-60242.
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This paper is part one of a two part paper which considers a shroud film-cooling system designed using a two-dimensional approach. Heat transfer to rotor-casings has reached levels that are causing in-service difficulties to be experienced. Future designs are likely to need to employ film-cooling of some form. There is currently very little information available for film-cooling on shroudless turbine rotor-casing liners. Heat transfer literature on uncooled configurations is not extensive and in particular, spatially-detailed, time-accurate data are rare. This paper describes the aero-thermodynamic design and validation of a rotor casing film-cooling system for a transonic, high-pressure shroudless turbine stage. The design was carried out using a boundary layer code with the film-cooling hole geometry representative of an engine configuration and, has been subjected to mechanical constraints similar to those for an engine component. The design consists of two double rows of cooling holes and two ‘cooling-hole’ shape configurations, cylindrical and fan shaped. The design was tested in the QinetiQ short duration turbine test facility (TTF). Measurements taken include casing heat transfer using thin film gauges and stage exit total pressure, Mach number and flow angle using a three-hole pressure probe. Results showed that while the cooling produced a reduction in the heat transfer rate close to the injection point, the film was stripped off the casing and entrained in nozzle guide vane secondary and rotor overtip flow, where it was transported spanwise towards the hub in the rotor passage. Using the results obtained from this deign a second cooling design was carried out, using a three-dimensional approach this gave significantly better cooling performance. The thee-dimensional design and validation is reported in GT2009-60246 as part 2 of this paper.
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Wang, Yabo, Yanping Song, Jianyang Yu, and Fu Chen. "Effect of the Double-Slot Injection on the Leakage Flow Control in a Honeycomb-Tip Turbine Cascade." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90589.
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Abstract The effect of five arrangements of the double-slot injections on the leakage flow control is studied in a honeycomb-tip turbine cascade numerically. The honeycomb tip is covered with 67 intact honeycomb cavities, since the uneven tip is wearable and the cavity vortex could realize the aerodynamic sealing for the leakage flow. Then in the present study, a pair of injection slots is arranged blow each cavity, aiming to enhance the leakage flow suppression by modifying the cavity vortex. According to the orientation of the two slots, five designs of the double-slot injections are proposed. In detail, the two slots are opposite to each other or keep tangential to the original cavity vortex roughly. The three dimensional calculations were completed by using Reynolds-averaged Navier-Stokes (RANS) method and the k-ω turbulence model in the commercial software ANSYS CFX. The estimation of these tip designs is mainly according to the tip leakage mass flow rate and the total pressure loss. Firstly, the injection structures induced by the slots can be divided into X- and T-types inside the cavity. The results show that the T-type structure is more effective in reducing the tip leakage mass flow rate, with the maximum reduction up to 48.2%. Then the effect on the flow field inside the gap and the secondary flow in the upper passage is analyzed. Compared with the flat tip, the span-wise position of the tip leakage vortex core drops within the cascade and the range of the affected loss region expands. At the cascade exit, the tip leakage vortex moves toward the passage vortex near the casing, while the latter’s core rises. The position changes of the secondary vortices eventually determine the total pressure loss contour downstream the cascade. Finally, the injection total pressure and the upper casing motion are investigated. Interestingly, the injection intensity (mass flow rate) increases with the injection total pressure but this value decreases as the casing speed increases. The tip leakage mass flow rate decreases linearly as increasing the injection total pressure or the casing speed. Yet the averaged total pressure loss downstream the cascade increases with the injection total pressure but appears a nonlinear distribution against the casing speed.
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Rolfes, Matthias, Martin Lange, and Konrad Vogeler. "Experimental Investigation of Circumferential Groove Casing Treatments for Large Tip Clearances in a Low Speed Axial Research Compressor." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-42646.
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In high pressure compressors large tip clearances can occur in the rear stages especially during transient operation. This can lead to a reduced operating range and performance of the compressor. One simple means to reduce the negative effects of a rotor tip clearance increase can be circumferential groove casing treatments. Their ability to improve the operating range of a compressor is well-known for several decades. In this paper, an experimental study to investigate the influence of three different circumferential groove casing treatments on a low speed axial research compressor with very large rotor tip clearances (5% of annulus height) is presented. Two single-groove and one double-groove casing treatments have been tested. The grooves are positioned from 31% to 69% axial chord. The compressor characteristics of the smooth wall and the three groove configurations are discussed as well as selected five-hole probe measurements of the flow field downstream the rotor. It can be shown that all grooves are able to improve the operating range of the compressor. Furthermore, an improvement of efficiency due to the casing grooves can also be observed in certain operating points.
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Bruna, Dario, and Mark G. Turner. "A Rothalpy Analysis for the Isothermal Boundary Condition at Casing Applied to the Rotor 37 Transonic Axial Flow Compressor." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94595.
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CFD simulations have been set-up with an isothermal boundary condition at the casing for running the NASA Rotor 37 axial compressor. The casing temperature was set to the inlet total temperature. The comparison to data was much improved for the efficiency for the 100% speed line relative to the adiabatic simulations. The efficiency difference between the isothermal and adiabatic solutions is about 1%, with the isothermal calculation matching the low flow test condition. The profiles of total temperature with the isothermal boundary condition matched the data near the casing without any overshoot, typical of most compressor calculations. Also the efficiency profile had a similar improvement in matching the data because of its relationship to temperature. A similar comparison between isothermal and adiabatic cases has been carried out for the same geometry with double the design clearance. The working range based on the steady CFD calculations is about half that of the design clearance case which is felt to be realistic. Moreover a detailed analysis based on conservation of Rothalpy has been made and applied to the rotor. Mass averaged Rothalpy is not conserved due to a frictional power term associated with the stationary case as well as heat transfer. The effects of these terms show the extent of the heat transfer is between 10–20% of span away from the casing. The heat transfer effect calculated with the isothermal boundary condition simulation is thought to be real, and accounting for it matches data better than using an adiabatic assumption. However, the real rig would probably not be isothermal at the casing and may require more complex simulations such as a conjugate heat transfer approach.
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van Paridon, Andrew, Andrew Dann, Peter Ireland, and Marko Bacic. "Design and Development of a Full-Scale Generic Transient Heat Transfer Facility (THTF) for Air System Validation." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-42391.
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This paper describes the design and development of a major new facility capable of reproducing flow conditions for large civil aero engine turbine and compressor segment cavities. The facility reproduces in 3-D, typical secondary air system cruise temperatures, pressures and mass flows. The facility allows better understanding of the circumferential heat transfer effects of air system flows on turbine and compressor casings, as these have a significant influence on both steady-state and transient blade tip clearance behavior. Different air system architectural solutions are considered and 1-D transient air system modelling is used to design architecture to ensure that they meet tight performance requirements in terms of allowable pressure and temperature ripples when subject to fast switching of flows. An explanation of the design of the double-skin pressure vessel using 2-D axisymmetric thermo-mechanical analysis to understand the life-limiting features of the design is discussed. Finally we conclude the paper with some experimental results from rig commissioning and the use of these results in the determination of engine casing transients is discussed.
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Kagawa, Shusaku, Takaki Sakurai, Hiroyuki Kaneko, and Hidenobu Okamoto. "Hydraulic Design and Performance Adjustment of a Reverse Running Pump Turbine Based on a Double Suction Pump." In ASME/JSME/KSME 2015 Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ajkfluids2015-09186.
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This paper described a reverse running double suction centrifugal pump turbine, which was newly designed and developed in order to adopt at a high fixed rotational speed 2980 [min−1] with high head H=245.6 [m]. New turbine model was developed by using CFD and its performance was validated by model test. There were a few studies about a reverse running pump turbine. However, a method of “Q-H performance adjustment” for the pump turbine is not clear. In order to reveal a method of Q-H performance adjustment of a turbine, CFD simulation and model test was carried out. The model test results showed that the performance of new turbine model fully satisfied Q-H requirement. And the results of steady CFD simulation were in good agreements with the model test results. Two possible methods to adjust the Q-H performance curve of a reverse running double suction centrifugal pump turbine were confirmed by model tests and CFD. The first method was modifying a throat sectional area of inlet spiral casing by cutting off a casing tongue. The model test result showed that this method moves the Q-H performance curve of turbine from high head to lower head at a constant capacity with very small efficiency drop at rated operating point. The result of CFD showed that, the Q-H performance change was obtained by the change in absolute tangential velocity at the runner inlet, which represents the inlet angular momentum, by the modification of throat sectional area. The second method was adjusting the runner outlet velocity triangle by modifying the runner blade trailing edge profile by under-filing or over-filing. The model test result proved that, the above modification of runner blade trailing edge profile is effective to control the Q-H performance curve of a reverse running pump turbine.