Improving the Efficiency of the Trent 500 HP Turbine Using Non-Axisymmetric End Walls: Part 1 — Turbine Design

2001 ◽  
Author(s):  
G. Brennan ◽  
N. W. Harvey ◽  
M. G. Rose ◽  
N. Fomison ◽  
M. D. Taylor
Keyword(s):  
Large Scale ◽  
Design System ◽  
Linear Cascade ◽  
Low Speed ◽  
Significant Potential ◽  
Definition Of ◽  
Turbine Design ◽  
Shrouded Rotor ◽  
End Wall ◽  
Turbine Model

This paper describes the redesign of the HP turbine of the Rolls-Royce Trent 500 engine, making use of non-axisymmetric end walls. The original, datum turbine used conventional axisymmetric end walls, while the vane and (shrouded) rotor aerofoil profiles were nominally the same for the two designs. Previous research on the large scale, low speed linear cascade at Durham University, see Hartland et al [1], had already demonstrated significant potential for reducing turbine secondary losses using non-axisymmetric end walls - by about one third. This paper shows how a methodology was derived from the results of this research and applied to the design of the single stage Trent 500 HP turbine (model rig). In particular the application of a new linear design system for the parametric definition of these end wall shapes, described in Harvey et al [2], is discussed in detail.

Improving the Efficiency of the Trent 500-HP Turbine Using Nonaxisymmetric End Walls—Part I: Turbine Design

2003 ◽  
Vol 125 (3) ◽  
pp. 497-504 ◽  
Author(s):  
G. Brennan ◽  
N. W. Harvey ◽  
M. G. Rose ◽  
N. Fomison ◽  
M. D. Taylor
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Design System ◽  
Turbine Cascade ◽  
Linear Cascade ◽  
Definition Of ◽  
Turbine Design ◽  
Shrouded Rotor ◽  
End Wall ◽  
Turbine Model

This paper describes the redesign of the HP turbine of the Rolls-Royce Trent 500 engine, making use of nonaxisymmetric end walls. The original, datum turbine used conventional axisymmetric end walls, while the vane and (shrouded) rotor aerofoil profiles were nominally the same for the two designs. Previous research on the large-scale, low-speed linear cascade at Durham University (see Hartland et al., 1998, “Non-Axisymmetric End Wall Profiling in a Turbine Cascade,” ASME 98–GT-525), had already demonstrated significant potential for reducing turbine secondary losses using nonaxisymmetric end walls-by about one third. This paper shows how a methodology was derived from the results of this research and applied to the design of the single-stage Trent 500-HP turbine (model rig). In particular, the application of a new linear design system for the parametric definition of these end wall shapes (described in Harvey et al., 1999, “Non-Axisymmetric Turbine End Wall Design: Part I Three-Dimensional Linear Design System,” ASME 99–GT-337) is discussed in detail.

scholarly journals Use of a Tracer Gas Technique to Study Mixing in a Low Speed Turbine

1981 ◽  
Author(s):  
J. D. Denton ◽  
S. Usui
Keyword(s):  
Boundary Layers ◽  
Large Scale ◽  
Small Concentration ◽  
Flame Ionization Detector ◽  
Ionization Detector ◽  
Tracer Gas ◽  
Low Speed ◽  
Flame Ionization ◽  
Air Turbine ◽  
End Wall

A method of using a flame ionization detector to study the movement of air containing a small concentration of ethylene is described. Ethylene is chosen because it has almost the same density as air so buoyancy effects are negligible. The technique is applied to flow in a bent duct and in a low speed air turbine. In both cases large scale migrations of the end wall boundary layers onto the suction surfaces are observed. However, in the turbine the span wise movement and mixing of the flow at mid-span is remarkably small.

Improving the Efficiency of the Trent 500 HP Turbine Using Non-Axisymmetric End Walls: Part II — Experimental Validation

2001 ◽  
Author(s):  
M. G. Rose ◽  
N. W. Harvey ◽  
P. Seaman ◽  
D. A. Newman ◽  
D. McManus
Keyword(s):  
Design Methodology ◽  
Experimental Validation ◽  
Axial Flow ◽  
Cfd Analysis ◽  
Hot Wire ◽  
Flow Conditions ◽  
Linear Cascade ◽  
Turbine Efficiency ◽  
End Wall ◽  
Turbine Model

Part I of this paper described how the HP turbine model rig of the Rolls-Royce Trent 500 was redesigned by applying non-axisymmetric end walls to both the vane and blade passages, whilst leaving the turbine operating point and overall flow conditions unaltered. This paper describes the results obtained from testing of the model rig and compares them with those obtained for the datum design (with conventional axisymmetric end walls). Measured improvements in the turbine efficiency are shown to be in line with those expected from the previous linear cascade research at Durham University, see Harvey et al. [1] and Hartland et al. [2]. These improvements are observed at both design and off-design conditions. Hot wire traverses taken at the exit of the rotor show, unexpectedly, that the end wall profiling has caused changes across the whole of the turbine flow field. This result is discussed making reference to a preliminary 3-D CFD analysis. It is concluded that the design methodology described in part I of this paper has been validated, and that non-axisymmetric end wall profiling is now a major new tool for the reduction of secondary loss in turbines (and potentially all axial flow turbomachinery). Further work, though, is needed to fully understand the stage (and multistage) effects of end wall profiling.

Optimization of Non-Axisymmetric End Wall Contours for the Rotor of a Low Speed, 1 1/2 Stage Research Turbine With Unshrouded Blades

2012 ◽  
Author(s):  
Jonathan Bergh ◽  
Glen Snedden ◽  
Christiaan Meyer
Keyword(s):  
Flow Field ◽  
Secondary Flow ◽  
Recent Work ◽  
Specific Design ◽  
Established Method ◽  
Linear Cascade ◽  
Low Speed ◽  
End Wall

Non-axisymmetric end wall contouring has become an established method for the reduction of the losses associated with secondary flow. To date, the majority of designs have been produced by the aeroengine manufacturing community and as a result access to specific design and methodological details is often limited [1]. In contrast, whilst the details of non-embargoed work are more freely available, much of this work has been carried out in simplified environments, with the most common of these being 2-dimensional, linear cascades, and therefore do not include a number of features which are present in the flow field of a real turbine [2]. Recent work by Snedden et al [3] involved the introduction of “generic”, non-axisymmetric end wall contours, originally designed for a linear cascade (the so-called Durham cascade), into the rotor row of a low speed, 1 1/2 stage research turbine. While an increase in rotor performance was noted, a detailed inspection of the flow results suggested that even greater improvements could be obtained through the design of custom end walls for the turbine. This investigation therefore covers the design of custom non-axisymmetric end wall contours for the rotor row of an annular turbine rig with unshrouded blades (the same rig as that used by Snedden), using a modified version of an end wall design routine originally developed for the production of non-axisymmetric end walls for a linear cascade environment.

Design and Analysis of Ultra-Low Speed Movement Equipment System

2011 ◽  
Vol 130-134 ◽  
pp. 1475-1479
Author(s):  
Feng Yan Dai ◽  
Wen Gang Ji ◽  
Jian Shu Cao
Keyword(s):  
Crystal Growth ◽  
Large Scale ◽  
Control Method ◽  
Laser Crystal ◽  
Spare Parts ◽  
Design System ◽  
Growth Speed ◽  
Low Speed ◽  
Crystal Growth Mechanism ◽  
Lifting System

Czochralski lifting device is the key equipment for crystal growth. Due to laser crystal growth mechanism could decide its slow growth speed, so Lifting device is required to operate under the ultra-low speed situation chronically. According to shock, shake, fraction and crawl of movement system affected speed stability, the paper carries out a nobel design to laser Czochralski lifting system through alternated servo technology and its precision is analyzed comprenshensively. The long-term experimental data showed by using changed plus PID control method that the system has high precision and better reliability and it is suitable to grow large-size laser crystal. Meanwhile, the design system makes use of common spare parts and can meet the requirements for large scale industrialization.

scholarly journals Nonaxisymmetric Turbine End Wall Design: Part II—Experimental Validation

1999 ◽  
Vol 122 (2) ◽  
pp. 286-293 ◽  
Author(s):  
J. C. Hartland ◽  
D. G. Gregory-Smith ◽  
N. W. Harvey ◽  
M. G. Rose
Keyword(s):  
Secondary Flow ◽  
Three Dimensional ◽  
Design System ◽  
Flow Angle ◽  
Linear Cascade ◽  
Pressure Distributions ◽  
Turbine Performance ◽  
Passage Vortex ◽  
Blade Row ◽  
End Wall

The Durham Linear Cascade has been redesigned with the nonaxisymmetric profiled end wall described in the first part of this paper, with the aim of reducing the effects of secondary flow. The design intent was to reduce the passage vortex strength and to produce a more uniform exit flow angle profile in the radial direction with less overturning at the wall. The new end wall has been tested in the linear cascade and a comprehensive set of measurements taken. These include traverses of the flow field at a number of axial planes and surface static pressure distributions on the end wall. Detailed comparisons have been made with the CFD design predictions, and also for the results with a planar end wall. In this way an improved understanding of the effects of end wall profiling has been obtained. The experimental results generally agree with the design predictions, showing a reduction in the strength of the secondary flow at the exit and a more uniform flow angle profile. In a turbine stage these effects would be expected to improve the performance of any downstream blade row. There is also a reduction in the overall loss, which was not given by the CFD design predictions. Areas where there are discrepancies between the CFD calculations and measurement are likely to be due to the turbulence model used. Conclusions for how the three-dimensional linear design system should be used to define end wall geometries for improved turbine performance are presented. [S0889-504X(00)01002-3]

Endwall Profiling With Tip Clearance Flows

2012 ◽  
Author(s):  
Michael Hilfer ◽  
Grant Ingram ◽  
Simon Hogg
Keyword(s):  
Aspect Ratio ◽  
Design Process ◽  
Experimental Validation ◽  
Tip Clearance ◽  
Design System ◽  
Tip Clearance Flow ◽  
Linear Cascade ◽  
Low Speed ◽  
Clearance Flow

This paper describes the design of a non-axisymmetric profiled endwall with tip clearance flow. Previous designs have assumed that the interaction between the tip clearance flow and the endwall has been negligible and this paper allows this assumption to be tested. A profiled endwall was designed, built and tested in a low speed linear cascade. The design was conducted using the Durham endwall design system and this paper provides details of the first experimental validation of this system. Overall the design system was found to perform successfully. Many other researchers have conducted endwall design, test and build exercises and the key advance here was to examine the effect of profiled endwalls on tip clearance flow. To this end a tip clearance was added to both the CFD and the cascade during the design process. The results show that even with an aspect ratio of two the endwall produces noticeable changes on the tip clearance flow. This does not however necessarily prevent a successful profiled endwall from being implemented in the cascade.

scholarly journals Non-Axisymmetric Turbine End Wall Design: Part II — Experimental Validation

1999 ◽  
Author(s):  
J. C. Hartland ◽  
D. G. Gregory-Smith ◽  
N. W. Harvey ◽  
M. G. Rose
Keyword(s):  
Secondary Flow ◽  
Three Dimensional ◽  
Design System ◽  
Flow Angle ◽  
Linear Cascade ◽  
Pressure Distributions ◽  
Turbine Performance ◽  
Passage Vortex ◽  
Blade Row ◽  
End Wall

The Durham Linear Cascade has been redesigned with the non-axisymmetric profiled end wall described in the first part of this paper, with the aim of reducing the effects of secondary flow. The design intent was to reduce the passage vortex strength and to produce a more uniform exit flow angle profile in the radial direction with less over turning at the wall. The new end wall has been tested in the linear cascade and a comprehensive set of measurements taken. These include traverses of the flow field at a number of axial planes and surface static pressure distributions on the end wall. Detailed comparisons have been made with the CFD design predictions, and also for the results with a planar end wall. In this way an improved understanding of the effects of end wall profiling has been obtained. The experimental results generally agree with the design predictions, showing a reduction in the strength of the secondary flow at the exit and a more uniform flow angle profile. In a turbine stage these effects would be expected to improve the performance of any downstream blade row. There is also a reduction in the overall loss, which was not given by the CFD design predictions. Areas where there are discrepancies between the CFD calculations and measurement are likely to be due to the turbulence model used. Conclusions for how the three-dimensional linear design system should be used to define end wall geometries for improved turbine performance are presented.

CONCEPT OF THE IMPROVEMENT OF A KEY PUBLIC SPACE (USING THE EXAMPLE OF «ALLEY OF ARCHITECTS», VORONEZH)

2020 ◽  
pp. 97-109
Author(s):  
С. Л. Подвальный ◽  
О. А. Сотникова ◽  
Я. А. Золотухина
Keyword(s):  
Urban Environment ◽  
Public Space ◽  
Large Scale ◽  
Economic Value ◽  
Ecological Condition ◽  
Territory Design ◽  
Definition Of ◽  
The City ◽  
Modern Technologies ◽  
Intensive Growth

Постановка задачи. В настоящее время формирование современной комфортной городской среды приобретает особое социально-экономическое значение и выдвигается в число приоритетных государственных масштабных программ. В связи с этим необходимо разработать концепцию благоустройства ключевого общественного пространства, а именно: определить основные и сопутствующие функции данной территории, создать эскизное предложение проекта благоустройства с учетом всех необходимых норм и стандартов, внедрить современные технологии. Результаты. Выполнен эскизный дизайн-проект «Аллеи архитекторов» по ул. Орджоникидзе г. Воронеж, включающий в себя основные элементы по зонированию территории, проектированию акцентных объектов и внедрению инновационных технологий «умного города», позволяющих повысить уровень комфорта горожан. Выводы. Благоустройство населенных мест приобретает особое значение в условиях дискомфорта среды. С выполнением комплекса мероприятий, направленных на благоустройство, и с внедрением современных технологий значительно улучшается экологическое состояние, внешний облик города. Оздоровление и модернизация среды, которая окружает человека в городе, благотворно влияет на психофизическое состояние, что особенно важно в период интенсивного роста городов. Statement of the problem. Currently the formation of the modern comfortable urban environment is gaining a special social and economic value and moving forward in the priorities of state large-scale programs. The purpose of development of the concept of improvement of public space is definition of the main and accompanying functions of this territory, design of the outline offer of the project of improvement considering all necessary norms and standards and implementation of modern technologies. Results. The conceptual project of “Alley of Architects” includes the basic elements of territory zoning, design of accent objects and implementation of technologies of a “smart-city”. These elements allow one to increase the level of comfort of inhabitants. Conclusions. Improvement of the inhabited places is of particular importance in the conditions of discomfort of the environment. Carrying out a complex of the actions directed to gardening and improvement, introducing modern technologies, the ecological condition, the physical appearance of the city considerably improves. Improvement and modernization of the environment which surrounds the person in the city influences a psychophysical state well that especially important during intensive growth of the cities.

Bottlenecks in the Implementation of On-Site Wastewater Treatment Plants on a Large Scale in The Netherlands

1990 ◽  
Vol 22 (3-4) ◽  
pp. 291-298
Author(s):  
Frits A. Fastenau ◽  
Jaap H. J. M. van der Graaf ◽  
Gerard Martijnse
Keyword(s):  
Wastewater Treatment ◽  
The Netherlands ◽  
Large Scale ◽  
Wastewater Treatment Plants ◽  
Housing Stock ◽  
Research Work ◽  
Field Research ◽  
Domestic Wastewater ◽  
Research Programme ◽  
Definition Of

More than 95 % of the total housing stock in the Netherlands is connected to central sewerage systems and in most cases the wastewater is treated biologically. As connection to central sewerage systems has reached its economic limits, interest in on-site treatment of the domestic wastewater of the remaining premises is increasing. A large scale research programme into on-site wastewater treatment up to population equivalents of 200 persons has therefore been initiated by the Dutch Ministry of Housing, Physical Planning and Environment. Intensive field-research work did establish that the technological features of most on-site biological treatment systems were satisfactory. A large scale implementation of these systems is however obstructed in different extents by problems of an organisational, financial and/or juridical nature and management difficulties. At present research is carried out to identify these bottlenecks and to analyse possible solutions. Some preliminary results are given which involve the following ‘bottlenecks':-legislation: absence of co-ordination and absence of a definition of ‘surface water';-absence of subsidies;-ownership: divisions in task-setting of Municipalities and Waterboards; divisions involved with cost-sharing;-inspection; operational control and maintenance; organisation of management;-discharge permits;-pollution levy;-sludge disposal. Final decisions and practical elaboration of policies towards on-site treatment will have to be formulated in a broad discussion with all the authorities and interest groups involved.

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