GASCAN—An Interactive Code for Thermal Analysis of Gas Turbine Systems

1988 ◽  
Vol 110 (2) ◽  
pp. 201-209 ◽  
Author(s):  
M. A. El-Masri
Keyword(s):  
Gas Turbine ◽  
System Analysis ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
System Optimization ◽  
Interactive System ◽  
Turbine Cooling ◽  
Balance Analysis ◽  
Three Dimensional Models ◽  
Turbine Design

A general, dimensionless formulation of the thermodynamic, heat transfer, and fluid-dynamic processes in a cooled gas turbine is used to construct a compact, flexible, interactive system-analysis program. A variety of multishaft systems using surface or evaporative intercoolers, surface recuperators, or rotary regenerators, and incorporating gas turbine reheat combustors, can be analyzed. Different types of turbine cooling methods at various levels of technology parameters, including thermal barrier coatings, may be represented. The system configuration is flexible, allowing the number of turbine stages, shaft/spool arrangement, number and selection of coolant bleed points, and coolant routing scheme to be varied at will. Interactive iterations between system thermodynamic performance and simplified quasi-three-dimensional models of the turbine stages allow exploration of realistic turbine-design opportunities within the system/thermodynamic parameter space. The code performs exergy-balance analysis to break down and trace system inefficiencies to their source components and source processes within the components, thereby providing insight into the interactions between the components and the system optimization tradeoffs.

scholarly journals Computational Fluid Dynamic Analysis of a Vibrating Turbine Blade

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Osama N. Alshroof ◽  
Gareth L. Forbes ◽  
Nader Sawalhi ◽  
Robert B. Randall ◽  
Guan H. Yeoh
Keyword(s):  
Gas Turbine ◽  
Turbine Blade ◽  
Moving Boundary ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Commercial Software ◽  
Computational Fluid Dynamic Analysis ◽  
Current State ◽  
Blade Tip ◽  
The One

This study presents the numerical fluid-structure interaction (FSI) modelling of a vibrating turbine blade using the commercial software ANSYS-12.1. The study has two major aims: (i) discussion of the current state of the art of modelling FSI in gas turbine engines and (ii) development of a “tuned” one-way FSI model of a vibrating turbine blade to investigate the correlation between the pressure at the turbine casing surface and the vibrating blade motion. Firstly, the feasibility of the complete FSI coupled two-way, three-dimensional modelling of a turbine blade undergoing vibration using current commercial software is discussed. Various modelling simplifications, which reduce the full coupling between the fluid and structural domains, are then presented. The one-way FSI model of the vibrating turbine blade is introduced, which has the computational efficiency of a moving boundary CFD model. This one-way FSI model includes the corrected motion of the vibrating turbine blade under given engine flow conditions. This one-way FSI model is used to interrogate the pressure around a vibrating gas turbine blade. The results obtained show that the pressure distribution at the casing surface does not differ significantly, in its general form, from the pressure at the vibrating rotor blade tip.

Integration of knowledge-based and generative systems for building characterization and prediction

2010 ◽  
Vol 24 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Ajla Aksamija ◽  
Kui Yue ◽  
Hyunjoo Kim ◽  
Francois Grobler ◽  
Ramesh Krishnamurti
Keyword(s):  
Architectural Design ◽  
Contextual Information ◽  
Three Dimensional ◽  
Knowledge Bases ◽  
Shape Grammar ◽  
Interactive System ◽  
Existing Buildings ◽  
Knowledge Based ◽  
Building Models ◽  
Three Dimensional Models

AbstractThis paper discusses the integration of knowledge bases and shape grammars for the generation of building models, covering interaction, system, and implementation. Knowledge-based and generative systems are combined to construct a method for characterizing existing buildings, in particular, their interior layouts based on exterior features and certain other parameters such as location and real dimensions. The knowledge-based model contains information about spatial use, organization, elements, and contextual information, with the shape grammar principally containing style rules. Buildings are analyzed and layouts are generated through communication and interaction between these two systems. The benefit of using an interactive system is that the complementary properties of the two schemes are employed to strengthen the overall process. Ontologies capture knowledge relating to architectural design principles, building anatomy, structure, and systems. Shape grammar rules embody change through geometric manipulation and transformation. Existing buildings are analyzed using this approach, and three-dimensional models are automatically generated. Two particular building types, the vernacular rowhouse and high-rise apartment building, both from Baltimore, Maryland, are presented to illustrate the process and for comparing the utilized methodologies.

scholarly journals Simulation and Flow Analysis of the Hole Diaphragm Labyrinth Seal at Several Whirl Frequencies

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 379
Author(s):  
Xiang Zhang ◽  
Yinghou Jiao ◽  
Xiuquan Qu ◽  
Guanghe Huo ◽  
Zhiqian Zhao
Keyword(s):  
Gas Turbine ◽  
Reverse Flow ◽  
Fluid Dynamic ◽  
Dynamic Performance ◽  
Flow Analysis ◽  
Labyrinth Seal ◽  
Unusual Phenomenon ◽  
Complex Fluid ◽  
Turbine Design ◽  
Velocity Turbulence

The seal is designed to reduce leakage and improve the efficiency of gas turbine machines, and is an important technology that needs to be studied in gas turbine design. A series of seals were proposed to try to achieve this goal. However, due to the complex fluid dynamic performance of the seal-rotor system, the seal structure can obtain both the best leakage performance and best rotordynamic performance. This paper presents a detailed flow analysis of the hole diaphragm labyrinth seal (HDLS) at several whirl frequencies and several rotation speeds. The pressure drop, velocity, turbulence kinetic energy and leakage performance of the HDLS were discussed by simulations. An interesting exponential–type relationship between rotation speeds and leakage flow at different whirl frequencies was observed by curve fitting technology. A reverse flow rate was proposed to describe such an unusual phenomenon. Such a relationship can be used to further establish the leakage model of the HDLS and other similar seals.

Air Extraction in a Gas Turbine for Integrated Gasification Combined Cycle (IGCC): Experiments and Analysis

1997 ◽  
Vol 119 (1) ◽  
pp. 20-26 ◽  
Author(s):  
J. S. Kapat ◽  
A. K. Agrawal ◽  
T. Yang
Keyword(s):  
Gas Turbine ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Combined Cycle ◽  
Scale Model ◽  
Integrated Gasification Combined Cycle ◽  
Computational Fluid Dynamic Analysis ◽  
Alternate Scheme ◽  
Integrated Gasification ◽  
Flow Experiments

This paper presents an investigation of extracting air from the compressor discharge of a heavy-frame gas turbine. The study aimed to verify results of an approximate analysis: whether extracting air from the turbine wrapper would create unacceptable nonuniformity in the flow field inside the compressor discharge casing. A combined experimental and computational approach was undertaken. Cold flow experiments were conducted in an approximately one-third scale model of a heavy-frame gas turbine; a closely approximated three-dimensional computational fluid dynamic analysis was also performed. This study substantiated the earlier prediction that extracting air from the turbine wrapper would be undesirable, although this method of air extraction is simple to retrofit. Prediffuser inlet is suggested as an alternate location for extracting air. The results show that not only was the problem of flow nonuniformity alleviated with this alternate scheme, but the frictional power loss in the compressor discharge casing was also reduced by a factor of two.

Analysis of the Aerodynamic Losses in a Supersonic Turbine

2017 ◽  
Author(s):  
Jorge Sousa ◽  
Guillermo Paniagua ◽  
Elena Collado-Morata
Keyword(s):  
High Speed ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Design Procedure ◽  
Design Procedures ◽  
Speed Flow ◽  
Viscous Losses ◽  
Inlet Conditions ◽  
Turbine Design ◽  
Turbomachinery Design

The current development of detonation based combustors has triggered the necessity to develop new turbomachinery design procedures to achieve operable and efficient fluid machines. The high-speed flow typically observed at the outlet of a rotating detonation combustors leads to a rather challenging turbine design. The present paper reports the development of a tailored methodology to predict the non-isentropic operation of turbines exposed to supersonic inlet conditions. This one-dimensional design procedure starts by identifying the operable design space, and uses empirical loss models to estimate the main sources of inviscid and viscous losses. The turbine performance is analyzed for different design choices and compared with three dimensional computational fluid dynamic results.

Multicode Prediction of the Influence of the Exhaust System on the Performance of a Turbocharged Engine

2002 ◽  
Vol 124 (3) ◽  
pp. 695-701 ◽  
Author(s):  
G. Chiatti ◽  
O. Chiavola
Keyword(s):  
Gas Flow ◽  
Fluid Dynamic ◽  
Flow Behavior ◽  
Three Dimensional ◽  
Engine Performance ◽  
Exhaust System ◽  
One Dimensional ◽  
Fast Processing ◽  
Dimensional Models ◽  
Three Dimensional Models

A multicode approach, based on the simultaneous use of zero-dimensional, one-dimensional, and three-dimensional models, has been developed and tested, and is here applied to predict the thermodynamic and fluid dynamic phenomena that characterize the unsteady gas flow propagation along the exhaust system of a turbocharged four-cylinder engine. The investigation is carried out by applying each model in a different region of the geometry, allowing to obtain detailed information of the flow behavior in complex elements, such as junctions, avoiding the significant limitations that a one-dimensional scheme always introduces, as well as fast processing typical of one-dimensional and zero-dimensional models, devoted to the analysis of ducts and volumes. The effect of the influence of different configurations of the exhaust system on the engine performance is analyzed.

On the Prediction of Swirling Flowfields Found in Axisymmetric Combustor Geometries

1982 ◽  
Vol 104 (3) ◽  
pp. 378-384 ◽  
Author(s):  
D. L. Rhode ◽  
D. G. Lilley ◽  
D. K. McLaughlin
Keyword(s):  
Gas Turbine ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Boundary Representation ◽  
Reacting Flow ◽  
Gas Turbine Combustor ◽  
Turbine Engine ◽  
Research Activities ◽  
Gradual Expansion ◽  
Neutrally Buoyant

Combustor modeling has reached the stage where the most useful research activities are likely to be on specific sub-problems of the general three-dimensional turbulent reacting flow problem. The present study is concerned with a timely fluid dynamic research task of interest to the combustor modeling community. Numerical computations have been undertaken for a basic two-dimensional axisymmetric flowfield which is similar to that found in a conventional gas turbine combustor. A swirling nonreacting flow enters a larger chamber via a sudden or gradual expansion. The calculation method includes a stairstep boundary representation of the expansion flow, a conventional k-ε turbulence model and realistic accommodation of swirl effects. The results include recirculation zone characterization and predicted mean streamline patterns. In addition, an experimental evaluation using flow visualization of neutrally-buoyant helium-filled soap bubbles is yielding very promising results. Successful outcomes of the work can be incorporated into the more combustion- and hardware-oriented activities of gas turbine engine manufacturers, including incorporating the modeling aspects into already existing comprehensive numerical solution procedures.

Thermal and Fluid Dynamic Analysis of the Gas Turbine Transition Piece

2009 ◽  
Author(s):  
J. Arturo Alfaro Ayala ◽  
Armando Gallegos Mun˜oz ◽  
Alejandro Zaleta Aguilar ◽  
Alfonso Campos Amezcua ◽  
Zdzislaw Mazur
Keyword(s):  
Flow Field ◽  
Dynamic Analysis ◽  
Gas Turbine ◽  
Cooling System ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Peak Temperature ◽  
Three Dimensional Model ◽  
Transition Piece ◽  
The Difference

This paper presents the thermal and fluid dynamic analysis of the gas turbine transition piece, applying the Finite Volume Method (FVM) through the Computational Fluid Dynamics (CFD). The study is carried out to examine the flow field and distribution of temperatures of the combustion gases along the transition piece and exit mouth, getting profiles and contours of velocity and temperature. This study is important to know the paths of flow and distribution of temperatures of the hot streaks through the transition piece, which impact on cooling system in stator and rotor. Also, these flow field and distribution of temperature have an effect in performance and life of the vanes and blades in the first stage of the turbine, principally by the difference of heat load. The study was carried out in a steady state three-dimensional model to avoid the geometric simplifications, using code FLUENT® version 6.3.26 where the k-ε turbulence model was applied and different boundary conditions in the inlet of the transition piece were considered. To obtain the results, a structured grid about 5.1 millions of cells with second-order upwind scheme and coupled solver was applied. The results show the effect of the velocity and temperature along the transition piece and exit mouth due to the change of the curved section. In the exit mouth of the transition piece is identified a dimensionless peak temperature for about 1.019 in a point near to 68% of the radial edge, while in the circumferential direction the peak temperature is about 1.027 in a point near to 50% of the circumferential edge with symmetry profiles.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models
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