Flow in a model turbine stator

In view of the complex nature of the flowfield in the hot section of gas turbine engines, the need to predict heat transfer and flow losses, the possible appearance of separation and strong secondary flows, etc., the present effort is focusing upon a Navier-Stokes approach to the three dimensional turbine stator problem. The advantages of a full Navier-Stokes approach are clear since when combined with a suitable turbulence model these equations represent the flow and heat transfer physics. In particular, the Navier-Stokes equations accurately represent possible separated regions and regions of significant secondary flow. In addition, the Navier-Stokes approach allows representation of the entire flow field by a single set of equations, thus avoiding problems associated with representing different regions of the flow by different equations and then matching flow regions

Development of a three-dimensional supersonic inlet flow analysis

A method for computing three dimensional flow in supersonic inlets is described. An approximate set of governing equations is given for viscous flows which have a primary flow direction. The governing equations are written in general orthogonal coordinates. These equations are modified in the subsonic region of the flow to prevent the phenomenon of branching. Results are presented for the two sample cases: a Mach number equals 2.5 flow in a square duct, and a Mach number equals 3.0 flow in a research jet engine inlet. In the latter case the computed results are compared with the experimental data. A users' manual is included

Calculation of helicopter rotor blade/vortex interaction by Navier-Stokes procedures

Interactions of a modern rotor blade with concentrated tip vortices from the previous blades can have a significant influence on the airloads and the aeroacoustics of a helicopter. A better understanding of the blade/vortex interaction process and a method of analyzing its flow field would provide valuable help in the design of helicopters. The work discussed herein represents an initial effort in applying a 3-D, time-dependent Navier-Stokes simulation to the blade vortex interaction problem. The numerical approach is the Linearized Block Implicit (LBI) technique. In this initial effort, consideration is given to the interaction of a wing of idealized geometry and a vortex whose axis is aligned at an arbitrary angle to the wing. The calculations are made for laminar, subsonic flow, and show the time dependent pressure distribution and flow fields resulting from the interaction

Turbine stator flow field simulations

The increased capability and accessibility of modern computers, coupled with increasingly sophisticated and accurate numerical and physical modeling, has led to a marked impact of numerical simulations upon current turbine design and research problems. The turbine section represents a considerable challenge as it contains significant regions of complex three-dimensional flow, including both aerodynamic and heat transfer phenomena. The focus of the present effort is the development of an efficient and accurate three-dimensional Navier-Stokes calculation procedure for application to the turbine stator and rotor problems. In particular, an effective procedure is sought which: (1) adequately represents the flow physics, (2) allows for sufficient resolution in regions of small length scale, and (3) has sufficiently good convergence properties so as to allow use on a regular basis

Two- and three-dimensional turbine blade row flow field simulations

Work performed in the numerical simulation of turbine passage flows via a Navier-Stokes approach is discussed. Both laminar and turbulent simulations in both two and three dimensions are discussed. An outline of the approach, background, and an overview of the results are given

Two- and three-dimensional blade vortex interactions

A three-dimensional time dependent Navier-Stokes analysis was applied to the rotor blade vortex interaction (BVI) problem. The numerical procedure is an iterative implicit procedure using three point central differences to represent spatial derivatives. A series of calculations were made to determine the time steps, pseudo-time steps, iterations, artificial dissipation level, etc. required to maintain a nondissipative vortex. Results show the chosen method to have excellent non-dissipative properties provided the correct parameters are chosen. This study was used to set parameters for both two- and three-dimensional blade vortex interaction studies. The two-dimensional study considered the interaction between a vortex and a NACA0012 airfoil. The results showed the detailed physics during the interaction including the pressure pulse propagating from the blade. The simulated flow physics was qualitatively similar to that experimentally observed. The 2-D BVI phenomena is the result of the buildup and violent collapse of the shock waves and local supersonic pockets on the blade surfaces. The resulting pressure pulse build-up appears to be centered at the blade leading edge. The three-dimensional interaction study considered the case of a vortex at 20 deg incidence to the blade leading edge. Although the qualitative results were similar to that of the two-dimensional interaction, details clearly showed the three-dimensional nature of the interaction process

Place, Space and Memory in the Old Jewish East End of London: an Archaeological Biography of Sandys Row Synagogue, Spitalfields and its Wider Context

Sandys Row (London E1) is the only functioning Ashkenazi (Eastern European Jewish) Synagogue in Spitalfields and the oldest still functioning Ashkenazi synagogue in London. Located in an area, which from the mid­late nineteenth century until WWII was the centre of London’s Jewish population, it is one of the last surviving witnesses to a once vibrant and dynamic heritage that has now virtually disappeared. This area has been the first port of call for refugees for centuries, starting with French Protestant Huguenots in the eighteenth century, then Jews fleeing economic hardship and pogroms in Eastern Europe in the nineteenth century followed by Bangladeshi Muslims in the twentieth century. Using a broadly archaeological analysis based very closely on the sort of practice widely used in church archaeology, the authors argue that much can be inferred about wider social and cultural patterns from a study of architectural space at Sandys Row and its associated material culture. This is the first such archaeological study undertaken of a synagogue in Britain and offers a new perspective on wider issues regarding the archaeological definition of religious practice and religious material culture

Feasibility Study for an Advanced Coal Fired Heat Exchanger/Gas Turbine Topping Cycle for a High Efficiency Power Plant. Technical Report, January 1, 1993--March 31, 1993

The overall objective of this project is to prove the feasibility of AFR`s concepts for a high efficiency coal-fired generating plant using the REACH/Exchanger concept to power an externally fired gas turbine. The computational REACH reactor was modeled with PCGC-2. The reactor geometry, inlet flow rates and configurations were investigated via modeling in order to get an optimum operation condition, with which a thorough coal and gas mixture and a required coal particle dispersion can both be achieved. This is to ensure the efficiencies of both coal combustion and aerodynamic cleaning. The aerodynamic cleaning effect of the tertiary air injection was modeled with CELMINT. Various injection schemes investigated show the dramatic impact of the tertiary air and the injection positions on the overall air flow pattern in the reactor which is one of the major influencing factors on the particle dispersion. It is clearly demonstrated that an optimum tertiary injection scheme with a reasonable flow rate is able to keep the heat exchange tubes from particle fouling