Download or read book Analytical Investigation of Some Three dimensional Flow Problems in Turbomachines written by Frank E. Marble and published by . This book was released on 1952 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow of an incompressible inviscid fluid through a turbomachine with blade rows consisting of an infinite number of similar infinitely thin blades has been investigated theoretically in order to examine and describe the three-dimensional flow phenomena and to illustrate the methods of calculation developed.

Download or read book The Calculation of Three Dimensional Viscous Flow Through Multistage Turbomachines written by J. D. Denton and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extension of a well-established three-dimensional flow calculation method to calculate the flow through multiple turbomachinery blade rows is described in this paper. To avoid calculating the unsteady flow, which is inherent in any machine containing both rotating and stationary blade rows, a mixing process is modeled at a calculating station between adjacent blade rows. The effects of this mixing on the flow within the blade rows may be minimized by using extrapolated boundary conditions at the mixing plane. Inviscid calculations are not realistic for multistage machines and so the method includes a range of options for the inclusion of viscous effects. At the simplest level such effects may be included by prescribing the spanwise variation of polytropic efficiency for each blade row. At the most sophisticated level viscous effects and machine performance can be predicted by using a thin shear layer approximation to the Navier-Stokes equations and an eddy viscosity turbulence model. For high-pressure-ratio compressors there is a strong tendency for the calculation to surge during the transient part of the flow. This is overcome by the use of a new technique, which enables the calculation to be run to a prescribed mass flow. Use of the method is illustrated by applying it to a multistage turbine of simple geometry, a two-stage low-speed experimental turbine, and two multistage axial compressors.

Download or read book Solution adaptive Calculation of Unsteady Blade Row Interactions in Transonic Turbomachinery written by Scott M. Richardson and published by . This book was released on 1996 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the development of an implicit, viscous method for the solution of the quasi-three-dimensional flow equations for rotor-stator interaction in transonic turbomachinery. The flow algorithm is described, followed by the implicit time-marching scheme, and the one-equation turbulence model. The algorithm is implemented on an unstructured grid arrangement of locally structured micro-blocks called 'patches.' Solution-dependent adaptation is used to refine the grid in regions containing flow features which require enhanced resolution. An overlapped sliding grid interface is used to transfer flow equation information between the respective blade grids. The resulting computational algorithm has been used to perform a number of validation exercises and has been demonstrated on a modern transonic turbine stage. Where possible, these results are compared with experimental data and show the ability of the method to accurately capture the unsteady flow physics in a robust and computationally efficient manner.

Download or read book Three Dimensional Flow in Radial Turbomachinery and Its Impact on Design written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-03 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the two papers on the 'Theory of Blade Design for Large Deflections' published in 1984, a new inverse design technique was presented for designing the shape of turbomachinery blades in three-dimensional flow. The technique involves the determination of the blade profile from the specification of a distribution of the product of the radius and the pitched averaged tangential velocity (i.e., r bar-V(sub theta), the mean swirl schedule) within the bladed region. This is in contrast to the conventional inverse design technique for turbomachinery blading in two dimensional flow in which the blade surface pressure or velocity distribution is specified and the blade profile determined as a result; this is feasible in two-dimensional flow because the streamlines along the blade surfaces are known a priori. However, in three-dimensional flow, the stream surface is free to deform within the blade passage so that the streamlines on the blade surfaces are not known a priori; thus it is difficult and not so useful to prescribe the blade surface pressure or velocity distribution and determine the resulting blade profile. It therefore seems logical to prescribe the swirl schedule within the bladed region for designing a turbomachinery blade profile in three-dimensional flow. Furthermore, specifying r bar-V(sub theta) has the following advantages: (1) it is related to the circulation around the blade (i.e., it is an aerodynamic quantity); (2) the work done or extracted is approximately proportional to the overall change in r bar-V(sub theta) across a given blade row (Euler turbine equation); and (3) the rate of change of r bar-V(sub theta) along the mean streamline at the blade is related to the pressure jump across the blade and therefore the blade loading. Since the publications of those two papers, the technique has been applied to the design of a low speed as well as a high speed radial inflow turbine (for turbocharger applications) both of which showed definite improvements...

Download or read book A Three dimensional Method for the Calculation of Flow in Turbomachines Using Finite Elements on a Blade to blade Surface of Revolutions written by Cornelis Korving and published by . This book was released on 1974 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Comparison Study of Three dimensional Analysis Techniques and Loss Calculations for Axial Flow Turbines written by Richard James Timm and published by . This book was released on 1972 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A three dimensional Method for the calculation of flow in turbomachines using finite elements on a blade to blade surface of revolution written by Cornelis Korving and published by . This book was released on 1974 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Three dimensional Method for the Calculation of Flow in Turbomachines Using Finite Elements on a Blade Surface of Revolution written by Cornelis Korving and published by . This book was released on 1974 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Relaxation Solutions for Three Dimensional Transonic Flow Through a Compressor Blade Row in the Nonlinear Small Disturbance Approximation written by and published by . This book was released on 1976 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A relaxation method for calculating the three-dimensional transonic flow through a compressor blade row is discribed. The flow is taken to be steady in blade-fixed coordinates, and is treated in the nonlinear small-disturbance approximation. Details of the finite-difference formulation and the solution procedure are given. The resulting computer code is capable of operating in either of two modes: in the first, the user specifies the complete blade shape and the operating conditions, and the program finds the complete flow field, including the loading distribution on the blades. In the second, the user specifies the loading distribution over the blade surface, and the thickness distribution of the blades. The program then finds the three-dimensional flow field, including the shape of the camber surface about which the prescribed thickness must be symmetrically distributed, in order to produce the prescribed loading. Results of demonstration calculations illustrating each of these modes are included. (Author).

Download or read book An Approximate Numerical Method of Calculating a Three dimensional Flow in a Steam turbine Stage written by L. A. Shubenko-Shubin and published by . This book was released on 1966 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: TO OBTAIN A CLOSED SYSTEM OF DIFFERENTIAL EQUATIONS DESCRIBING THE MOTION OF STEAM OR GAS THROUGH A STAGE OF AN AXIAL=FLOW T*BOMACHINE, IT IS NECESSARY TO DEFINE ADDITIONAL CONDITIONS. The importance of the additional conditions as the main factors determining the design of the stage blades is shown. The equations of motion and continuity are written in terms of the heat drop and the geometric characteristics of the stage. This form of the expression permits the definition of the initial, boundary, and additional conditions, which are based on the real stage blade design, the utilization of the available design experience, and the evaluation of the stage from the point of view of strength, and fabrication and economic requirements. The analysis of the problem of three-dimensional flow through a stage of an axial-flow turbomachine has shown that four types of problem formulation are possible and a certain solution method is necessary for each one. By solving the equations of motion and continuity simultaneously, the heat-drop derivative in the axial direction is eliminated, thus making it possible to reduce the solution of the problem to the solution of an ordinary first-order differential equation using the method of lines. Since the hypothesis that the flow in the turbine is axisymmetric introduces a substantial error into the calculation results, a method is proposed which makes it possible to approximately account for the non-uniformity of the flow while retaining the mathematical advantages of the axisymmetric circulation technique. (Author).

Download or read book A Quasi Three Dimensional Method for the Calculation of Transonic Flows in Turbomachines written by Joerg Haller and published by . This book was released on 1987 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A procedure based on the iterative coupling of flow calculations on S1 blade-to-blade stream surfaces and a flow calculation on an S2 hub to tip stream surface is described. The solutions on S1 surfaces of revolution are obtained by a time marching method in finite volume form, whereas a finite difference method is used for the S2 calculation. The finite difference method uses a stream function formulation based on a passage averaging technique in order to account for non-axisymmetric flows, especially with shocks inside a blade row. Sample calculations of a single stage and a two stage compressor are presented and compared with measurements.

Download or read book Solution adaptive Calculation of Unsteady Blade Row Interactions in Transonic Turbomachinery written by Scott M. Richardson and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the development of an implicit, viscous method for the solution of the quasi-three-dimensional flow equations for rotor-stator interaction in transonic turbomachinery. The flow algorithm is described, followed by the implicit time-marching scheme, and the one-equation turbulence model. The algorithm is implemented on an unstructured grid arrangement of locally structured micro-blocks called 'patches.' Solution-dependent adaptation is used to refine the grid in regions containing flow features which require enhanced resolution. An overlapped sliding grid interface is used to transfer flow equation information between the respective blade grids. The resulting computational algorithm has been used to perform a number of validation exercises and has been demonstrated on a modern transonic turbine stage. Where possible, these results are compared with experimental data and show the ability of the method to accurately capture the unsteady flow physics in a robust and computationally efficient manner.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbomachinery Flow Physics and Dynamic Performance written by Meinhard T. Schobeiri and published by Springer Science & Business Media. This book was released on 2012-05-01 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt: With this second revised and extended edition, the readers have a solid source of information for designing state-of-the art turbomachinery components and systems at hand. Based on fundamental principles of turbomachinery thermo-fluid mechanics, numerous CFD based calculation methods are being developed to simulate the complex 3-dimensional, highly unsteady turbulent flow within turbine or compressor stages. The objective of this book is to present the fundamental principles of turbomachinery fluid-thermodynamic design process of turbine and compressor components, power generation and aircraft gas turbines in a unified and compact manner. The book provides senior undergraduate students, graduate students and engineers in the turbomachinery industry with a solid background of turbomachinery flow physics and performance fundamentals that are essential for understanding turbomachinery performance and flow complexes. While maintaining the unifying character of the book structure in this second revised and extended edition all chapters have undergone a rigorous update and enhancement. Accounting for the need of the turbomachinery community, three chapters have been added, that deal with computationally relevant aspects of turbomachinery design such as boundary layer transition, turbulence and boundary layer.

Download or read book Turbomachinery Flow Physics and Dynamic Performance written by Meinhard T. Schobeiri and published by Springer Science & Business Media. This book was released on 2006-01-16 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past three decades turbomachines experienced a steep increase in efficiency and performance. Based on fundamental principles of turbomachinery thermo-fluid mechanics, numerous CFD based calculation methods are being developed to simulate the complex 3-dimensional, highly unsteady turbulent flow within turbine or compressor stages. The objective of this book is to present the fundamental principals of turbomachinery fluid-thermodynamic design process of turbine and compressor components, power generation and aircraft gas turbines in a unified and compact manner. The book provides senior undergraduate students, graduate students and engineers in the turbomachinery industry with a solid background of turbomachinery flow physics and performance fundamentals that are essential for understanding turbomachinery performance and flow complexes.

Download or read book Three Dimensional Rotational Inviscid Flow Calculation in Axial Turbine Blade Rows written by Tony Arts and published by . This book was released on 1985 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Three Dimensional Unsteady Turbomachinery Flow Analysis written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Loosely Couple Blade Row (LCBR) numerical method is developed to analyze the unsteady flow field of a three-dimensional multi-blade-row turbomachinery problem. This method allows the use of initial blade numbers for unsteady calculation and only one blade channel per blade row is used. Circumferential average approach to obtain a converged steady solution as the initial condition is adopted for unsteady calculation. Relatively, it not only maintains the blade configuration, but is also computationally more efficient. The numerical method used is a compressible viscous finite volume algorithm solving Reynolds averaged Navier-Stokes equations. Artificial dissipation terms similar to that used by Jameson is adopted to suppress the numerical oscillations. Four-Stage Runge-Kutta scheme is used to advance the flow equations in time. Residual smoothing and multi-grid techniques are employed to accelerate the convergence. Baldwin and Lomax algebraic turbulent model is used for the calculation of eddy viscosity. The UTRC (United Technologies Research Center) large scale turbine is used here as the test case. The unsteady flow predicted correlates well with data. The results indicate that the unsteady turbomachinery flowfield can be solved with single flow channel of unequal pitch on each blade row.