A Computational Geometry for the Blades and Internal Flow Channels of Centrifugal Compressors

1982 ◽  
Author(s):  
M. V. Casey
Keyword(s):  
Computational Geometry ◽  
Computer Aided Design ◽  
Design Procedure ◽  
Internal Flow ◽  
Geometrical Shape ◽  
Parametric Form ◽  
Centrifugal Compressors ◽  
Flow Channels ◽  
Computer Aided ◽  
Aided Design

A new computational geometry for the blades and internal flow passages of centrifugal compressors is described and examples of its use in the design of industrial compressors are given. The method makes use of Bernstein-Bezier polynomial patches to define the geometrical shape of the flow channels. This has the following main advantages: the surfaces are defined by analytic functions which allow systematic and controlled variation of the shape and give continuous derivatives up to any required order; and the parametric form of the equations allows the blade and channel coordinates to be very simply obtained at any number of points and in any suitable distribution for use in subsequent aerodynamic and stress calculations and for manufacture. The method is particularly suitable for incorporation into a computer aided design procedure.

A Computational Geometry for the Blades and Internal Flow Channels of Centrifugal Compressors

1983 ◽  
Vol 105 (2) ◽  
pp. 288-295 ◽  
Author(s):  
M. V. Casey
Keyword(s):  
Computational Geometry ◽  
Computer Aided Design ◽  
Design Procedure ◽  
Internal Flow ◽  
Geometrical Shape ◽  
Parametric Form ◽  
Centrifugal Compressors ◽  
Flow Channels ◽  
Computer Aided ◽  
Aided Design

A new computational geometry for the blades and flow passages of centrifugal compressors is described and examples of its use in the design of industrial compressors are given. The method makes use of Bernstein-Bezier polynomial patches to define the geometrical shape of the flow channels. This has the following main advantages: the surfaces are defined by analytic functions which allow systematic and controlled variation of the shape and give continuous derivatives up to any required order: and the parametric form of the equations allows the blade and channel coordinates to be very simply obtained at any number of points and in any suitable distribution for use in subsequent aerodynamic and stress calculations and for manufacture. The method is particularly suitable for incorporation into a computer-aided design procedure.

The Use of Bezier Polynomial Patches to Define the Geometrical Shape of the Flow Channels of Compressors

1988 ◽  
Author(s):  
Wang Qinghuan ◽  
Huang Xiaoyan
Keyword(s):  
Computer Aided Design ◽  
Design Procedure ◽  
Spanwise Direction ◽  
Geometrical Shape ◽  
Construction Process ◽  
Load Models ◽  
Flow Channels ◽  
Aided Design ◽  
Further Development ◽  
Surface Construction

Based on the method of Casey (1), the present paper makes further development in using Bezier polynomial patches to define the geometrical shape of the flow channels of compressors. There are two advantages in this new method. First, in the geometrical construction process the blade profile and the contour of impeller’s meridional channel can be given by the same number of patches of the same degree so as to avoid more complicated repeat computations. Second, for curved surface construction there are no restrictions of linearity in the spanwise direction in order to match the distribution of flow angles at the inlet better and to fit the needs of various load models. Some examples have shown that the shapes produced by Bezier polynomial patches are general enough to be used in the design of new compressors and in approximation of the geometry of existing ones. The method is particularly suitable for incorporation into a computer-aided design procedure.

scholarly journals Computer-Aided Sketching: Incorporating the Locus to Improve the Three-Dimensional Geometric Design

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1181 ◽  
Author(s):  
José Ignacio Rojas-Sola ◽  
David Hernández-Díaz ◽  
Ricardo Villar-Ribera ◽  
Vicente Hernández-Abad ◽  
Francisco Hernández-Abad
Keyword(s):  
Computational Geometry ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
Geometric Design ◽  
Curved Surfaces ◽  
Two Dimensional ◽  
Technical Design ◽  
Computer Aided ◽  
Aided Design

This article presents evidence of the convenience of implementing the geometric places of the plane into commercial computer-aided design (CAD) software as auxiliary tools in the computer-aided sketching process. Additionally, the research considers the possibility of adding several intuitive spatial geometric places to improve the efficiency of the three-dimensional geometric design. For demonstrative purposes, four examples are presented. A two-dimensional figure positioned on the flat face of an object shows the significant improvement over tools currently available in commercial CAD software, both vector and parametric: it is more intuitive and does not require the designer to execute as many operations. Two more complex three-dimensional examples are presented to show how the use of spatial geometric places, implemented as CAD software functions, would be an effective and highly intuitive tool. Using these functions produces auxiliary curved surfaces with points whose notable features are a significant innovation. A final example provided solves a geometric place problem using own software designed for this purpose. The proposal to incorporate geometric places into CAD software would lead to a significant improvement in the field of computational geometry. Consequently, the incorporation of geometric places into CAD software could increase technical-design productivity by eliminating some intermediate operations, such as symmetry, among others, and improving the geometry training of less skilled users.

Computer Aided Design of a New Universal Clamping Mechanism

2014 ◽  
Vol 597 ◽  
pp. 417-420
Author(s):  
Jeremy Zheng Li
Keyword(s):  
3D Modeling ◽  
Computer Aided Design ◽  
High Speed ◽  
Manufacturing Industry ◽  
Cost Effective ◽  
Geometrical Shape ◽  
Automated Production ◽  
Computer Aided ◽  
New Type ◽  
Aided Design

The tooling and fixture play important roles in manufacturing and production. It affects both product quality and quantity. Better tooling and fixture can also promote cost-effective manufacturing process. This paper introduces a new type of universal clamping mechanism based on computer-aided 3D modeling, engineering structural analysis, and prototype testing. It can be applied to easily and reliably clamp different geometrical shape of work pieces per user requirements. This new clamping mechanism, with less moving components, can assist manufacturing industry for high speed production, easy part handling, precise clamping, and lower tooling cost. Keywords: Computer-aided design, automated production, 3D modeling, cost-effective, high speed manufacturing, engineering analysis, optimization, efficient;

Computer Aided Design of Mixed Flow Turbines for Turbochargers

1979 ◽  
Vol 101 (3) ◽  
pp. 440-448 ◽  
Author(s):  
N. C. Baines ◽  
F. J. Wallace ◽  
A. Whitfield
Keyword(s):  
Mass Flow ◽  
Computer Aided Design ◽  
High Speed ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Design Procedure ◽  
Mixed Flow ◽  
Computer Aided ◽  
Design Calculations ◽  
Aided Design

The paper describes a comprehensive computer aided design procedure and its use to investigate mixed flow turbines for automotive turbocharger applications. The outside dimensions of rotor and casing as well as blade angles are determined from one-dimensional design and off design calculations, the detailed blade shape from quasi-three-dimensional analysis and mechanical stressing and vibration programs, and geometric data are presented as outside views and sections of the rotor by a graphics subroutine. The procedure consists of a series of separate programs rather than a single program, so that the designer’s intervention at each stage of the process can be applied. Two mixed flow rotors were designed, manufactured and tested in a specially designed high speed dynamometer. The first was intended to achieve a substantial increase in mass flow over the reference radial rotor without loss of efficiency, while the latter was intended as a direct replacement of the reference radial rotor, but should give more favorable pulse performance when operating in conjunction with an engine due to changes in the operating map viz: a) lower tip speeds for best efficiency, and b) flatter mass flow characteristics. Both effects were predicted by analysis and confirmed by tests.

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