Discussion on Control Points of Surge and Anti-surge of Centrifugal Compressor

Design of a Centrifugal Compressor Using CFD Analysis: Part I — Preliminary Design and Geometry Modification

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2014-36051 ◽

2014 ◽

Cited By ~ 1

Author(s):

K. V. Muralidharan

Keyword(s):

Centrifugal Compressor ◽

Inverse Method ◽

Automated Design ◽

Control Points ◽

Two Dimensional ◽

Present Scheme ◽

Blade Loading ◽

Design Scheme ◽

User Friendly ◽

Blade Geometry

The centrifugal compressors are used in a wide variety of turbo machines ranging from low-pressure fans for cooling of electric motors to high-pressure ratio gas turbine compressors, from tiny cryogenic coolers to large industrial petrochemical compressor stations. An automated design scheme making use of Navier Stokes equation and Artificial Neural Network is envisaged as in figure 1. The present work describes a user friendly scheme to carry out blade geometry generation and to carry out preliminary designs that are two of the most important steps of the automated design scheme. Present paper describes a robust method to carry out these two steps. This paper also describes a method adopted to decide on viable design space. In the blade generation steps, present method was applied to that obtained by other methods reported in literature. It was found that the present scheme could replicate the centrifugal compressor geometry with just six parameters as compared to many more by others. In Mihai[1], use of adjoint method is used for optimization of NASA rotor. The design had 28 parameters. In Trigg[2], a systematic approach for optimization of a two dimensional blade design is reported. Two dimensional profile is defined by seventeen parameters. In Wang Hong liang[3] an optimization based on particle swarm principle is made use of to optimize the blade angle distribution at hub and shroud and had seven control points to do this. In order to minimize the number of control points, Asimara and Goto[4], used inverse method. Here blade loading at hub and shroud is the input to a inverse method to generate the blade geometry. Optimizer works on the blade loading. The generated geometry is analyzed by CFD calculations. From the above references, it is clear that the present scheme is a user friendly general method.

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Practical Realization of a Reference System for Earth Dynamics by Satellite Methods

International Astronomical Union Colloquium ◽

10.1017/s0252921100051150 ◽

1975 ◽

Vol 26 ◽

pp. 341-380 ◽

Cited By ~ 5

Author(s):

R. J. Anderle ◽

M. C. Tanenbaum

Keyword(s):

Reference Frame ◽

Polar Motion ◽

Pole Position ◽

Control Points ◽

Significant Information ◽

Crustal Motion ◽

Average Reference ◽

Future Data ◽

Existing Data

AbstractObservations of artificial earth satellites provide a means of establishing an.origin, orientation, scale and control points for a coordinate system. Neither existing data nor future data are likely to provide significant information on the .001 angle between the axis of angular momentum and axis of rotation. Existing data have provided data to about .01 accuracy on the pole position and to possibly a meter on the origin of the system and for control points. The longitude origin is essentially arbitrary. While these accuracies permit acquisition of useful data on tides and polar motion through dynamio analyses, they are inadequate for determination of crustal motion or significant improvement in polar motion. The limitations arise from gravity, drag and radiation forces on the satellites as well as from instrument errors. Improvements in laser equipment and the launch of the dense LAGEOS satellite in an orbit high enough to suppress significant gravity and drag errors will permit determination of crustal motion and more accurate, higher frequency, polar motion. However, the reference frame for the results is likely to be an average reference frame defined by the observing stations, resulting in significant corrections to be determined for effects of changes in station configuration and data losses.

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On-farm udder health monitoring

Tierärztliche Praxis Ausgabe G Großtiere / Nutztiere ◽

10.1055/s-0038-1624622 ◽

2011 ◽

Vol 39 (02) ◽

pp. 95-100

Author(s):

J. C. van Veersen ◽

O. Sampimon ◽

R. G. Olde Riekerink ◽

T. J. G. Lam

Keyword(s):

Management Practices ◽

Health Management ◽

Action Plan ◽

Real Life ◽

Health Data ◽

Control Points ◽

Udder Health ◽

Critical Control Points ◽

On Farm ◽

Clinical Problems

SummaryIn this article an on-farm monitoring approach on udder health is presented. Monitoring of udder health consists of regular collection and analysis of data and of the regular evaluation of management practices. The ultimate goal is to manage critical control points in udder health management, such as hygiene, body condition, teat ends and treatments, in such a way that results (udder health parameters) are always optimal. Mastitis, however, is a multifactorial disease, and in real life it is not possible to fully prevent all mastitis problems. Therefore udder health data are also monitored with the goal to pick up deviations before they lead to (clinical) problems. By quantifying udder health data and management, a farm is approached as a business, with much attention for efficiency, thought over processes, clear agreements and goals, and including evaluation of processes and results. The whole approach starts with setting SMART (Specific, Measurable, Acceptable, Realistic, Time-bound) goals, followed by an action plan to realize these goals.

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