Charlie at Full Speed

The New World ◽  
2021 ◽  
pp. 14-17
Keyword(s):  
1982 ◽  
Author(s):  
Kathleen Fisher ◽  
Keyword(s):  

2021 ◽  
Vol 20 (2) ◽  
pp. 223-224
Author(s):  
Scott W. Woods ◽  
Jimmy Choi ◽  
Daniel Mamah

1981 ◽  
Vol 5 (1) ◽  
pp. 5-32 ◽  
Author(s):  
Lois-Ellin Datta
Keyword(s):  

Author(s):  
J. H. Kim ◽  
T. W. Song ◽  
T. S. Kim ◽  
S. T. Ro

A simulation program for transient analysis of the start-up procedure of heavy duty gas turbines for power generation has been constructed. Unsteady one-dimensional conservation equations are used and equation sets are solved numerically using a fully implicit method. A modified stage-stacking method has been adopted to estimate the operation of the compressor. Compressor stages are grouped into three categories (front, middle, rear), to which three different stage characteristic curves are applied in order to consider the different low-speed operating characteristics. Representative start-up sequences were adopted. The dynamic behavior of a representative heavy duty gas turbine was simulated for a full start-up procedure from zero to full speed. Simulated results matched the field data and confirmed unique characteristics such as the self-sustaining and the possibility of rear-stage choking at low speeds. Effects of the estimated schedules on the start-up characteristics were also investigated. Special attention was paid to the effects of modulating the variable inlet guide vane on start-up characteristics, which play a key role in the stable operation of gas turbines.


1938 ◽  
Vol 68 (1) ◽  
pp. 1-16 ◽  
Author(s):  
James A. Chiles ◽  
Aura E. Severinghaus

1. An ultracentrifuge is described in which the rotor is driven by a compressed air turbine, and is spun in an evacuated chamber to minimize friction and heating. The rotating parts are supported by a cushion of air in an air bearing. 2. The centrifuge rotor holds 10 test tubes inclined at 45° to the axis, and has a capacity of 55 cc. It is operated at a maximum speed of 51,000 R.P.M., which develops at the top of the fluid column in the test tubes a centrifugal field of over 100,000 times gravity, and at the bottom of the fluid column a field of over 200,000 times gravity. 3. By means of a reverse turbine, the rotor can be brought to a stop from full speed in a relatively short time. 4. A precession damping device is described, which effectively damps the precession and wobbling of the rotor that usually occurs at certain speeds in machines of this type. 5. A relatively long section of shaft is used between the centrifuge rotor and lower bearings. This prevents vibrations from being appreciably transmitted through the shaft to the lower bearings and driving mechanism, and results in a negligible wear on the bearings. 6. The driving mechanism is designed so that the positions of its parts are adjustable, and so that the driving mechanism may be dismantled without disturbing these adjustments.


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