173 research outputs found
POGO Instabilities Suppression Evaluation
A dynamic (frequency response) analysis was made of a liquid oxygen feed system consisting of a low-speed inducer, a high-speed main pump and a positive displacement pulser utilized for simulating pogo induced pressure oscillations. Based on the results of the analysis, an active control system for suppression of pulser generated pressure oscillations was designed, fabricated and tested. The test results verified that the suppressor was effective in attenuating the generated pressure oscillations over the frequency range from 10 to 30 Hz
Optical measurement of pressure transient-induced flow in hydraulic systems
The project is concerned with observation of fluid movement and transducer
diaphragm deformation, under the influence of large pressure transients of the order
of 2000 PSI (140 bar). Large pressure surges often occur in hydraulic systems and this
coupled with sharp rise times of the order of 100 μs, causes damage to the surface of
the transducer diaphragm or face and subsequently the pressure reading mechanisms. [Continues.
Modification of the rotary machining process to improve surface form
Planing and moulding operations carried out within the woodworking industry make
extensive use of rotary machining. Cutter-marks are produced on the timber surface
which are generally accepted as unavoidable. More noticeable surface defects may be
produced by such factors as cutter-head imbalance, and until recently most research has
concentrated on removing these defects. When a high quality finish is required, a further
machining operation, such as sanding, is often required to remove cutter-marks. What is
required, is a modified machining process which combines a surface closer to the ideal
fixed knife finish, whilst retaining the flexibility, practicality and cost effectiveness of
rotary machining. [Continues.
- …