Simulation and Control of A Liquid Flow Calibration System
碩士 === 中原大學 === 化學工程研究所 === 82 === The Fluid transients caused by the enormous change of flow rate may be harmful to the piping system. The flow and pressure process in a liquid flow calibration system have highly interatcion. The...
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| Other Authors: | |
| Format: | Others |
| Language: | zh-TW |
| Published: |
1994
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| Online Access: | http://ndltd.ncl.edu.tw/handle/63500529684150169097 |
| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 82 === The Fluid transients caused by the enormous change of flow
rate may be harmful to the piping system. The flow and pressure
process in a liquid flow calibration system have highly
interatcion. The selection of the controlled point of pressure
could have large effect on the control performance. The main
purpose of this reserach is to concen the related topics
smoothing the operation of the calibration system. Mathematical
models of the fluid transients were derived by the
principle of the mass and momentum balance. The
characteristic method is applied for numerical analysis. The
simulation studies on the fluid transients of the calibration
system were executed by this method. A steady state equation
governing the flow and pressure relation was also derived for
the control purpose. Simulation results show that the elapsed
time of the valve closing have the great effect on the
fluid transients. The increase of the pressure during the
transient is larger for the shorter closing time. The different
valve characteristics cause the different effect on the system.
The equal percentage valves create the largest change of
pressure. The manipulation of the valve on the bypass provides
the good pressure control of the main pipeline while the flow
rate change. A parital decoupler was applied to reduce the
interaction between the flow and pressure control loop. It
shows that the controlled point of pressure nearest to the
closingvalve have the best control performance.
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