PDF Publication Title:
Text from PDF Page: 083
Chapter 4. Explicit/Multi-Parametric MPC Control of PSA Systems eventually leading to poor model identification. 2. The switching time for the pulse, tswitch, i.e. the time for which the signal stays constant before switching to the new (random) value. Very high val- ues of switching time produces input-output behavior close to a step input change and thus does not offer any additional advantages. On the other hand, very low switching times do not allow PSA system to reveal its com- plete dynamic nature, apart from causing possible degradation of switch valve equipment. In order to fix the first parameter, open loop experiments are performed with step signals of various step sizes, and a value of three seconds is finally selected. For tswitch, a well structured closed loop simulations based approach is employed wherein three random pulse signals are designed with the same magnitude (first parameter) but with different switching times. Figures 4.8a, 4.8b, and 4.9, shows the input-output response for input signals with tswitch of 5, 20, and 79, respec- tively. The best switching time is decided based on their closed loop performances which is discussed in section 4.5.1. The fact that PSA operation is periodic and the manipulative variable is time itself, makes the choice of sampling frequency of measurements requiring additional attention. The sampling interval cannot be a fixed value for PSA operation, since all the process steps change and repeat after every cycle (time), whose duration in turn keeps changing (Eq. 4.19) in a closed loop setting. To overcome this challenge, purity-adsorption time measurements are recorded every cycle instead of fixed intervals. The measurements are made at product end (z = L) of the first bed, when the adsorption step of this bed is about to finish [83]. Multiple measurements, before the end of adsorption step and after it are also possible but are expected to increase the measurement cost, and the time 83PDF Image | Operation and Control of Pressure Swing Adsorption Systems
PDF Search Title:
Operation and Control of Pressure Swing Adsorption SystemsOriginal File Name Searched:
Khajuria-H-2011-PhD-Thesis.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)