Dynamic modeling of agitated pulp stock chests.Application: Identification of the type and degree of non-ideal flow in a pulp stock chest allows mills to take corrective measures to improve uniformity in downstream processes. The chief purpose of agitated ag·i·tate v. ag·i·tat·ed, ag·i·tat·ing, ag·i·tates v.tr. 1. To cause to move with violence or sudden force. 2. pulp stock chests is to reduce high-frequency variability in mass concentration, freeness, and other quality factors. These chests behave as low-pass filters A filter that blocks high frequencies and allows lower frequencies to pass through. Such filters are used in devices such as POTS splitters that direct phone and DSL signals to different lines. Contrast with high-pass filter. to complement the action of control loops, which only control low-frequency variability. Dynamic tests made on industrial and scale-model stock chests show non-ideal flows such as channeling, recirculation Noun 1. recirculation - circulation again circulation - the spread or transmission of something (as news or money) to a wider group or area , and stagnant zones. These flows reduce the degree of upset attenuation Loss of signal power in a transmission. Attenuation The reduction in level of a transmitted quantity as a function of a parameter, usually distance. It is applied mainly to acoustic or electromagnetic waves and is expressed as the ratio of power densities. at frequencies higher than the cut-off cut-off Anesthesiology The point at which elongation of the carbon chain of the 1-alkanol family of anesthetics results in a precipitous drop in the anesthetic potential of these agents–eg, at > 12 carbons in length, there is little anesthetic activity, frequencies of paper machine control loops. We have developed a dynamic model of agitated pulp stock chests, incorporating these non-ideal flows. In this paper, we explore the excitation excitation Addition of a discrete amount of energy to a system that changes it usually from a state of lowest energy (ground state) to one of higher energy (excited state). For example, in a hydrogen atom, an excitation energy of 10. design required to estimate the model parameters and the effect of process variables on disturbance attenuation. The variables examined include the impeller speed, pulp feed and exit location, fiber mass concentration (consistency), and pulp flow rate through the chest. Test results show that the percentage of channeling and the degree of disturbance attenuation are significantly "affected by the location of the input and output in the chest. At higher pulp flow rates through the chest and fiber mass concentration greater than 3%, the system is prone to a high percentage of channeling and a low degree of upset attenuation. We found that chests designed using the criterion of file onset of complete motion do not necessarily lead to a fully mixed system, especially at fiber mass concentration greater than 3%. S! Ein-Mozaffari and Bennington are with the Department of Chemical & Biological Engineering, and Dumont is with the Department of Electrical & Computer Engineering, The University of British Columbia Locations Vancouver The Vancouver campus is located at Point Grey, a twenty-minute drive from downtown Vancouver. It is near several beaches and has views of the North Shore mountains. The 7. , Pulp and Paper Centre, 2385 East Mall, Vancouver, BC, V6T 1Z4, Canada; Kammer is with the Pulp and Paper Research Institute of Canada, 3800 Wesbrook Mall, Vancouver, BC, Canada. Email Bennington at cpjb@chml.ubc.ca. |
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