Complexity Study And Application Of Multi-Signals In Gas-Solid Fluidized Beds

Fluidization has been assumed as an efficient means of contacting different particles in various fields such as chemical, metallurgical and pharmaceutical industries. However, the hydro-dynamical behavior of gas-solid bed is very complex. In this paper, based on a large amount of experimental data, complexity theory are adopted as a new method to study on the multi-signals especially pressure signal in wide flow region in gas solid fluidized bed which respective diameter are 114mm and 250mm. The solid objective belong to A and B particles.Complexity theory as an important part of nonlinear science is seldom used in fluidized bed .The arithmetic of complex parameter are discussed, then compared with chaos parameter----maximum Lyapunov exponent. The experimental results show that the critical transition point of chaos state by complexity analysis corresponds well with that proposed by chaos analysis, but complexity analysis is easier to be calculated. Complexity theory not only provides a new method to analyze non-linear pressure fluctuation, but also have been proposed to be wide application foreground used in the future.Complexity parameter C2, Fluctuation Complexity parameter Cf and Algorithm Complexity parameter C(n) have been adopted to analysis pressure fluctuation signals from a gas-solid fluidized bed, the variation of the three complexity parameters with gas velocity from fixed bed, bubbling fluidization to turbulence fluidization are studied, then compared in order to characterize regime behaviors. It is demonstrated that there exists a phenomenon named "recorded" in the regime transition from fixed bed to bubbling fluidization, the three complex parameters are believed to be a new technique for flow regime identification.In this paper, Fluctuation Complexity of two different particle (A!B) are studied. It shows that Cf can identify the different fluidized characters. A new parameter I AC Iis defined as mean fluctuation difference. The results approve that I AC I is a good parameter to be a token of the diameter distributing of particles. Then a criterion of mean fluctuation difference is put forward for B particle. Fluctuation Complexity varied with different particle, static bed height diameter particle and axis position of sensor are studied.Using optic fiber sensor and pressure sensor to detect pressure fluctuation, pressure difference and particle concentration signals in order to study the characters of the bed under low velocity. Attractor and Fluctuation Complexity theory are used in this paper. Attractor analysis testifies phase space theory of Takens: measurement and analysis one state variable can reflect the qualitative character of the whole system. Experiment datas under Fluctuation Complexity analysis of three different signals all show that there exist "fluctuation" regime between aggregative fluidization and particulate fluidization. The reason is that there exists mutual competition of obtaining resource(energy and infonnation) between all subsystem or variable in transition regime. It shows that fluctuation complexity parameter is a good means to identify flow regime which is only corresponding with fluidized status.