Effects of chaotic temperature fluctuations on the heat transfer coefficient in liquid-liquid-solid fluidized beds

The effect of chaotic temperature fluctuations on the immersed heater-to-be d heat transfer coefficient (h) are investigated in a liquid-liquid-so lid fluidized bed (0.152 m ID x 2.5 in in height). The time series of temperatu re fluctuations are measured and analyzed by means of the multidimensional phase space portraits and Kolmogorov entropy (K), in order to characterize the chaotic behavior of heat transfer coefficient fluctuations in the bed. The overall heat transfer coefficient is inversely proportional to the Kolm ogorov entropy of temperature fluctuations, as well as the fluctuation rang e of heat transfer coefficient (Deltah(i)). The Kolmogorov entropy and fluc tuation range of the heat transfer coefficient (Deltah(i)) increase with in creasing dispersed phase velocity, but decrease with increasing particle si ze. However, they attain their minima with variation of the continuous phas e velocity as well as the bed porosity, at which point the flow regime of p articles in the beds changes. The overall heat transfer coefficient is dire ctly correlated with the Kolmogorov entropy, as well as the fluctuation ran ge of heat transfer coefficient.