Experimental and computational studies of the dynamics of a fixed bed chemical reactor

Experimental measurements of the temperature response of a fixed bed reactor to sinusoidal disturbances in the feed concentration, temperature, and flow rate show that a simple one-dimensional mathematical model with distributed thermal capacitance satisfactorily describes the dynamic behavior of the reactor for modest excursions about an operating point. The reaction considered is a liquid-phase exothermic reaction whose rate depends on the concentration of two reactants and the temperature. A computational analysis reveals that the amplitude and phase of the traveling concentration and temperature waves are influenced in a complex manner by the interaction between the two waves. The interaction, which is treated here as interference between traveling waves, is made complex by the difference in the rates of propagation of the temperature and concentration waves and by the variation of their speeds throughout the bed.