Flow pattern energy input

Heat removal is accomplished by internal cooling coils or wall jacket exchangers. Hydrodynamic regimes are complex, because of complicated flow patterns, prone to quick and dramatic changes. Usually a few overall parameters are considered, such as gas residence time and holdup, solid suspension, energy input, volumetric mass transfer coefficient (sec 3.2. 

It is more difficult here to find a value of the critical Weber number, since the exact local flow conditions are not known. Usually, one takes the power density as a measure for the intensity of the eddies. The power density (symbol, with unit W/m ) is the amount of energy per that is used to establish the flow pattern. The larger the power input, the more intense and the smaller the eddies will be. 

COMBINED EFFECT OF FLOW PATTERN AND ENERGY INPUT... 

At a mixer power input of two to three times the gas stream energy, the flow pattern is controlled by the mixer [65]. If the mixer power is then increased... 

There is no particulate motion equivalent to the molecular diffusion of gases and liquids. The rate at which the randomization of the constituent particles occurs is entirely dependent on the flow characteristics or handling pattern externally imposed on the particles. There is no relative movement of the particles without an energy input to the mixture. 

CIT<0.2 The flow pattern is axial rather than radial. The final point of solid suspension moves toward the comer of the base. Further, as DIT increases, the flow strength (ocND ) increases. The overall result is a better utilization of the energy input for sohd suspension, and for DT decreases with increasing DIT. 

In design, scale-up and scale-down, it is necessary to quantify the effect of various variables on reactor performance (e.g., conversion, selectivity, volumetric productivity, etc.). This is accomplished by utilizing the reaction engineering methodology in developing a reactor model. Such a steady-state model (Figure 1) often contains a description of the reactor idealized flow pattern on the left hand side (LHS) of the chemical species and energy conservation laws i.e. as input-output terms, and the rate... 

---