Indirect Cooling Heat Exchange Across the Reactor Wall

Indirect Cooling Heat Exchange Across the Reactor Wall 

The problem of the determination of the overall heat transfer coefficient can be simplified if one considers that the overall resistance to heat transfer consists of several resistances in series [Eq. (17)]. 

The first two terms, representing the liquid film at the inner wall of the reactor and any polymer deposit, only depend on the reactor contents, that is, on the agitation 

This expression is valid for Newtonian fluids therefore with polymers its validity must be verified. In this correlation, the dimensionless numbers are defined in Eq. (19). Here the Reynolds number (Re) is expressed for a stirred tank where the flow rate corresponds to the tip speed of the agitator. 

for a given reaction mass, the heat transfer coefficient of the internal film can be influenced by the revolution speed of the agitator and its diameter. The value of z, characterizing the internal part of the equipment factor, can be calculated using the geometric characteristics of the reactor. Some typical values of the agitator constant are given in Table 11.3. The value of y can either be calculated 

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