Residence Time Distribution for a Laminar Flow Tubular Reactor

RESIDENCE TIME DISTRIBUTION FOR A LAMINAR FLOW TUBULAR REACTOR 

Beeause u varies with r, the residenee times of the various fluid elements will also vary with r. The time that it will take a fluid element to traverse the reaetor of length L is 

The fluid at the eenterline is moving the fastest, so this material will be the first to leave. It leaves at a time given by 

The fraetion of the volumetrie flowrate that oeeurs in the region bounded by r = 0 and r = r is equal to F(t) where t is equal to the time neeessary for a fluid element to traverse the reaetor length at a given r. 

Volumetrie flowrate between r = 0 and r = r Total volumetrie flowrate 

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