Plug flow, reactor model space velocity

In a tubular reactor, the concentration and temperature may vary both in time and space. One speaks about a distributed system. The ideal plug flow reactor (PFR) model is the most used. Because of the flat velocity profile, the concentrations and temperature varies only along the length. Consider for simplification a homogeneous reaction. The unsteady state material balance of the reactive species leads to the following equation ... 

Model of ideal desaturation (model with plug flow regime) is the favorable approximation for calculation of reactor parameters [3,4,6] any cross-section normal for flow, weight hour space velocity w and flow s properties (pressure, temperature and reaction mixture structure) are uniform narrow distribution of reagents residence times in reaction zone Xpr diffusion in the axial line (coplanar mixing or turbulence) in comparison with weight hour space velocity is negligible low. 

It is useful to relate the space-velocity to other simple models of practical reactor performance. Expressions describing conversion in model reactors are provided later (section 2.5). It is convenient to summarize expressions for the (well-stirred) simple batch reactor and the single-pass, plug flow reactor here, considering a reaction under complete mass transport control. For the batch reactor, the limiting current is given by ... 

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