Cascades flow rates between stages

Equations (8.3.26) and (8.3.27) are generally applicable to all types of CSTR cascades. If one recognizes that the use of such cascades is almost invariably restricted to liquid systems and that in such systems density changes caused by reaction or thermal effects are usually quite small, then additional relations or simplifications can be developed from these starting equations. In particular, this situation implies that at steady state the volumetric flow rate between stages is substantially constant. It also implies that for each reactor, 7, = t,, and that the following relation between concentration and fraction conversion is appropriate ... 

Flow rates between stages, tapered cascades... 

A two-stage cascade refrigeration system is shown helow. The refrigerant is HI 34a. It consists of two ideal vapor-compression cycles with heat exchange between the condenser of the lower-temperature cycle and the evaporator of the hi er-temperature cycle. The hotter cycle operates between 0.7 MPa and 0.35 MPa, while the cooler cycle operates between 0.35 MPa and 0.12 MPa. If the flow rate in the hotter cycle is 0.5 mol/s, determine the following ... 

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