Fin efficiency and mechanisms of heat exchange through fins in multi-stream plate-fin heat exchangers: development and application of a rating algorithm

An alternate algorithm for the analysis of multistream plate fin heat exchangers

“…If we split a heat exchanger into a large number of small segments, each individual segment will qualify to be designed by the area splitting method. Some of the existing design suggests dividing the exchanger into arbitrary number of small segments at the beginning [24,26,27]. However, such partitioning may result in divergence of solution if the initial guess of the temperature profile is a poor one.…”

“…For instance, the heat exchanger of example II in Ref. [25] does not yield results when Prasad's algorithm [27] is employed and the exchanger is divided into 20 or more parts. Fig.…”

“…In a later improvement Prasad [26] showed that the assumption of zero temperature gradient over the fins near the channel centreline made [20,24] could result in considerable error. He suggested a method of correction to this based on the mechanism of local heat transfer and developed a computational algorithm [27] using this new formalism.…”

“…Unlike Haseler [12], Prasad and his co-workers [24,26,27] have employed the modified shooting method to solve the governing equations. Their method could suppress the tendency of divergence as it corrected the guess temperature at each segment.…”

“…A hypothetical adiabatic plane may be assumed to exist outside the central stream and its location can be computed by analytically extending the temperature profile [26,27]. Different authors have accounted for this phenomenon in different ways.…”