Multipassage heat exchangers are normally designed with the assumption that the fluid stream is uniformly divided among all the parallel channels. But, in practice, an improper entrance configuration or imperfect flow passages create a flow maldistribution. Paired-channel exchangers in which the channels are continuously distributed as a function of flow rate have been investigated. Two cases of continuous maldistribution have been considered: (1) #x201C;one-side#x201D; nonuniformity, the other side having a uniform flow distribution, and (2) #x201C;both-sides#x201D; nonuniformity, where each channel pair serves as a balanced counterflow exchanger. Comparison with discrete distribution models investigated by other authors shows that a two-size model is adequate to predict the overall effectiveness of the heat exchangers in most cases of practical interest.
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