Hot air for a large-scale drying operation is to be produced by routing the air over a tube bank (unmixed), while products of combustion are routed through the tubes. The surface area of the cross-flow heatexchanger is
(a) What are the air and gas outlet temperatures?
(b) After extended operation, deposits on the innertube surfaces are expected to provide a foulingresistance of
(c) The heat exchanger performance may be improved by increasing the surface area and/or the overall heat transfer coefficient. Explore the effect of such changes on the air outlet temperature for
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