Attributes of the inlet streams to a heat exchanger are as follows:
The product in Btu/hr- OF for the heat exchanger is given by
where eh and 
e are the capacities in Btu/lir-E Using only s-NTU method, (a) Find the outlet temperatures and rating for a parallel-flow arrangement. (b) Find the outlet temperatures and rating for a counter flow arrangement.
(c) Find the outlet temperatures and rating if two of these heat exchangers are placed in series and are operated in a parallel-flow arrangement. What are the interface temperatures?
(d) Find the outlet temperatures and rating if two of these heat exchangers are placed in series and operated in a counter flow arrangement. What are the interface temperatures?
(e) Find the outlet temperatures and rating if two of these heat exchangers are placed in parallel (even-mass-flow-rate split) and operated in a parallel-flow arrangement.
(f) Find the outlet temperatures and rating if two of these heat exchangers are placed in parallel (even-mass-flow-rate split) and operated in a counter flow arrangement.
(g) Based on the results of the above, discuss the utility of placing parallel and counter flow heat exchangers in series and parallel for added heat transfer capability.