Math/Physic/Economic/Statistic Problems
Determine the temperature of the fluid by using a heat balance.
Calculate the logarithmic mean temperature difference (∆Tm,l og ).
Propose a design of the air HEX by proposing a number and size of banks along with a number of tubes and passes as well as the number and size of fins to establish the surface area of the tubes (At ) and fins (A f ).
Calculate the heat transfer coefficient for the stream of propane and air (αp and αa respectively).
Calculate the fin efficiency for heat transfer, and determine the effective heat exchange area AH E X .
Find the minimum overall heat transfer coefficient (Umi n ) and compare with acceptable values
from literature.
Calculate the overall heat transfer coefficient (U ), allowing for fouling factors.
Check pressure drop in both streams, the pressure drop inside the tubes should be no larger than 0.3 bar for propane and should be no larger than 150 Pa for air.
Accept or recalculate the design of the air HEX by suitably varying the parameters.
