Shell and Tube Heat Exchanger Example

Two simple water $-$ water heat exchangers $($both fluids are water$)$: concurrent flow one and countercurrent flow one. $U$ for both heat exchangers $=4\mathrm{.}651Bt\frac{u}{h*f{t}^2*F}.Cp=1\mathrm{.}0Bt\frac{u}{l}bF.$

The mass flow rate of center tube inlet is $1,000l\frac{b}{h}$ and temperature is $200F.$ The outlet temperature is $150F.$

The mass flow rate of shell inlet is $2,000l\frac{b}{h}$ and temperature is $50F.$ The outlet temperature is $75F.$

Calculate the area required for both heat exchangers.