5.45 Normal heptane is flowing in the shell of a STHX at a rate of 400,000 lbm/h and an average temperature of 130°F. The shell has a diameter of 27 in. and a length of 16 ft. The tubes in the heat exchanger are ¾-in. 15 BWG tubes on a 1-in. triangular pitch. The purpose of this problem is to investigate how the number of baffles impacts the heat transfer and the pressure drop on the shell side of the heat exchanger. Calculate the shell-side convective heat transfer coefficient and pressure drop for the case where the heat exchanger has 10 baffles. Repeat the calculation for 20 baffles. Then determine the following:

a. Ratio of the shell-side convective heat transfer coefficient for the 20-baffle heat exchanger to the 10-baffle heat exchanger.

b. Ratio of the shell-side pressure drop for the 20-baffle heat exchanger to the 10-baffle heat exchanger.

c. If the optimum baffle spacing is somewhere between 0.4Ds and 0.6Ds , how many baffles would you recommend for this heat exchanger? What are the values of the shell-side convective heat transfer coefficient and pressure drop for the number of baffles you recommended?