035 kgs of styrene is to be cooled from 90C to 55C in the an

0.35 kg/s of styrene is to be cooled from 90°C to 55°C in the annulus of a double pipe heat
exchanger. The two steel pipes are 1¼ in and 2 in nominal size. A cooling stream of water, in the
inner tube, is available at a temperature of 27°C. The inside heat transfer coefficient is given and
it is 1.0 kW/m2.°C. Calculate the mass flowrate of water required if the outlet temperature of
water is 45°C, LMTD, the overall heat transfer coefficient based on outside surface, and total
surface area of the exchanger. If the effective exchanger length is not to exceed 8 ft, calculate the
number of tubes required. Use both the Dittus-Boelter equation and Second Petukhov equation
for your calculations. Also, do the calculations for both cocurrent flow and countercurrent flow.
Use reliable literature source for the physical properties.

Solution

The answer of following question is as follows .

The required of number of tubes are 7 .

The mass flow rate 89mm3/sec .