(Solved): A counterflow shell and tube heat exchanger is used to recover the waste energy from the hot oil to ...

A counterflow shell and tube heat exchanger is used to recover the waste energy from the hot oil to heat water at the rate of \( 11000 \mathrm{~kg} / \mathrm{hr} \). The steam enters the heat exchanger at \( 180^{\circ} \mathrm{C} \) and leaves at \( 120^{\circ} \mathrm{C} \). The inlet and exit temperatures of water are \( 40^{\circ} \mathrm{C} \) and \( 90^{\circ} \mathrm{C} \) respectively. If the overall heat transfer coefficient from steam to water is \( 814 \mathrm{~W} / \mathrm{m}^{2} \) \( \mathrm{K} \), calculate: \( \left(\mathrm{cp}\right. \) oil \( \left.=2.5 \mathrm{KJ} / \mathrm{Kg} .{ }^{\circ} \mathrm{c}, \mathrm{cp}_{\text {water }}=4.18 \mathrm{KJ} / \mathrm{kg} \cdot \mathrm{k}\right) \) 1. The heat transfer area? 2. Minimum flow rate of water in \( \mathrm{kg} / \mathrm{min} \) ? 3. The effectiveness of the heat exchanger?