A single - pass shell and tube counter flow heat exchanger uses waste gas on the shell side to heat a liquid in the tubes. The waste gas enters at a temperature of 400C at a mass flow rate of 40 kg/s; the liquid enters at 100C at a mass flow rate of 3 kg/s. Neglect the thermal resistance of the tube wall and assuming that the velocity of the liquid is not to exceed 1m/s. Calculate: i. ii. iii. Data: - the required number of tubes; the effectiveness of the heat exchanger; the exit temperature of the liquid. tube inside diameter = 10 mm; tube outside = 12.7 mm; tube length = 4 m; Cp of waste gas = 1.04 kJ/kgK; Cp of liquid 1.5 kJ/kgK; p for liquid = 500 kg/m; heat transfer coefficient on the shell side heat transfer coefficient on the tube side = 260 W/mK; 580 W/mK. (77 tubes; 0.358; 207.4C) =