Heat and Mass Transfer

In a vertical tube single effect evaporator, the boiling film coefficient inside the tubes is 1350 W m⁻² K⁻¹. Steam condensation film coefficient outside is 7500 W m⁻² K⁻¹. Thermal conductivity of 20 tubes made of SS 304 is 16 W m⁻¹ K⁻¹. The vertical tubes are 4.3 m long and are of 25 mm ID and 27 mm OD, maintaining a steady 15 °C temperature difference across the tube walls. Assume no boiling point rise, no heat losses, the feed enters the evaporator at the boiling point and the latent heat of vaporization of water is 2346.3 kJ kg⁻¹. Total water evaporation rate from the evaporator bundle of tubes in kg h⁻¹ will be __________.