Task 1 Heat transfer area inside the vapour generator is a bunch of 51 steel pipes of diameters 32/28 mm (steel heat conduction coeff. is 45 W/(m-K)). This apparatus is working in cross flow regime. From the generator is receiving 100 kg/min of ethanol vapours, which is heated from the liquid at 29C to the boiling temperature 78C. Heating agent is a water steam that during process is cooling down from 152C to 124C. Liquid ethanol specific heat is 2380 J/(kg:K), evaporation heat 842 kJ/kg. Specific heat of water steam is 2000 J/(kg-K). Heat transfer coefficient at the steam side is 12000 W/(m2K), and at the ethanol side is 2800 (W/m2K). Calculate the amount of the heating agent and the necessary length of pipes. Tab. 1. Correction values for the cross flow regime 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0,996 0,994 0,992 0,988 0,984 0,978 0,973 0,961 0,937 0,993 0,988 0,983 0,975 0,967 0,955 0,942 0,919 0,873 0,990 0,983 0,974 0,9620,952 0,935 0,908 0,872 0,810 0,987 0,975 0,962 0,918 0,9350,909 0,873 0,824 0,738 0,984 0,967 0,950 0,935 0,910 0,875 0,832 0,765 0,665 0,980 0,955 0,9350,909 0,877 0,835 0,780 0,698 0,581 0,975 0,942 0,911 0,875 0,832 0,780 0,710 0,614 0,485 0,9610,919 0,872 : 0,824 0,758 0,698 0,614 0,500 0,360 0,928 0,867 0,801 0,738 0,6720,581 0,190 0,360 0,220