i am attempting to do a shell and tube heat exchanger thermal design where i raise the temperature of steam from 200 to 500 using flue gas. how do I estimate overall transfer coefficient? I am aware I have to use Perrys handbook and R sinnot's chemical engineering design. However I do not how, I have looked at the graph and the tables but I do not understand how i can get my answer as flue gas and steam are not specified anywhere. Please help.