Hi, Please help anyone. The furnace shell will be cooled using spray cooling along the outside wall surface from a reservoir tank and then the water is collected below through troughs. I need to calculate the temp of the water down the shell when collected if it needs extra cooling as it is pumped back to the reservoir. Knowns; 1) 2 mm water film on shell surface 2) Dry bulb temp = Max 50 / Min 6 D.C. 3) Wet bulb temp = 28 D.C. 4) Wind velocity = 50 m/s I dont know where to begin, please send me in the right direction, very rusty in heat transfer. Thanks!