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I am an undergraduate student of mechanical engineering making a thesis about how an induced draft fan works on a cooling tower. I would like you to explain to me whether I can apply the packed tower equations (Constant of Henry, L'/G' ratio, pressure drops,diffusivities, Shulmann correlation, etc) in my design of the cooling tower?. Could you provide the correlation/equation of L/G vs KaV/L without resort to the diagram.  How should I apply the value of KaV/L in my design?.

Let's see if I can clear this up for you.   If you are going to design a cooling tower, forget the packed tower correlations, they're very different
towers.  Packed towers rely on increased surface area for mass transfer while cooling towers rely more on air velocity and contact time for mass transfer.  Designing a cooling tower in an industrial setting (as described by my article) is different than doing the actual theory of the design.  First, you have to answer the following questions:

1.  What is the highest web bulb temperature for the geography? (for example 75 degrees F)
2.  How close to the wet bulb temperature do you want to cool the water?
        Realistically, the best you can hope for is to cool water to 5 deg F
        above the wet bulb, in our case 80 degrees F.   The closer to the wet bulb
        temp, the larger the tower.
3.  What is the flowrate and the inlet temp of the water?
        This will determine how much heat you need to remove.

The amount of heat to be removed will determine the tower height (contact time with air while water falls) and air velocity through the tower cell
(how quickly heat is removed while the water falls).  Typical design L/G ratios range from 0.75 to 1.50.  Once the previous questions are answered, the theoretical KaV/L should be calculated via the numerical integration equation shown in "Cooling Towers: Design and Operation Considerations" on the website at www.cheresources.com.  Then it is necessary to design the cooling tower fill and air distribution to meet the KaV/L value.   Companies that manufacture cooling towers usually have standard towers that they manufacture (as opposed to custom towers).  You can see some standards at:  http://www.atdgc.com/ATD.htm Each one of these towers has a maximum L/G ratio associated with it.  I suspect that you're interested in bridging the gap between the L/G ratio and the geometric construction.  Since the L/G ratio is always supplied by the cooling tower manufacturer, I don't know how they arrive at it.  I suspect it a long history of experience and trial-and-error, but I guess they could have correlations to determine this.  You may be able to get some of these correlations from the cooling tower expert at:
http://www.coolingtower.com/barticle.html.    He will send you any of the articles listed there free of charge or you could email him.  I think he would be a good resource.   Good Luck on your project.