If you want to do that, I am afraid I don't have the know-how to help you step by step. However, I think you should try and look for graduate papers on the matter, they are usually very helpful when you take the time to read and understand them.
I can recommend you to start easy and then...
I am not an expert, but if you are strictly interested in the amount of energy, you may want to use the Work-Energy method, which is what you referred to when talking about Ke. The method is quite simple: you evaluate the different types of energy (elastic, potential and kinetic) at a point A...
Ok, so I am trying to build myself a small water tank (about 1 L) with 2 tubes coming from the top. The first one goes all the way down to the bottom (thus in the water) and acts as the outtake. The second one is an air intake where the air pressure is regulated, say 5 psi. Now, I want to be...