I recently tried an experiment in whirlpooling. I have an 8 gal BK from Morebeer that has the 1/2" MPT coupling for the temperature probe positioned about 4" directly above the drain valve coupling. Since it is well below the top level of the boiled wort I thought I might try using it as an inlet for the input to my pump and connect the output from the pump to the drain valve. To do so I needed to attach a second ball valve to the temperature coupling with a 1/2" nipple so as to block any unwanted drainage from there during the boil.
Using parts from Home Depot (1/2" street 90deg, 1/2" street 45deg, 1/2" MPT compression fitting, and a short approx. 4" long copper pipe) I soldered up a collection fitting that rests at the flowline of the inside of the BK where it can be used to drain the completed boiled wort.
By using it to direct the flow from the pump output it therefore creates a nice swirling effect along the inside bottom edge of the BK thus draining the wort from the upper regions and spilling them back into the lower region. I let it pump this way for about 5-10 minutes then shut the pump off and let the rotating trub settle out. It works beautifully as can be seen in the attached picture and I had a minuscule amount of trub going into the fermentor. The soldered fitting also makes for a very efficient BK drain pickup, all for about $25 including the second ball valve.