What is the diameter of droplets in Schiller and Naumann model for fluid-fluid drag?
 

For fluid-fluid exchange coefficient, the default is the Schiller and Naumann. In this model, there is a parameter named dp. dp is the diameter of the bubbles or droplets of dispersed phase. but, what is the dp? several mm or determined by a formula?

thanks!

i think u can give a estimated value, in my case i set the diameter of bubbles in euler mutiphase method 0.001m.