I am running a numerical analysis having water flow through orifices. Can anyone assist, or recommend papers describing the factors affecting the coefficient of discharge. Does it change significantly with the hole diameter or the hydraulic head?
regarding fully submerged orfices on a sharp vertical wall, the diameter slightly influences the discharge coefficient. Here you can find some experimental results for both free and submerged outflows.
Bos, M. G. (1989). Discharge measurement structures.