Abstract: A three-dimensional steady simulation of the flow in the four-branch pipe of a controlled cooling device was carried out by the numerical simulation calculation method of finite element coupling field. The effect of nozzle pipe diameter, nozzle pipe height, branch pipe diameter, and inlet velocity on the flux uniformity at the nozzle pipe outlet was analyzed. The result of simulation show that nozzle pipe diameter, branch pipe diameter and inlet velocity have a great influence on the flux uniformity at the nozzle pipe outlet, but nozzle pipe height has a little influence on it.