I am trying to analyse the relationship of flow rate rate through a simplex nozzle. Here is the situations. Fuel = Kerosene I have a simplex nozzle for injection. And there is a fuel pipe before the nozzle [obviously :P] The flow rate in the pipe is controlled by varying the velocity of fuel in the pipes just before the nozzle. [its is already decided on how flow rate will be varied by increasing/decreasing velocity]. The pressure is always constant in the pipe, only the velocity of fuel flow varies to change fuel flow rate. Ok so i read that flow rate through the atomizer is function of square root of pressure difference between the atomizer and chamber. [correct me if this is wrong] 1) But is it function of static pressure or total pressure? 2) So increasing flow rate by increasing velocity WHILST keeping pressure constant increase the flow rate in the atomizer? If there's something unclear, i will try explaining with more details.