Spray Impact

Impact is a measure of the force at which a spray liquid impinges on a surface. Its value depends on the six factors: liquid density, nozzle type, working pressure, flow rate, spray angle and installation distance.

Increasing the fluid pressure increases the overall internal energy of the fluid. How much of this increase in energy is used to atomize the spray and how much is used to increase momentum and impact depends very much on the nozzle being used.

The solid stream nozzles provide more impact than the flat fan nozzle, because the solid stream is concentrating more flow per area than the flat fan nozzle. The flat fan nozzles have a wider spray angle and the spray will provide you with more coverage but will concentrate more flow over a larger concentrated area.

General rules of thumb are that solid stream nozzles are the most efficient at transferring energy into momentum, followed by flat fan nozzles, then hollow cone nozzles, then full cone nozzles. It should be noted that often nozzles will be discussed as being very energy efficient. This often means they are very efficient at using internal fluid energy to atomize the fluid and so in this respect are very inefficient at energy transfer.