An experimental study on the change of drop size distribution with spray interaction in a condensable environment was carried out. Experiments were performed by collecting drops of a twin spray using the immersion sampling technique.
It was found that, in the twin spray, larger numbers of small drops are collected throughout the spraying region due to the increase of entrainment velocity of ambient steam compared with the case of simple superposition of each single spray. However, in the overlapped portion of the twin spray, the drop size distribution was changed also due to the collision of large drops.
As a result, in multiple spray system, drop size distribution can not be well predicted simply by superposing the results of measurements of drop size distribution of each single spray.