We present a two phase airwater nozzle that can be applied to indirect evaporative cooling to improve the heat transfer efficiency of indirect evaporative coolers by improving the uniformity of the water film on the surface of the heat exchanger. The spray characteristics of a nozzle with a fanshaped orifice at various air and water pressure conditions was studied. The spray cone angle, the airwater mass flow rate, and the relationship between the mass flow rate and the airwater pressure ratio were obtained. The best airwater pressure ratio and spray cone angle were also found.