Abstract: The existing dust generating device can not meet the research needs of migration laws, dust distribution, settlement laws of air curtain dust control effect in laboratory, a swirl diffused dust generating device with spiral dust spinning is designed. In this paper, the direction of the dust outlet is designed to be 30°, 60°and 90°. The dust emission range of the dust generating device is increased, and the dust generating device with a single direction is made up. Evenly arranged around the rotating dust generator, 4 dust diffused blades offer power for dust movement, and increase the time of dust movement in space. The test results show that: four kinds of dust tests proved that the design of the rotary expansion device can meet the research needs of migration laws, dust distribution, settlement laws of air curtain dust control effect in laboratory, and offer the dust source for lab simulation research on environmental test of dust.