An inertial particle separator with scavenge scroll was numerically studied to obtain its flow structure and scavenge efficiency performance characteristics.Results indicate that the flow fields at the top and bottom of the scavenge path are not smooth.Thus

the gas from the circular inlet can not flow into the scavenge scroll equably.When the bypass rate is 19%

the total pressure recovery coefficient of the core flow is 0.982;AC coarse and C-spec separator efficiencies are 64.8% and 76.6%

respectively.The flow structure and performance characteristics of the inertial particle separator are improved

and especially the vortical structures in scavenge scroll are of advantage to sand separating when the flow divider is added to the top of the scavenge scroll.With the same bypass rate

AC coarse and C-spec separation efficiencies increase 18.1% and 20.9%

respectively.Besides

the total pressure recovery coefficient of the core flow does not decrease much.