Experimental investigation and CFD simulation of multiphase flow behavior in air reverse circulation drilling

•CFD method and a novel experimental device were used to study the physics of multiphase flow associated with the cleaning process.•Air influx was measured under the different conditions of ROP, cuttings diameter, and water yield.•The influence of ROP, cuttings diameter, and water yield on air influx was revealed.•Cuttings velocity and pressure drop could be influenced by ROP, cuttings diameter, and water yield.