At present, there is a common problem that the mixing mode is single and it is difficult to overcome the inherent bottleneck of multiphase mixing. A mixing device combining the advantages of jet entrainment and mixing dispersion was designed and built. In an effort to determine the mixing degree of two phases, the mixing coefficient of gas−liquid charging was measured using the cylinder method with the optimal working parameters. To explore the optimization of the mixing conditions and control mechanism of multiphase materials, the law of gas−liquid shear mixing in the process of multi-force field synergistic change was revealed. Based on the testing of the gas injection capacity under different working conditions and the calculation of the gas−liquid two-phase mixing coefficient, it was concluded that the flow rate was the direct key factor affecting the gas injection capacity. The working speed also had a certain impact on the gas injection capacity. When working at a high speed and high flow rate, the jet beam broke through the cutting barrier and presented a superposition effect. The jet impact assisted the rotation, and the suction performance of the device was significantly improved, which was conducive to the mixing of the gas and liquid phases. According to the test results of the measuring cylinder method, the calculated average inflation volume is 0.01 m3/(m2·min), the inflation uniformity coefficient is 77.51, and the mixing coefficient of the gas and liquid phases is 0.12.