In this article, the UDF technology in Fluent software is used to simulate three-dimensional flow fields and to obtain various flow parameters. The standard k-ε model and the RNG k-εmodel are both used to calculate the inner flow field of the basal meter, and a comparison of the calculated results between two models shows that RNG k-εmodel is more effective for calculations of the inner flow of rotary wing mechanism. The influence of tip clearance on the characteristics of the basal meter is studied. The influence of the bottom ribs on the heat meter is evaluated by the numerical simulation method. This article also simulates the flow of disturbance located at the inlet of the basal meter, and shows that a swirl located at the front of the basal meter can affect the stability of the heat meter.