Based on the two-dimensional hydrodynamics equations and the real flow boundary condition at the inlet of tube

an improved dissipative model was proposed. Compared with the dissipative model

the improved one taking the speed of flow field into account can describe the effect of tube on measuring dynamic pressure more accurately in wind tunnel test. The experiments in FL-14 wind tunnel also indicated that the improved dissipative model can dramatically reduce the measuring error compared with the dissipative model. The relative error of 534% resulting from the correction via dissipative model decreased to 66% via the improved dissipative model at certain experimental conditions.