Experimental and numerical study on a novel thermal mass flowmeter that is insensitive to radial flow velocity distribution

A novel thermal mass flowmeter (TMF) is proposed by improving the composition and structure of the probe in this study. An experimental setup was developed to compare the effects of installation angles on the measure-ment characteristics of the novel and traditional TMF (flow velocity range of 1.0-8.0 m/s), and three-dimensional numerical models were established to compare the effects of axial positions and insertion depths on the measurement characteristics of novel and traditional TMF (flow velocity range of 0.05-8.0 m/s). The experimental results show that when the installation angle changes from 0 degrees to 90 degrees, the maximum power vari-ation of traditional TMF is 16.5%, while that of the novel TMF is only 0.6%. The simulation results show that when the axial position changes from 9 to 1 m, the maximum power variation of traditional TMF is 11.5%, while that of the novel TMF is only 3.8%. When the insertion depth of the velocity sensor translates from the pipe center to 0.10 m upward, the maximum power variation of traditional TMF is 91.6%. The novel TMF is installed by thread or flange compression, with a fixed and unique insertion depth of D/2, there is no change in the insertion depth during measurement. In conclusion, the effect of the flow velocity distribution on the mea-surement characteristics is significantly reduced in the novel TMF compared to the traditional TMF, the mea-surement results are more accurate.