On the basis of research on velocity distribution of ideal flow field

numerical simulation and cold state model test were conducted for typical non-ideal flow field with baffle

elbow and shrinkage. The results show that

the flow field distribution is uniform in front of the throttling element

it is suitable for the flow measurement. While behind the throttle element

the distribution of flow field is extremely non-uniform

the eddy current region and low speed region exist

and the flow field is different and irregularity between and among the throttling elements. The disturbance of flow field is different

the flow velocity in cross-section of non-uniform tube segment is greater than that in the pipeline

close to that in the elbow

and has the maximum deviation from that in the baffle. The flow coefficient of the new type Venture flow measurement is basically stable

and the resistance is small

it is practical for the non-ideal flow field.