The invention provides a method for designing and selecting a model based on a LABVIEW throttling device, relates to the field of instruments and control, and aims to solve the problems of difficulty in
model selection checking calculation and low accuracy of the throttling device in flow measurement of gases such as water, steam and
natural gas in a chemical device. The method depends on an
LABVIEW software platform, comprises eight
model selection calculation sub-modules, covers various throttling devices such as a
nozzle, a standard pore plate and a classic Venturi tube and different pressure taking
modes, and can process flow measurement scenes of gas such as steam, water and
natural gas in a targeted manner. Each sub-module comprises a main program, six types of calculation sub-programs and an
intelligent verification sub-program. And the
intelligent verification subprogram is combined with a rule judgment engine to identify abnormal input and perform graded early warning. And the main program calls each subprogram to execute calculation, outputs key results such as the inner
diameter of the pipeline, the Reynolds number and the
differential pressure, and can perform checking calculation on a calculation book of a manufacturer and generate a comparison report. According to the method, the deviation between a steam
nozzle and pore plate
model selection calculation result and manufacturer data is smaller than 0.01%, and the model selection accuracy and efficiency are remarkably improved.