The technical solution for measurement of the energy value of natural gas on the basis of variable pressure-drop flowmeters, which are additionally provided with a hot-wire transducers is proposed. The functional circuit and operation algorithm of the proposed measurer of the energy value of natural gas are given. The metrological model for determining the energy value of natural gas and an algorithm for calculating the uncertainty are discussed on the basis of the theory of uncertainty in the measurements. The models of the uncertainties of the constituent components in determining of the energy value of natural gas are analyzed: flow rate measurement model, the model for determining the calorific value, the model of the measured gas flow rate translation to standard conditions.
natural gas, energy value, flow rate, calorific value, constriction device, hot-wire transducer, standard uncertainty