ENFLOW: Energy flow metering of natural and biogas for residential applications

Purpose and goal

World experience shows that both gas consumers and suppliers would highly benefit from the possibility to conduct energy flow metering at the consumption site using one instrument capable of both gas flow and calorific value measurement. The purpose of the project was to develop and validate the measurement technology, calculating algorithm, and instrument prototype that allows estimating the calorific value based on the ultrasonic measurement accomplished by the typical residential ultrasonic gas flow meter.

Expected results and effects

Within the project, we have developed the calculation algorithm that allows estimating the calorific value of natural gas based on the measurements of physical properties of natural gas: speed of sound and sound attenuation. These properties could be obtained during typical gas flow measurement accomplished by a residential ultrasonic gas flow meter operating at a specified high frequency of ultrasound 500kHz and 1MHz. The performance of the algorithm is highly dependent on gas composition and acceptable performance was achieved for limited gas groups applications.

Planned approach and implementation

The calculation algorithm is based on a machine learning model built on experimentally obtained datasets. The experimental investigation consisted of simulation and analysis of the vast number of gas compositions representing realistic natural and biogas, using a specially created gas mixing station, developed sensor arrays, and reference gas chromatography. In cooperation with German partners, the test setup for measurement speed of sound and sound attenuation at various frequencies was developed and tested during an extensive experimental campaign.