DEVELOPMENT OF A CORRELATOR FOR FLOW MEASUREMENT IN PIPELINES USING GAMMA RADIATION AND CROSS-CORRELATION FUNCTION

Resumo

The aim of this report was to develop an alternative flow rate measurement method with low uncertainty for low sampling frequency systems using radiotracers and the Cross-Correlation function. The experimental tests were carried out on a closed water transport line built in Polyvinyl Chloride (PVC) with 30 m length. The radiotracer used was Na⁸²Br injected as a rapid pulse with volume of 3.0 ml (3 MBq) per test. Data acquisitions were made with a sampling rate ranging between 20 Hz and 1 kHz. A measurement correlator (hardware and software) was developed using special mathematical methods, such as: Savitzky-Golay filtering and Lagrange interpolation to reduce the uncertainty of the flow rate measurement. The correlator was tested in a water flow rate range of 200 L/h to 800 L/h with an uncertainty of 2.0% at a flow rate of 200 L/h.