title: Absolute measurement of low gas flow by means of the spectral analysis of the thermal wave.
abstract: A new technique has been developed for determination of the very low gas flow velocity by means of the spectral analysis of the thermal waves. It is assumed that the transmitter signal is made of sine waves. By employing the Fourier analysis of the detector signals, the phase shifts of the relevant harmonic component of the frequency function were determined. The flow velocity has been obtained by a nonlinear regression analysis of the measured phase shifts values. This method allows for the flow of gas to be measured in a range from 5 to 500 cm/s.
authors: Strata Mechanics Research Institute, Polish Academy of Sciences, Reymonta 27, 30-059 Cracow, Poland.
authors: A
authors: A
authors: Rachalski