Data correction for pressure transmission lines using discrete time series models

A technique was demonstrated which can allow for online correction of the unsteady pressure signals transmitted through small-diameter pressure transmission lines. This time-domain technique involves the parameterization of an invertible, autoregressive moving average model for the pressure transmission line system. Applications of the technique to long slender transmission lines, 60 in (1.5 m) long, are reported. The digital filters developed from time series data, obtained by using random inputs to the pressure transmission system, were used to predict system input using measured output. The method was applied to the measurement of unsteady surface pressures on a circular cylinder.