Abstract: A method and apparatus for identifying, quantifying and correcting turbine meter errors related to pulsation effects in a gas stream being measured. A turbine meter pulse rate output signal is monitored and abnormal pulse rate modulations in the signal are detected and used to indicate turbine meter measurement errors. The equation used to determine turbine error requires measurements of pulsation intensity over a desired frequency range. Because of the difficulty in measuring pulsation intensity at field sites, meter error is determined directly from rotor speed modulation data. Rotor speed modulation data is obtained and then quantitatively related to pulsation intensity using a rotor response model. Thus, meter error is determined directly from rotor speed modulation data, allowing on-site quantification and correction of errors.

Abstract: An apparatus for determining a square root averaging error for a differential pressure orifice meter while measuring volumetric fluid flow in a closed medium including input circuitry that provides an input signal corresponding to the instantaneous differential pressure measured at the orifice plate and logic circuitry connected to receive the signals from the input circuitry for computing the square root averaging error for the orifice meter over a selected time interval. Also disclosed is an apparatus for measuring volumetric fluid flow in a closed medium that includes input circuitry for providing an input signal corresponding to a differential pressure at an orifice located within the closed medium and logic circuitry connected to receive the input signal, compute a square root of the corresponding differential pressure and provide an output signal corresponding to this square root.

Abstract: Acoustic pulsations in fluid transmission systems such as gas pipelines, engine exhaust systems and compressed air networks are suppressed by an acoustic filter comprising an enlarged pressure vessel with inlet and outlet conduits arranged such that conduit inlet and outlet openings are at the pressure node of standing pressure waves of the pressure vessel length resonant frequency and odd or even harmonics of the fundamental frequency. The inlet and outlet conduit openings are arranged such that the direction of convection flow and acoustic pulsation modulating flow is transverse to the instantaneous particle velocity of fluid resulting from acoustic pulsations existing in or excitable in the pressure vessel. Inlet and outlet conduits preferably open into the pressure vessel in a generally radial direction with respect to the central longitudinal axis of the vessel.

Abstract: A system for electrically simulating the acoustical properties of a fluid transfer system including an electrical circuit for simulating the acoustic properties of fluid piping and an electrical circuit coupled to the fluid piping circuit for electrically simulating the acoustical properties of fluid transfer through at least one cylinder of a reciprocating compressor wherein the reciprocating compressor simulation circuitry includes a variable capacitor that simulates a change of volume and pressure within the compressor by varying the magnitude of capacitance. The system also includes the means for electrically simulating the acoustic properties of a centrifugal compressor including a variable capacitor for simulating flow through the compressor. This system further includes an output circuit for displaying the operational parameters of the system.

Abstract: Disclosed is an analog apparatus for simulating the low frequency pulsations and surge characteristics of centrifugal compressors and pumps and their interaction with piping systems. The apparatus includes a capacitor pump for simulating the pumping action of a centrifugal compressor. Voltages are applied to the input and output of the capacitor pump that are proportional to the section and discharge pressures of the compressor. The capacitor pump is driven electrically to simulate the action of the centrifugal compressor in a piping network.