A method for determining an inferential relationship between an inferred energy content and at least one measured quantity is disclosed. The inferential relationship yields an inferred energy content. The method uses a computer (200) having a processor (210) configured to execute commands based on data stored in a memory (220), the processor (210) implementing steps of an inference module (204) stored in the memory (220), the method comprising a step of determining, by the inference module (204) the inferential relationship by analyzing a relationship between known measurements of at least one measured energy content of at least one fluid and at least one corresponding measured value of a same type as the at least one measured quantity wherein the inferential relationship has a density term (B), wherein one of the at least one measured quantity is a measured density (ρ) and the density term (B) has an inverse density (1/ρ), the density term (B) representing an inverse relationship between density (ρ) and the inferred energy content, and wherein the measured density (ρ) is not a density of air (ρ.sub.air).

The application provides an electrical system with online sampling and check function and its check method for high-voltage and medium-voltage electrical equipment, including electrical equipment, gas density relay, gas density sensor, valve, pressure regulating mechanism, online check contact signal sampling unit and intelligent control unit. The pressure is increased or decreased by the pressure regulating mechanism to enable the contact action of the gas density relay of electrical equipment. The contact action is transmitted to the intelligent control unit through the online check contact signal sampling unit. The intelligent control unit detects the alarm and/or blocking contact signal operating value and/or return value according to the density value of the contact action; the check of the gas density relay can be completed without maintenance personnel on site, which greatly improves the reliability of the power grid and the work efficiency, and reduces the O&M cost. At the same time, it also realizes the mutual self-inspection between gas density relay and gas density sensor, and further realizes the maintenance-free.

A measuring device for determining the density, the mass flow and/or the viscosity of a gas-charged liquid includes an oscillator, having a media-conducting measuring tube and two vibrational modes having media-density-dependent natural frequencies; an exciter for exciting the two vibrational modes; a vibrational sensor for detecting vibrations of the oscillator; and an operating and evaluating circuit to apply an excitation signal to the exciter, detect signals of the vibration sensor, determine current values of the natural frequencies of the two vibrational modes of the oscillator and fluctuations of the natural frequencies. The operating and evaluating circuit is designed to determine a first media state value, wherein the operating and evaluating circuit is furthermore designed to determine a second media state value which represents a gas charge of the medium.

The technical result consists in increased accuracy of density measurements of a liquid using a simplified sensor configuration. The sensor for a vibration densimeter comprises a hollow cylindrical body on one end face of which is hermetically attached a metal membrane. To the inner side of the membrane is attached a piezoelectric element, and to the outer side of the membrane is attached a mechanical vibration transducer, which is made in the form of a tuning fork, to which a hollow cylindrical resonator is attached in the longitudinal direction. Moreover, the base of the tuning fork is attached to the membrane, and the teeth of the tuning fork are attached to an end face of the hollow cylindrical resonator.

An oscillator for density measurement of a liquid, including a counter mass and a container for the liquid. The oscillator is made of metal and the container has two identical resonator tubes, which are clamped into the counter mass in parallel to each other, and a connecting tube connecting the resonator tubes. The resonator tubes can be set into a resonance oscillation in which a common centre of gravity of the resonator tubes remains at rest during the resonance oscillation. The oscillator also includes a web located between the counter mass and the connecting tube, which web spaces the resonator tubes from each other in such a way that the lengths (L) of the resonator tubes enclosed between the counter mass and the web can be set into a diametrically opposite oscillation on the basis of which the density of the liquid located in the oscillator can be determined.

A flow measuring device capable of measuring at least parameters of a multiphase flow and to quantify an effect of decoupling on an interpretation of the parameters based on at least one characteristic of the multiphase fluid is disclosed. The flow measuring system includes various augmentations and enhancements to a Coriolis meter. The flow measuring system is capable of determining decoupling parameters that can be used to improve the output of a Coriolis meter. A method of retrofitting a Coriolis meter is also disclosed.

The modification method for the gas density relay, the gas density relay with the online self-check function and the check method thereof provided by this application are used for high-voltage and medium-voltage electrical equipment, including a gas density relay body, a gas density detection sensor, a temperature regulating mechanism, an online check contact signal sampling unit and an intelligent control unit. Regulate temperature rise and fall of the temperature compensation element of the gas density relay body through the temperature regulating mechanism, which leads to a contact action of the gas density relay body, the contact action is transferred to the intelligent control unit through the online check contact signal sampling unit, and the intelligent control unit detects the operating value and/or return value of the contact signal of the gas density relay body based on the density value at the time of contact action. The gas density relay check can be completed without maintainer at the site, so as to realize free maintenance, greatly improve the reliability of power grid, increase work efficiency and reduce the cost.

A device for determining and/or monitoring at least one process variable of a medium includes a mechanically vibratable unit, a drive/receiver unit and an electronic unit. The drive/receiver unit is designed to excite the mechanically vibratable unit to produce mechanical vibrations using an electrical excitation signal, and to receive the mechanical vibrations of the mechanically vibratable unit and convert them into an electrical reception signal. The electronics unit is designed to generate the excitation signal on the basis of the received signal, to set a frequency of the excitation signal in such a way that there is a predeterminable phase shift between the excitation signal and the received signal, and to determine the at least one process variable on the basis of the received signal, the mechanically vibratable unit comprising a diaphragm, and a surface of the diaphragm facing the process being curved.

A digital densitometer for a fluid gauging system includes a frequency detection device configured to be disposed within a fluid tank, wherein a frequency detected by the frequency detection device is indicative of a density of a fluid within the fluid tank, frequency detection circuitry configured to obtain the frequency from the frequency detection device and output the frequency in a digital form, and an interface for digital communication with an electronic controller, the digital communication comprising transmission of the digital form of the frequency for the electronic controller.

A flow sensor includes a flow tube in a form of a tube and a support cast around the flow tube. The support clamps the flow tube and the flow tube extends through the support. The flow sensor is formed by placing the flow tube in a tube cavity of a casting mold and pouring or injecting a liquid resin into a support cavity of the casting mold. The support is formed around the flow tube from solidifying the liquid resin in the support cavity of the casting mold. A temperature of the casting mold during formation of the support does not exceed a threshold temperature to avoid deformation of the flow tube. The flow sensor can also include at least one memory chip that stores calibration information associated with the flow sensor and connectors that allows a controller to read the calibration information from the memory chip.