Abstract: A method using a gas reservoir and a critical nozzle for determining physical properties and/or quantities relevant to combustion of gas or gas mixtures, the method includes: flowing a gas or gas mixture under pressure from the gas reservoir through the critical nozzle; measuring pressure drop in the gas reservoir as a function of time; determining a gas property factor (?*), dependent on physical properties of the gas or gas mixture, based on the measured values of the pressure drop; and determining a desired physical property or quantity relevant to combustion based on the gas property factor (?*) through correlation.

Abstract: A method for the combined controlled regulation of fuel gas-oxygen carriers of a gas operated energy converter plant (15), in particular of a fuel cell plant, is provided in which the mass or volume through flow of the fuel gas (1) and/or of the oxygen carrier (2) is detected in order to regulate the mixing ratio (r) of fuel gas to oxygen carrier. In the method at least two physical parameters of the fuel gas are additionally determined using a micro thermal sensor (3.1, 3.2), for example, the mass flow and/or volume through flow of the fuel gas and the thermal conductivity or thermal capacity of the fuel gas are determined and a desired value for the mixing ratio is determined from the physical parameters which depends on the fuel gas or on the composition of the fuel gas, and which desired value is used for the regulation of the mixing ratio.

Abstract: A method in which a gas property (Q) is determined by correlation from physical measuring quantities (?j) of the gas mixtures. In the method, the physical measuring quantities are combined into a sensor output (Sout) by making use of a sensor output function (ƒ), wherein the sensor output function is determined in such a way that a group of gas mixtures can be separated from a set of gas mixtures for which the gas property (Q) is determined, within which the correlation between the sensor output (Sout) and the desired gas property (Q) is better than in the entire set.

Abstract: A method and a measuring apparatus for determining specific quantities for the gas quality in which the gas or gas mixture flows through an ultrasonic flow sensor as well as through a microthermal sensor, and the former is used for determining the sound and flow velocity and the latter for determining the thermal conductivity and the thermal capacity of the gas or gas mixture. The sound velocity, the thermal conductivity and the thermal capacity are subsequently used for the correlation of the specific quantities for the gas quality.

Abstract: A method using a gas reservoir and a critical nozzle for determining physical properties and/or quantities relevant to combustion of gas or gas mixtures, the method includes: flowing a gas or gas mixture under pressure from the gas reservoir through the critical nozzle; measuring pressure drop in the gas reservoir as a function of time; determining a gas property factor (?*), dependent on physical properties of the gas or gas mixture, based on the measured values of the pressure drop; and determining a desired physical property or quantity relevant to combustion based on the gas property factor (?*) through correlation.

Abstract: A method to determine a physical property or a quantity of gas related to combustion including: flowing a gas from a reservoir through a critical nozzle and past a microthermal sensor wherein the mass flow of the gas through the critical nozzle is the same as the mass flow through the microthermal sensor; measuring the pressure drop in the reservoir as a function of time; deriving a first gas property factor based on a time constant of the pressure drop; determining a second gas property factor which depends from a flow signal generated by the microthermal sensor; determining a thermal conductivity of the gas; and determining the physical property or quantity based on a correlation between the physical property or quantity, and the first and/or second gas property factors and the thermal conductivity.

Abstract: A method in which a gas property (Q) is determined by correlation from physical measuring quantities (?j) of the gas mixtures. In the method, the physical measuring quantities are combined into a sensor output (Sout) by making use of a sensor output function (ƒ), wherein the sensor output function is determined in such a way that a group of gas mixtures can be separated from a set of gas mixtures for which the gas property (Q) is determined, within which the correlation between the sensor output (Sout) and the desired gas property (Q) is better than in the entire set.

Abstract: A method for determining physical properties of combustion including: flowing a gas a critical nozzle and past a microthermal sensor wherein the mass flow of the gas through the critical nozzle is the same as the mass flow through the microthermal sensor; measuring the pressure drop in a reservoir of gas flowing to the nozzle; determining a first gas property factor based on the measured pressure drop; determining a second gas property factor based on a flow signal generated by the microthermal sensor; determining a thermal conductivity of the gas using the microthermal sensor; and determining a physical property of the combustion based on a correlation of the first and/or second gas property factors and the thermal conductivity.

Abstract: A method and a measuring apparatus for determining specific quantities for the gas quality in which the gas or gas mixture flows through an ultrasonic flow sensor as well as through a microthermal sensor, and the former is used for determining the sound and flow velocity and the latter for determining the thermal conductivity and the thermal capacity of the gas or gas mixture. The sound velocity, the thermal conductivity and the thermal capacity are subsequently used for the correlation of the specific quantities for the gas quality.

Abstract: A method for the combined controlled regulation of fuel gas-oxygen carriers of a gas operated energy converter plant (15), in particular of a fuel cell plant, is provided in which the mass or volume through flow of the fuel gas (1) and/or of the oxygen carrier (2) is detected in order to regulate the mixing ratio (r) of fuel gas to oxygen carrier. In the method at least two physical parameters of the fuel gas are additionally determined using a micro thermal sensor (3.1, 3.2), for example, the mass flow and/or volume through flow of the fuel gas and the thermal conductivity or thermal capacity of the fuel gas are determined and a desired value for the mixing ratio is determined from the physical parameters which depends on the fuel gas or on the composition of the fuel gas, and which desired value is used for the regulation of the mixing ratio.

Abstract: A method for determining physical properties of combustion including: flowing a gas a critical nozzle and past a microthermal sensor wherein the mass flow of the gas through the critical nozzle is the same as the mass flow through the microthermal sensor; measuring the pressure drop in a reservoir of gas flowing to the nozzle; determining a first gas property factor based on the measured pressure drop; determining a second gas property factor based on a flow signal generated by the microthermal sensor; determining a thermal conductivity of the gas using the microthermal sensor; and determining a physical property of the combustion based on a correlation of the first and/or second gas property factors and the thermal conductivity.

Abstract: A method for correcting offset drift effects of a thermal measurement device (10) which comprises at least one temperature sensor (15a, 15b) arranged at a defined distance from a heating device (12) for a fluid to be measured, for measuring at least one measurement variable describing the temperature and/or temperature profile during operation of the heating device (12), in which a reference measured value (35) is measured at a reference time in a first measurement of the measurement variable with the heating device (12) turned off, in which a drift measured value (36) is measured at at least one later time in a second measurement of the measurement variable with the heating device (12) turned off, and in which a drift correction is carried out during the measurement by using the heating device (12) on the basis of a difference between the drift measured value (36) and the reference measured value (35).

Abstract: Described is a method and a device for more accurate measurement of a gas supply with a gas meter. A consumption-weighted correction factor is determined by weight averaging of a sensor error factor of the gas meter with a consumption profile characteristic of the gas supply location and the measuring signal is converted using the correction factor. Embodiments relate inter alia to: operation of the gas meter as volume, mass or energy meter; formulae for determining the correction factor with sensor error factors and consumption profiles relative to volume, mass or energy; and measuring signal correction in the case of a non-registering or registering gas meter. Advantages are inter alia: subsequent customer-specific measuring signal correction; no additional measuring complexity; and improved measuring accuracy, in particular improved energy measurement by means of compensation for inherent deviations of the energy signal in the vase of heat value variations.

Abstract: Described is a method and a device for more accurate measurement of a gas supply with a gas meter. A consumption-weighted correction factor is determined by weighted averaging of a sensor error factor of the gas meter with a consumption profile characteristic of the gas supply location and the measuring signal is converted into a corrected consumption or output value with the correction factor. Embodiments relate inter alia to: operation of the gas meter as volume, mass or energy meter; formulae for determining the correction factor with sensor error factors and consumption profiles relative to volume, mass or energy; and measuring signal correction in the case of a non-registering or registering gas meter.

Abstract: The invention relates to a process and a device for thermal measuring the flow rate (v) of a fluid (3). In conventional thermal sensors the heating power P is supplied in the form of rectangular pulses. According to the invention, the sensor means (1b) are supplied by a heating control (2b) with non-constant heating pulses having a sublinear build-up dynamics P(t). Thereby, a nonlinear behaviour of the threshold value time (tS), until a threshold value temperature (Tm) is reached, as a function of the flow rate (v) can at least partially be compensated. Embodiments concern inter alia a build-up dynamics P(t) proportional to tm and/or to a time-independent amplitude factor (1+RS/RI)?1, wherein m is a Reynolds-number-dependent exponent and RS, RI are thermal transfer resistances. The advantages are an improved precision, a shorter measuring time and an enlarged measuring range for the flow rate v.

Abstract: A gas meter for determining a gas mixture consumption is revealed which determines sensor signal values proportional to a flow rate, this gas meter being calibrated as an energy measuring unit. The calibration is based on a basic gas mixture. During the measurement of the gas consumption, a measured energy consumption value is multiplied by a correction factor which takes account, at least approximately, of the calorific value of a supplied gas mixture, this calorific value being determined by an external unit. By this means, it is possible, using a simple and cost-efficient gas meter, to determine the effective supplied energy and to bill costs according to the supply.

Abstract: The invention relates to a process and a device for thermal measuring the flow rate (v) of a fluid (3). In conventional thermal sensors the heating power P is supplied in the form of rectangular pulses. According to the invention, the sensor means (1b) are supplied by a heating control (2b) with non-constant heating pulses having a sublinear build-up dynamics P(t). Thereby, a nonlinear behaviour of the threshold value time (tS), until a threshold value temperature (Tm) is reached, as a function of the flow rate (v) can at least partially be compensated. Embodiments concern inter alia a build-up dynamics P(t) proportional to tm and/or to a time-independent amplitude factor (1+RS/RI)?1, wherein m is a Reynolds-number-dependent exponent and RS, Rl are thermal transfer resistances. The advantages are an improved precision, a shorter measuring time and an enlarged measuring range for the flow rate v.

Abstract: A proximity sensor, in particular a proximity switch is described. A component that pertains to a system variable and is independent from the material of a trigger or target is elected and transformed into a non-periodic signal that depends upon the distance of the trigger. The trigger of a proximity sensor can thus be exchanged randomly without requiring subsequent adjustments. The impedance of an oscillation circuit which pertains to the proximity sensor, the impedance of an oscillation circuit coil, the amplitude of the oscillation circuit signal or a voltage divider ratio between the oscillation circuit and the additional resistance can be used s system variables for instance.

Abstract: A gas meter for determining a gas mixture consumption is revealed which determines sensor signal values proportional to a flow rate, this gas meter being calibrated as an energy measuring unit. The calibration is based on a basic gas mixture. During the measurement of the gas consumption, a measured energy consumption value is multiplied by a correction factor which takes account, at least approximately, of the calorific value of a supplied gas mixture, this calorific value being determined by an external unit. By this means, it is possible, using a simple and cost-efficient gas meter, to determine the effective supplied energy and to bill costs according to the supply.

Abstract: A photoacoustic effect is used in order to measure a flow rate of a flowing medium (M), in particular of natural gas. A light emitter (1) is used to produce in the medium (M) a sound wave (S) which is transmitted by the medium (M) and detected by a sound detector (2). The light emitter (1) is less exposed to the medium (M) than a diaphragm such as used in the ultrasonic method.