| 摘要 |
FIELD: physics. ^ SUBSTANCE: method of determining parameters of a gaseous medium involves placing an electrical measuring transducer into the gaseous medium, the detecting element of the transducer being made from electroconductive material whose resistance depends on temperature. Direct current is then passed through the sensor and the time interval is measured. The method employs an electrical measuring transducer which has at least one set of sensors, including at least one moisture sensor and/or pressure and vacuum sensor and/or flow sensor, the detecting element of each sensor being made from material with high thermal resistance coefficient. Before passing direct current through the sensor, pulse current is first passed, the pulse duration of which is selected such that temperature of said sensor does not change over the passage time of the pulse. Said time interval is defined as time from the beginning of passing direct current to the moment the potential drop across the sensor equals the sum of the following voltages: voltage across the sensor, which is established when pulsed current is passed through the sensor, and voltage, the value of which, together with the value of said direct current, is selected based on the condition for providing optimum or close to optimum sensitivity of the sensor. Temperature of said sensor at the moment or after temperature of the sensor coincides with temperature of the gaseous medium is determined, and its value is determined from calibration curves or tables using the value of the measured time interval and the value of temperature of the gaseous medium for each investigated parameter of the gaseous medium. ^ EFFECT: high accuracy and wide range of use and functional capabilities of the method and apparatus, simple design of the apparatus. ^ 14 cl, 3 dwg |
