LT3170B - Method for measuring the mass flow of fluid and gas - Google Patents

Abstract

This method is used for measuring the amount of fluid and gas, estimating the consumption of gaseous and fluid fuel.The measurement method involves the heating and measuring of the average flow. Before measuring and heating, the part of the flow is marked off for measuring by a fixed proportion. Then it is heated by an electric current with stabilized voltage till it reaches the constant temperature difference. The strength of the electric current is measured, and the whole mass amount is estimated according to the formula F = C I, where C = 1,163 U (K + 1). Here 1,163 is the proportion between the units of electricity and thermal energy power, U is the stabilized electric current tension, K is the coefficient of the flow division proportion, and I is the strength of the electric current.

Description

The invention relates to gas and liquid volume measurement.

A known flow meter, having a housing with inlet and outlet pipes, is formed on a common axis by a forming and suction nozzle, a flexible tubular end connected to an outlet converter.

a connector having a suction cup

Between nozzles, a breaker kinematically connected to a stationary nozzle and

Installed at the movable end of a flexible tube (USSR a.l. No. 800646, 1991;

The duration of such a meter is not reliable enough.

Also known is a method of measuring liquids and gases, comprising heating the flow of a measuring medium and measuring the temperature difference before and after the preheater (N.G. Farzane et al., Technological Measuring Instruments, M., 1989, p. 238 (in Russian)).

The disadvantage of this measurement is that it is expensive because it requires large amounts of electricity to be heated in large measured streams.

The object of the present invention is to reduce the cost of measurement.

The stated object is achieved by making the following changes to the known method of measuring liquid and gaseous media, which includes preheating the flow and determining the temperature difference before and after preheating:

it subtracts the fixed part, jets it to a constant ratio before measuring and preheating the measurement, subtracts the flow temperature stabilized voltage difference, measures the amperage and determines the total volume of the medium by the formula F = CI, where C = 1,163 U _s (K + l) , where 1,163 is the ratio of the units of electric power to the thermal energy,

U _s - stabilized electric voltage, K - medium flow divider, I - electric current used for heating.

The measurement involves dividing the flow of the medium, heating the portion of the flow set aside for measurement with a constant voltage electrical current to a constant temperature difference and measuring it between the temperature behind and before the _x position, and measuring the current used for heating.

Example of measurement.

The following methods are used to perform the proposed Buddha:

self-manufactured measuring instruments subtracted for measurement total factor K = 100;

medium divider, self-heating electric heater with a power of 0.5 kW;

self-temperature regulator;

temperature sensors - resistive thermometers with 100 M graduation;

ammeter - ammeter.

An example is illustrated in the diagram depicting the arrangement of the instruments and the performance of the measurement.

a flow divider 2 connected to the test flow channel 1 dividing the channel 1 into two tubes 3 and 4. An electric heater 5 is connected to the measuring tube 4 connected to an electric power source 6 via a voltage stabilizer 7 and a temperature regulator 8 connected to a temperature sensor 9, Installed in the measuring tube 4 in front of the heater 5 and with the temperature sensor 10 in the measuring flow tube 4 behind the heater 5. The sensors 9 and 10 are arranged at an equal distance from the center of the heater 5. A temperature regulator 8 through a current measuring device 11 connected to an electric heater 5. Behind the heater 5 and the sensor 10, the tubes 3 and 4 are reconnected into a single channel.

The measurement method involves preheating the flow and detecting the temperature difference therein before and after preheating. Before measuring and warming up by divider 2, divide the flow portion for measurement corresponding to the set factor K = 100, showing the ratio between the flow portion in tube 3 and the portion in tube 4. The stabilized voltage from current source 6 is heated by tube 4 by electric heater 5 traffic share. The temperature difference dT is determined by measuring the flow temperature T ₂ = 150 ° C before the heater 5 with the sensor 9 and the temperature T _L = 151 ° C by the sensor 10 behind the heater 5. The temperature controller 8 maintains a constant temperature difference dT = 1 ° C. current I is measured by a current measuring device 11 with the current I = 2.5 A. The amount of all media transmitted through the channel is determined from the formula F = CI, where C = 1.163 U (K + l). According to this example, the magnitude of the flow of k lu 1 will be F = 1,163.220. (ιϋυ. ..,. 5 = 64.6 tons per hour.

Compared to the prototype, the proposed method lowers the measurement by using less electricity (100 times according to the example given) by heating only part of the total flow to be measured. Electricity and total costs are also saved by maintaining a constant small temperature difference at the measuring points. Measurement and quantification are also cheaply simplified by the measurement of current alone.

Claims (4)

DEFINITION OF INVENTION A method of measuring the amount of liquid and gaseous medium that includes flow heating and temperature difference 5, before and after preheating, characterized in that it divides a portion of the flow into a predetermined ratio between measurement and preheating, heats it with a steady-state electrical current to a constant temperature difference, and measures electric currents 10, and determines the total volume of the medium by the formula F = CI, where C = 1,163 U _s (K + 1), where 1,163 is the ratio of 15 units of electrical and thermal energy, U _s stabilized current, and K is the flow-sharing ratio, I - the current used.