Method for measuring a medium flowing in a pipeline and measurement system therefor

The measuring system for measuring at least one physical, flow parameter, especially a mass and/or volume flow and/or a flow velocity, of an, at least at times, two, or more, phase medium flowing in a pipeline, wherein at least one phase of the medium is fluid, which measuring system comprises:

• an inline measuring device for flowing media, said inline measuring device including a flow pickup, as well as measuring device electronics electrically coupled, at least at times, therewith, and the flow pickup includes at least one measuring tube inserted into the course of the pipeline conveying the medium, especially a measuring tube vibrating, at least at times, during operation;
• and
• a pressure-difference measuring device including a first pressure pickup, especially one arranged at the inlet side of the flow pickup, for registering a first pressure existing in the medium, and a second pressure pickup, especially one arranged at the outlet side of the flow pickup, for registering a second pressure existing in the medium, as well as including measuring device electronics, which, at least at times, is electrically coupled with the pressure pickups and, at least at times, is electrically coupled with the measuring device electronics of the inline measuring device, wherein:
• at least one of said two measuring device electronics, on the basis of a transfer function stored therein, as well as based on the pressures registered by means of the first and second pressure pickups, at least at times, produces measured values of a first kind, which represent, in time following one after the other, especially digitally, the at least one flow parameter of the medium to be measured;
• said measuring device electronics of the inline measuring device produces, at least at times, measured values of a second kind, which represent, in time following one after the other, especially digitally, the at least one parameter, or a measured variable derived therefrom, of the medium in the at least one measuring tube;
• and
• said transfer function determines, at least, how the measured values of the first kind are generated on the basis of the currently registered, first and second pressures, and is adapted to the medium to be measured, taking into consideration at least one of the measured values of the second kind produced by means of the inline measuring device.

The use of a measurement system for measuring a mass-, or volume-, flow and/or a flow velocity of a multiphase, especially a two-phase, medium flowing in a pipeline, including:

• an inline measuring device for flowing media, said inline measuring device including a flow pickup, as well as measuring device electronics electrically coupled, at least at times, therewith, and the flow pickup includes at least one measuring tube inserted into the course of the pipeline conveying the medium, especially a measuring tube vibrating, at least at times, during operation;
• and
• a pressure-difference measuring device including a first pressure pickup, especially one arranged at the inlet side of the flow pickup, for registering a first pressure existing in the medium, and a second pressure pickup, especially one arranged at the outlet side of the flow pickup, for registering a second pressure existing in the medium, as well as including measuring device electronics, which, at least at times, is electrically coupled with the pressure pickups and, at least at times, is electrically coupled with the measuring device electronics of the inline measuring device, wherein:
• at least one of said two measuring device electronics, on the basis of a transfer function stored therein, as well as based on the pressures registered by means of the first and second pressure pickups, at least at times, produces measured values of a first kind, which represent, in time following one after the other, especially digitally, the at least one flow parameter of the medium to be measured;
• said measuring device electronics of the inline measuring device produces, at least at times, measured values of a second kind, which represent, in time following one after the other, especially digitally, the at least one parameter, or a measured variable derived therefrom, of the medium in the at least one measuring tube;
• and
• said transfer function determines, at least, how the measured values of the first kind are generated on the basis of the currently registered, first and second pressures, and is adapted to the medium to be measured, taking into consideration at least one of the measured values of the second kind produced by means of the inline measuring device;
• said use comprising:
• causing the medium to be measured to flow through at least one measuring tube joined into the course of the pipeline, especially a measuring tube which vibrates, at least at times;
• producing at least one measurement signal influenced by at least one physical parameter, especially a flow velocity, a mass flow, a volume flow, a density and/or a viscosity, of the medium in the measuring tube, using an inline measuring device sensor arrangement arranged on the measuring tube and/or in its vicinity and reacting, at least mediately, to changes of the at least one physical parameter of the medium;
• registering pressures, especially static pressures, effective in the medium, in order to repeatedly determine a pressure difference existing in the flow medium, especially a pressure difference existing, at least in part, along the at least one measuring tube;
• and
• producing measured values of a first kind, which represent, especially digitally, following one after the other in time, the at least one flow parameter to be measured for the medium, taking into consideration a currently determined pressure difference for the flowing medium, as well as applying a transfer function, wherein:
• the transfer function at least determines how the measured values of the first kind are generated taking into consideration the pressure difference currently determined for the flowing medium;
• and
• the transfer function is adapted repeatedly to the medium to be measured, taking into consideration the at least one measurement signal produced by means of the sensor arrangement of the inline measuring device.