Basics of industrial flow measurements 7

My apologies for adding this article with delay.

Talking about more methods to measure flow we are now further discussing two unique methods of flow measurement which use new developed technology for the ultimate results of precision flow measurement.

Thermal mass flow meter is also used in industry to measure the flow. It uses a combination of heating elements and temperature sensors upstream and downstream of the heating element and determine the flow. Used mainly for clean gases, oxygen, helium, argon, nitrogen, compressed air or natural gas. Again this flow measurement device is for gases and those with predetermined specific heat and density. Change in gas composition affects the measurement accuracy. It is also known as thermal dispersion type flow meter. It is widely employed in medical equipment also as it is capable of detecting minor flows like in respiratory devices or anesthesia dispensers.

.Now, is there a measurement system which can measure, gas, liquids and water mixture in a single device?

Multiphase flow meters MPFM as these are known are now very popular in oil and gas upstream industry where this single meter calculates different phases of fluid in a single stream, like oil wells outlet, which has gases, oil and water in the same stream. Pressure and temperature sensors augment the flow calculations and it uses gamma densitometers with venturi type flow measurement device built in a single meter.

Magnetic resonance, the same principle used in medical MRI machines is used in MPFM, to magnetize the fluid and subsequently its atoms are excited by radio frequency in measuring chamber.

The hydrogen atoms present in the gas, liquid and water resonate and send back echoes which are recorded and since each resonation is different for the phases, the total amount of gas, liquid and water can be determined form this spectrum, which is further compensated for pressure and temperature giving precise amount of each fluid in the stream.

Here we conclude our article on flow measurements though some other type of flow measurement devices exist but are not very common in industry.

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