Development of a Mass Flow Rate Meter Based on Coriolis Effect

Abstract

In many process industries, mass flow rate is the desired parameter rather than the volume flow rate. There are two approaches to measure mass flow rate. In the first approach, volume flow rate is measured and then it is multiplied with density. The second approach utilizes the flow metering concepts which are sensitive to mass flow rate. The work presented here falls in the second category. Here, the fluid is made to pass through a vertical U-tube and at the same time it is vibrated by a shaker. The rotary motion produced as a result of vibration causes Coriolis force to act on the tube and causes it to twist. Because of the twisting action, the two limbs of the tube do not pass through the mean position simultaneously. The resulting time lag (Δt) is measured with the help of an 8085 microprocessor and two proximity pick-ups. Mass flow rate is directly proportional to time lag (Δt) and is calculated and displayed subsequently after multiplying time lag (Δt) with a constant of proportionality. The work presented in the paper is carried out as a project assignment by undergraduate students at the final year stage of Bachelor of Engineering degree in Mechanical Engineering. It is expected that the work would be quite useful to the students from the point of view of applying the acquired knowledge to actual engineering situations.