ARCUATE-TUBE-TYPE CORIOLIS FLOW METER AND METHOD FOR DETERMINING SHAPE OF THE SAME

摘要

An arch-shaped tube type Coriolis meter and a method of determining the shape of the Coriolis meter, the meter, wherein two flow tubes are formed in an arch shape formed of a center arc part and linear parts on both sides thereof, the inner diameter of the tubes and a linear length between the end points of the tubes are determined based on a target pressure loss at the maximum flow including pressure losses in a manifold and an arch-shaped flow tubes, a target time phase difference in sine wave output from a vibration detection sensor at the maximum flow, and the target natural frequency of the tubes, the length of the linear part is selected so that a thermal stress due to abrupt change in temperature of measured flow is reduced, and the shape of the flow tubes is determined so that the height of the flow tubes in vertical direction is reduced in an area where the thermal stress becomes generally constant even if the length of the linear part is varied, whereby the shape of the tubes can be determined so that the stress can be suppressed to a specific value and the size can be minimized when the measured fluid causes abrupt change in temperature.