| 摘要 |
Apparatus for measuring the mass flow rate of a fluid flow utilises a pair of parallel conduits (36, 37) having fixed ends. A driving mechanism (48) is connected between the conduits (36, 37), near their mid-points, for applying transverse oscillations to the conduits at a selected frequency. The fluid whose mass flow rate is to be measured is divided roughly equally and supplied through the parallel conduits (36, 37). A motion sensor (56) upstream of the driving mechanism (48) and another one (58) downstream of the driving mechanism (48) produce signals which have the same frequency as the driving frequency but which lead or lag the driving frequency with regard to phase. This difference in phase is a measurement of mass flow rate. The apparatus can be constructed to self compensate for changes in temperature and/or thermal gradients. |
