Development and testing of high-temperature acoustic Doppler flowmeter

Industrial applications of acoustic Doppler flowmeters have recently been increased, in particular in cases of turbulent flow and low-temperature requirements (less than 300/sup 0/F). These flowmeters, however, are not suited for applications in high-temperature and high-viscosity laminar flow streams found in coal-liquefaction plants. This work presents the development and testing of an acoustic Doppler flowmeter developed at the Argonne National Laboratory. The characteristics of this flowmeter are: (1) standoffs to isolate the transducers from the hot pipes; and (2) an electronics system with servo-controlled adjustable filters that can process a Doppler-shift signal spectrum generated by laminar flow conditions.