Method and apparatus for measuring heat transfer in small diameter pipes using acoustic signals

摘要

Methods and apparatae for metering energy consumption in a mass transfer heat delivery system using acoustic signals. A first type of method uses the phase difference between two simultaneously generated acoustic signals to determine the flow rate of liquid through a station of the heat delivery system. A first transducer and second transducers are used to transmit the first and second acoustic signals, respectively, through the liquid in response to an applied drive signal. The drive signal is removed from the first and second transducers such that the first and second transducers may be used to detect the arrival of the second and first acoustic signals, respectively. A phase detector measures the phase difference between the two acoustic signals as detected by the first and second transducers. A second type of method uses time lag analysis. A first transducer is used to transmit an acoustic signal through the liquid towards a second transducer in response to an applied drive signal. The drive signal is removed from the first transducer such that the first transducer may act as a receiver. The first and second transducers are arranged relative to one another such that echoes bounce back and forth between the transducers. To overcome effects of the conversion delays of the transducers, the arrival times of echoes when performing the time lag analysis. Both the temperature of liquid and the flow rate of liquid may be determined using the time lag analysis method.