Abstract: A system and method for measurement of flow parameters in a sewer pipe that may be partially or completely filled. Flow parameters may include flow velocity, flow volume, depth of flow and surcharge pressure. Measurements are taken from a sensor head installed on the inside of the pipe at the top of the pipe approximately the larger of at least 1 foot or 1 pipe diameter upstream of a pipe opening. Flow velocity may be measured by two different technologies. The technology employed depends on whether or not the pipe is full. If the pipe is not full then flow velocity may be measured, for example, using a wide beam, ultrasonic, diagonally downward looking Doppler signal that interacts with the surface of the flow. If the pipe is full, then flow velocity may be measured using, for example, an average velocity Doppler sensor, a peak velocity Doppler sensor or an ultrasonic velocity profiler.

Abstract: The present invention relates to a system and method for measurement of flow velocity using the transmission of a sequence of coherent pulsed ultrasonic signals into the flow, and sampling the received response signal at a predetermined delay time relative to the pulse transmission that does not correspond to the signal transmission time. The sampling may be coherent with a frequency offset from the coherency frequency of the pulses. The received signal samples are then spectrally processed, typically by a Fourier process, to generate a frequency domain data set. A threshold technique is used on the frequency domain data set to determine a peak Doppler shift. Average velocity is then obtained by multiplying the peak Doppler shift by a factor, for example, 0.90. In one embodiment, the transmit pulse and receive samples are interleaved by alternating between transmitting a pulse and, after a delay, sampling the received signal.

Abstract: The present invention relates to a system and method for measurement of flow velocity using the transmission of a sequence of coherent pulsed ultrasonic signals into the flow, and sampling the received response signal at a predetermined delay time relative to the pulse transmission that does not correspond to the signal transmission time. The sampling may be coherent with a frequency offset from the coherency frequency of the pulses. The received signal samples are then spectrally processed, typically by a Fourier process, to generate a frequency domain data set. A threshold technique is used on the frequency domain data set to determine a peak Doppler shift. Average velocity is then obtained by multiplying the peak Doppler shift by a factor, for example, 0.90. In one embodiment, the transmit pulse and receive samples are interleaved by alternating between transmitting a pulse and, after a delay, sampling the received signal.

Abstract: A sonic-type fluid flow measuring system wherein reflections or echoes of an ultrasonic acoustic emitter (9) are sensed and typically comprise a number of frequencies representative of a number of discrete velocities of flow in a volume of fluid. As a sample, they simply appear as a voltage plot as a function of time and wherein the time width of a given signal excursion relates to the frequency of a given signal. Thereafter, this time domain signal sample is converted to a frequency domain sample whereby the presence and magnitude of each frequency component, or velocity component, is isolated, this being typically done by what is known as a Fast Fourier Transform. The highest frequency, velocity, signal from each of a rapid succession of samples is then obtained and stored in a memory (38). The highest and lowest of these are then discarded, and the remaining are averaged to obtain more likely representations of velocity.

Abstract: A sonic-type fluid flow measuring system wherein reflections or echoes of a burst 103 of ultrasonic energy from an ultrasonic acoustic emitter 9a are sensed and typically comprise a number of frequencies representative of a number of discrete velocities of flow in a volume of fluid. A receiver transducer 13a is gated to receive echoes from a selected volume of fluid 104 a selected distance from transducer 13a. Thereafter, this time domain signal sample is converted to a frequency domain sample whereby the presence and magnitude of each frequency component, or velocity component, is isolated, this being typically done by what is known as a Fast Fourier Transform unit 42a, obtaining a frequency domain waveform representative of average flow velocity.

Abstract: A sewer flow monitoring system wherein the volume of flow is determined from the depth of fluid in a pipe together with the average velocity of flow through the pipe as determined by detecting the peak velocity from particles flowing in sewage at different velocities and then determining average velocity to be approximately 90% of the peak velocity.

Abstract: A sonic-type fluid flow measuring system wherein reflections or echoes of an ultrasonic acoustic emitter are sensed and typically comprise a number of frequencies representative of a number of discrete velocities of flow in a volume of fluid. As a sample, they simply appear as a voltage plot as a function of time and wherein the time width of a given signal excursion relates to the frequency of a given signal. Thereafter, this time domain signal sample is converted to a frequency domain sample whereby the presence and magnitude of each frequency component, or velocity component, is isolated, this being typically done by what is known as a Fast Fourier Transform. The highest frequency, velocity, signal from each of a rapid succession of samples is then obtained and stored in a memory. The highest and lowest of these are then discarded, and the remaining are averaged to obtain more likely representations of velocity.

Abstract: A measurement and control system for employment with a plurality of significantly spaced process access locations wherein a single cable extends in a loop by these access locations, and both ends of the cable are terminated at a central controller. The cable consists of a solid, conductive, outer housing and four spaced conductors within the housing, the housing being otherwise filled with a dielectric material. Data units are positioned at each access location, and each data unit is configured to supply and receive, or one of the other, discrete data by being coupled to the cable, two of the conductors of the cable furnishing power for the data unit, and the other two providing communications. Certain of the data units employ transducers to measure a single physical state. Outputs from these transducers, in analog form, are serialized, converted to digital data, cross-compared to determine off scaled readings, and the good readings averaged.

Abstract: A measurement and control system for employment with a plurality of significantly spaced process access locations wherein a single cable extends in a loop by these access locations, and both ends of the cable are terminated at a central controller. The cable consists of a solid, conductive, outer housing and four spaced conductors within the housing, the housing being otherwise filled with a dielectric material. Data units are positioned at each access location, and each data unit is configured to supply and receive, or one of the other, discrete data by being coupled to the cable, two of the conductors of the cable furnishing power for the data unit, and the other two providing communications. Certain of the data units employ transducers to measure a single physical state. Outputs from these transducers, in analog form, are serialized, converted to digital data, cross-compared to determine off scaled readings, and the good readings averaged.

Abstract: A measurement and control system for employment with a plurality of significantly spaced process access locations wherein a single cable extends in a loop by these access locations, and both ends of the cable are terminated at a central controller. The cable consists of a solid, conductive, outer housing and four spaced conductors within the housing, the housing being otherwise filled with a dielectric material. Data units are positioned at each access location, and each data unit is configured to supply and receive, or one of the other, discrete data by being coupled to the cable, two of the conductors of the cable furnishing power for the data unit, and the other two providing communications. Certain of the data units employ transducers to measure a single physical state. Outputs from these transducers, in analog form, are serialized, converted to digital data, cross-compared to determine off scaled readings, and the good readings averaged.

Abstract: A sewer flow monitoring system wherein the depth of fluid in a pipe is measured in pairs of transmitter-receiver ultrasonic ranging transducers. Each measurement sample is tested against a selected range criteria and against other samples, and the determined good samples are then averaged. Short range detection capability is obtained by varying the response of signal processing wherein an attenuating effect decreases with time following a transmitted pulse.