- Media: Ultrasonic Conducting Liquids
- Temperature Range: -40...300 °F
- Accuracy: up to 1%
- Flow Velocities: 0...± 98 ft/sec
- Pipe Sizes: 3/8"...20 feet
- For Use with Common Pipe Materials, with Ultrasonic Conductive Properties, like Steel and Plastics
- Heat Quantity Measurement
The KOBOLD DUC uses the effect of acceleration and decelaration
of acoustic signals traveling in a moving liquid. Two ultrasonic clamp-
on transducers are externally mounted on a pipe and produce an
acoustic path. The transducers send and receive acoustic signals
and the transit times, t1 and t2, are measured by an electronic flow
transmitter. The signal from transducer A towards transducer B is
accelerated by the flow (shorter t1). The return signal from transducer
B to transducer A is decelerated by the flow (longer t2). The difference
between t1 and t2, together with the path length L, can be used
to determine the average flow velocity. This principle is known as
the acoustic time-of-flight principle. The flow is calculated from the
geometry data of the pipe and the flow velocity.
The DUC emits a coded signal pattern into the pipe. The received
signals will be compared with the sent signals and only the signal
pattern, which correlates with the original one, will be used for flow
calculation (cross correlation based signal evaluation). The calculation
of the flow is done with the integrated DSP (digital signal processor).
Thus, the calculation has high sampling rates.
The DSP calculation of the time-of-flight is a pure digital transit time
measurement. It is very precise, completely drift and maintenance
free, and there is no need for recurring calibrations.
Applications Areas
- Power Plants: Cooling Water, District Heating, Pump Protection, Condensate and Boiler Feedwater Measurements
- Water and Waste-Water Industry: Treatment Plant Inflow, Treatment Plant Outflow, Drinking Water Networks, Verification of Water Meters, Pump Protection, Distribution and Consumption Measurements, Leakage Detection
- Facility Management: Hot and Cold Water, Cooling Systems and Air Conditioning Systems, Optimization of Energy Efficiency, Pump Control, Optimization of Heating and Air Conditioning
- Chemical and Petrochemical Industry: Crude Oil and Light Oil, Raw and Waste-water, Aggressive and Toxic Media, Measurement of Heat Carriers (e.g. Thermal Oils)
- Food and Beverage: Correct Hygienic Measurement of Media, Heat Volume Measurement in Energy Supply
Features
- Easy-to-read User Interface with LED Backlight, QVGA Display
- User Interface Control with 6 Buttons
- Quick-Mount-System with Space Bar for Ultrasonic Transducers, 1 MHz and 2 MHz
- AFC Compensation Algorithm: Compensates for Influences of Changing Media Temperatures
- Reynolds Compensation: Compensates for Influences of Media Viscosity
- Ultrasonic Transducers and Technology: Reduces Signal Echoes and Dispersion Effects, Having a Positive Effect on the Signal to Noise Ratio
- 2 Channel Operation, with Stationary Transmitter
Flow Transmitters
DUC-xP: Portable Flow Transmitter
Flow measurement, thermal output, and heat quantity
measurement is possible for one measurement point with a
pair of ultrasonic transducers in combination with a pair of
PT100 temperature sensors. Other features of the DUC-xP
transmitter are battery operation, integrated data logger, and a
stable aluminum / ABS housing.
DUC-xF: Stationary 1-Channel Flow Transmitter
Flow measurement, thermal output, and heat quantity
measurement is applicable for one measurement point in
combination with one pair ultrasonic transducers and one pair
PT100.
DUC-xF: Stationary 2-Channel Flow Transmitter
Flow measurement is applicable for one or two different
measurement points with two pairs of ultrasonic transducers.
DUC-xF 2-channel version supports different mathematical
operations like CH1+CH2, CH1-CH2, (CH1+CH2)/2; due to
the appliance of two mounted pairs of ultrasonic-transducers.
Opposite mounting of 2 pairs of transducers on the same pipe
will increase the accuracy of measurement, and a redundancy
operation is possible where disruptive influences of gaseous
flow profile will be compensated. Thermal output and heat
quantity measurement is only supported in operation mode
(CH1+CH2)/2.
DUC-W Standard Ultrasonic Transducers
The ultrasonic transducers are mounted onto the piping and transmit and receive the ultrasonic signals that are used in the flow transmitter
to calculate the volumetric flow rate.