Heat tranfer metering in puplic indoor pool
MID-testing and more through
clamp-on ultrasonic flow meter
Operation costs in puplic pool checked...
The community Hunxe at the Lower Rhine could no longer bear the operating expenses of its indoor swimming pool. From this plight out a citizens' initiative for the preservation of the indoor pool was formed about 10 years ago. Since October 2007, the "swimming friends" lead with the help of sponsorship, a community grant and self-help to indoor operation continued successfully.
The bath is supplied by a district heating plant from an external energy supplier. A calibrated electromagnetic flowmeter (MAG Meter) measures the heating energy for billing purposes. The external supplier continuously delivers the pool 75 to 80 ° C hot water. The "swimming friends" wonderd on the continiously increasing energy cost and found it worth, to check the existing MAG-Meter. The result suggested a "reflection" on ...
Through Internet searches the "swimming friends" found systecs deltawaveC-P flow ant heat tranfer meter. The non intrusion clamp-on Flowmeters aroused their interest. A date has been agreed in the indoor pool. With deltawaveC-P, the clamp-on ultrasonic meter comparative measurements were made and recorded 25h by the internal data logger. The Excel evaluation shows all measured data.
More than 5% deviation from / of? MID
As Klaus Berels, responsible for the sales systec Contros "Mid West", Wesel, determined with the careful measurement test, dodged the measurement data obtained with the P-deltawaveC more than 5% of the values of the fixed MAG meter. The application engineer says: "This demonstrates a fundamental problem that can tamper the medium-dependent MIDs. The measuring electrodes of MAG-meters are object of deposits over the years of operation and thus they may show significant errors. In this specific case, this could be due to virtually no more removable magetite deposits: Hot water forms magnetite deposits that lead to incorrect measurements. Low pH, high conductivity and the oxygen content of the water result in systems with steel components for such magnetite slurries. Magnetite is ultimately a critical component of deposits in heat meter components. But with the deltawave CP we measure from the outside of the pipe, without direct contact with the medium. Since there is no such measurement errors. Hunxes "swimming friends" now locate possible sources of error and want to make improvements.
|Prinziple||Ultrasonic time of flight|
|Heat mesurement||Included, PT100-Sensors optional|
|Mounting||Fluid-contact-free with clamp on transducers|
|Flow range||-30…30 m/s|
|Measurement||Flow, fluid velocity, heat rate|
|Logger||SD-Card (2 GB)|
|Power supply||Battery and 90-230VAC-Power Supply|