Needle shaped conductivity probes with integrated micro-thermocouple and their application in rapid condensation experiments with non-condensable gases
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H.-M. Prasser
Abstract
The present paper deals with advanced conductivity probes for local void measurements, which were equipped with a microthermocouple, which is integrated into the probe at the place of the electrode wire. These probes were used for rapid transient condensation tests in a heat exchanger pipe immersed into a cooling water tank. The experiments serve as data sources for the validation of thermal-hydraulic system codes concerning the modelling of the condensation, particularly with respect to the behaviour and effect of non-condensable gases. The present tests were carried out at the pressurizer test facility DHVA of the University for Applied Sciences in Zittau/Görlitz, IPM serving as steam source. The slightly downwards inclined condensation tube was connected to the head of the pressure vessel and supplied with steam in this way. The application of a new type of two-phase instrumentation has revealed details about the transient condensation process. Since tests were performed with and without the presence of a non-condensable gas (air), the effect of the gas could be studied. The merits of the probes lie in the ability to distinguish between steam and gas. Without the synchronous temperature and void measurement performed by the probes it would have not been possible to clarify the physical background of the temperature jumps found during the experiments with the non-condensable gas.
Abstract
Der Beitrag behandelt fortgeschrittene Leitfähigkeitssonden für lokale Dampfgehaltsmessungen, die anstelle des normalerweise verwendeten Elektrodendrahts mit einem Mikrothermoelement ausgestattet sind. Diese Sonden wurden für schnelle transiente Kondensationsexperimente in einem Wärmeübertragerrohr verwendet, das sich in einem Kühlwassertank befand. Die Versuche dienen als Datenquelle für die Validierung von Thermohydraulik-Codes im Hinblick auf das Verhalten von nichtkondensierbaren Gasen und deren Einfluss auf Kondensationsvorgänge. Die Experimente wurden an der Druckhalterversuchsanlage der Hochschule Zittau/Görlitz, IPM durchgeführt, die als Dampfquelle diente. Das leicht nach unten geneigte Kondensator-Rohr wurde mit dem Kopf des Druckhalters verbunden und so mit Dampf beaufschlagt. Die Anwendung der neuartigen Sonden hat neue Details über den transienten Kondensationsvorgang ergeben. Da die Versuche mit und ohne Anwesenheit von Luft im Versuchsrohr durchgeführt wurden, konnte der Einfluss des nichtkondensierbaren Gases studiert werden. Die Vorzüge der Sonden liegen in der Fähigkeit, zwischen Dampf und Inertgas zu unterscheiden. Ohne die simultane Messung von Temperatur und Phasenanteil wäre eine Erklärung der beobachteten Temperatursprünge nicht möglich gewesen.
Acknowledgements
The present work was supported by the German Federal Ministry of Economics and Labour within the reactor safety research programme.
References
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© 2003 Carl Hanser Verlag, München
Articles in the same Issue
- Frontmatter
- Calendar of events · veranstaltungskalender
- Summaries/Kurzfassungen
- Editorial
- Measurement Techniques for Steady and Transient Multiphase Flows
- Effects of a flow obstacle on liquid film thickness in relation with CHF enhancement
- Books · Bücher
- Ultra-fast x-ray tomography for multi-phase flow interface dynamic studies
- Water hammer and cavitational hammer in process plant pipe systems
- Innovative transient-proof hydrostatic level measuring method
- First experiments on visualisation of two-phase high pressure and temperature flows using an ultrasonic mesh sensor
- Books · Bücher
- Concentration and temperature measurements by means of Raman spectroscopy in case of condensation with non-condensable gas
- Needle shaped conductivity probes with integrated micro-thermocouple and their application in rapid condensation experiments with non-condensable gases
- Books · Bücher
- Letter to the Editor
- The critical radius of reflected spheres
- Note · Mitteilung
Articles in the same Issue
- Frontmatter
- Calendar of events · veranstaltungskalender
- Summaries/Kurzfassungen
- Editorial
- Measurement Techniques for Steady and Transient Multiphase Flows
- Effects of a flow obstacle on liquid film thickness in relation with CHF enhancement
- Books · Bücher
- Ultra-fast x-ray tomography for multi-phase flow interface dynamic studies
- Water hammer and cavitational hammer in process plant pipe systems
- Innovative transient-proof hydrostatic level measuring method
- First experiments on visualisation of two-phase high pressure and temperature flows using an ultrasonic mesh sensor
- Books · Bücher
- Concentration and temperature measurements by means of Raman spectroscopy in case of condensation with non-condensable gas
- Needle shaped conductivity probes with integrated micro-thermocouple and their application in rapid condensation experiments with non-condensable gases
- Books · Bücher
- Letter to the Editor
- The critical radius of reflected spheres
- Note · Mitteilung
