Speaker
Abigail Alexandra O'Rourke
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
Description
Custom ultrasonic instruments have been developed for simultaneous monitoring of binary gas mixture and flow in the ATLAS Inner Detector. Sound transit times are measured in opposite directions in flowing gas. Flow rate and sound velocity are respectively calculated from their difference and average. Gas composition is evaluated in real-time by comparison with a sound velocity/composition database, based on the direct dependence of sound velocity on component concentrations in a mixture at known temperature and pressure.
Five devices are integrated into the ATLAS Detector Control System. Three instruments monitor coolant leaks into N2 envelopes of the SCT and pixel detectors. Resolutions better than $\pm5\times10^{-5}$ and $\pm10^{-4}$ are respectively seen for C3F8 and CO2 leak concentrations in N2. A fourth instrument detects sub-percent levels of air ingress into the C3F8 condenser of the new thermosiphon coolant recirculator. Following extensive studies a fifth instrument was built as an angled sound path flowmeter to measure the high returning C3F8 vapour flux (~1.2 kg/s). A precision of < 2% F.S. for flows up to 15 m/s was demonstrated. This device can also monitor C3F8 and C2F6 concentrations to better than $\pm3\times10^{-3}$. These blends allow for lower temperature silicon tracker operation.
The instrument has many potential applications where continuous binary gas composition measurement is required, including hydrocarbon and anaesthetic gas mixtures.
Primary author
Abigail Alexandra O'Rourke
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
Co-authors
Alexander Bitadze
(University of Manchester (GB))
Alexandre Rozanov
(CPPM, Aix-Marseille Université, CNRS/IN2P3 (FR))
Ben Pearson
(University of Oklahoma (US))
Beniamino Di Girolamo
(CERN)
Cecile Deterre
(Deutsches Elektronen-Synchrotron Hamburg and Zeuthen (DE))
Cecilia Rossi
(Universita e INFN Genova (IT))
Cyril Degeorge
(Indiana University (US))
Dave Robinson
(University of Cambridge (GB))
Didier Lombard
(CERN)
Gilles Favre
(CERN)
Gregory Hallewell
(Centre National de la Recherche Scientifique (FR))
Hasib Ahmed
(University of Oklahoma (US))
Mr
Joel Young
(University of Oklahoma)
Koichi Nagai
(University of Oxford (GB))
Lukasz Zwalinski
(CERN)
Martin Doubek
(Czech Technical University (CZ))
Michele Battistin
(CERN)
Mike Strauss
(University of Oklahoma (US))
Muhammad Alhroob
(University of Oklahoma (US))
Olivier Crespo-Lopez
(CERN)
Pierre Bonneau
(CERN)
Richard Bates
(Department of Physics and Astronomy-University of Glasgow)
Romain Vaglio
(Inst. Universitaire de Technologie d'Annecy (FR))
Rusty Boyd
(University of Oklahoma (US))
Sergei Katunin
(B.P. Konstantinov Petersburg Nuclear Physics Institute - PNPI ()
Stephane Berry
(CERN)
Stephen Mcmahon
(STFC - Rutherford Appleton Lab. (GB))
Vic Vacek
(Czech Technical University (CZ))
