Examinando por Autor "Bell, Stephanie"

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An investigation of the comparative performance of diverse humidity sensing techniques in natural gas
(Elsevier, 2015-02-21) García Gallegos, Jaime; Benyon Puig, Robert; Ávila, Sara; Benito, Angel M.; Gavioso, Roberto Maria; Mitter, Helmut; Bell, Stephanie; Stevens, Mark; Böse, Norbert; Ebert, Volker; Heinonen, M.; Peruzzi, Andrea; Bosma, Rien; Val´ková, Miroslava
Moisture content is a key factor regardless of the activity carried out inside the natural gas industry (production, processing, transmission, etc.). Not only does the efficiency of the final product, known as heating value, decrease when the water content is high, but it can also trigger potentially dangerous conditions due to the formation of hydrates, that can block pipelines and damage pumping devices and produce other negative effects. For these reasons, accurate measurement and control of humidity is absolutely essential. However, current practice for such moisture measurements is for the devices to be calibrated at atmospheric pressure and in nitrogen or air as the matrix gas, conditions that vary significantly from those present in the actual industrial process. For that, eleven hygrometers based on different measurement principles (chilled-mirror, electrolytic sensor, a spectroscopic analyzer, polymeric and metal oxide humidity sensors) have been compared at facilities of the main carrier of natural gas in Spain, using natural gas at absolute pressures between 0.1 MPa and 6 MPa, and for a range of water content from 13 ppmv to 250 ppmv. Their relative performance is described in terms of the response times, long term stability, hysteresis and behaviour under large pressure changes. Most instruments, exceptions are detailed in the article, show good behaviour regarding response time, hysteresis and under sudden pressure changes. In contrast, drift can be identified in most of the aluminium oxide probes tested.
Acceso Abierto
Report from interlaboratory comparison of air thermometer calibration procedures
(Zenodo, 2023-11-24) Olsen, Åge Andreas Falnes; MErlone, Andrea; MacLochlainn, Dubhaltach; García Izquierdo, Carmen; Voldán, Michal; Pavlasek, P.; Oguz Aytekin, S.; Carrol, Peter; Bell, Stephanie; Spahiu, Iska; Hofstätter-Mohler, Christina; Nielsen, Jan; Bergerund Reidun, Anita; Rothmund, Peter; Dobre, Miruna; Van den Berghe, Debby; Bojkovski, Jovan; Raab, Patrick; Mitter, Helmut; Vukicevic, Tanja; Kowal, Alexandra; Dobosz, Justyna; Cohodarevic, Semir; Högström, Richard; Turzó-András, Emese; Simic, Slavica; Giorgin, Eric; Jarosz, Rafal; Kokkini, Evmorfia; Maniur, M. I.; Deschermeier, Regina; Eckerleben, Carolyn; Bubser, Florian; de Lucas Veguillas, Javier; García Gallegos, Jaime; Smorgon, Denis; Holmsten, Magnus
The interlaboratory comparison (ILC) was initiated in 2019 as an important first step in the EURAMET project 1459. The aim of the ILC was first and foremost to gain knowledge later used in developing guidelines for air thermometry, particularly within the realm of calibration and dissemination of the temperature scale. While the ILC protocol asked the participants to report a set of main data that followed a rather strict formular, they were also encouraged to perform different characterisation experiments and to explore different strategies for calibration. The idea was to have a set of common baseline data and analyse them in a traditional ILC framework, but at the same time gather exploratory data that could help advance the knowledge in air temperature metrology. The results were intended to be used as input to guidance documents for the calibration of thermometers for air temperature measurements, and possibly to some initial best practice guides for practical air thermometry in the field.