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Subject: low inlet mass flow qualities gen. Прошу помощи специалистов нефтегаза. Попалось название научной статьи (ее текста нету): Extended w-method, applicable for low inlet mass flow qualities Это "расширенный метод, применимый для потока с низким массовым паросодержанием на входе"? Или совсем не так? |
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Introduction Two-phase mass flow rates through throttling devices aregenerally calculated based on simplified geometries. Mostoften a nozzle is considered. The result is then corrected byan experimentally determined factor, i.e. a friction or dis-charge coefficient, to account for any deviation in the flowdue to the real geometry– an orifice, a venturior valve. Cur-rently the only standards which exist are for the sizing of safety valvesgiven in API 520 [1] and ISO 23521[2]. Theseare based on the world wide accepted ω-method developedby J.C. Leung, [3,4], and recommended by the DIERS In-stitute [5]. Several classical sizing text books also makereference to it [6,7]. One of the major advantages of thismethod is its use of known or easily measurable propertydata at inlet stagnation condition of the safety valve.The use of the ω -method for saturated two-phase flowgenerally leads to conservative sizing results, because ho-mogeneous equilibrium flow through the safety valve isassumed. However, if an initially sub-cooled or a boilingliquid with a low mass flow quality has to be consideredat the inlet of a safety valve, it is well known, that themethod provides an in-acceptable over-estimation of the re-quired size [e.g. 8,9]. As an alternative, the Henry/Fauskemodel [10] which is based on a more accurate fit to ex-perimental data can be applied in such situations to cal-culate the mass flow rate. Henry and Fauske also pro-posed a boiling delay factor to account for the thermalnon-equilibrium of the fluid and get excellent results whencompared with the flow through nozzles. Unfortunately, themodel of Henry/Fauske is based on physical property datawhich are only rarely available in industry and additionallyit is more complicate to use than the ω-method. Казалось бы, причем здесь пар? low - низкий inlet - впуск mass flow - массовый расход qualities - характеристики |
| Спасибо, познавательно! |
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+ не познавательно, но может сгодиться. Leung J.C., Epstein M. A generalized correlation for two-phase nonflashing homogenous choked flow// Trans. ASME. J. Heat Transfer Научная библиотека диссертаций и авторефератов disserCat http://www.dissercat.com/content/issledovanie-i-raschet-struinogo-nasosa-s-gazozhidkostnoi-ezhektiruemoi-sredoi#ixzz28hTv6GDH |
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