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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fermi America looks to go public as NRC accepts COLA for AP1000s
Texas Tech University and Fermi America are now one step closer to realizing their massive vision for the Advanced Energy and Intelligence Campus in Amarillo, Texas, as the Nuclear Regulatory Commission has accepted the first two parts of its combined license application (COLA) for four Westinghouse AP1000s.
Ted Worosz, Seungjin Kim, Chris Hoxie
Nuclear Technology | Volume 190 | Number 3 | June 2015 | Pages 264-273
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT14-71
Articles are hosted by Taylor and Francis Online.
In the two-group interfacial area transport equation (IATE) used to calculate the interfacial area concentration (ai), bubbles are categorized into two groups. Namely, group-I consists of spherical/distorted bubbles, and group-II consists of cap/slug/churn-turbulent bubbles. Robust models for the major bubble interaction mechanisms that cause the transition from purely one-group to two-group flows are essential to the dynamic closure of the two-fluid model with the two-group IATE. Therefore, the present study seeks to establish an experimental database in cap-bubbly flows that highlights this transition to support model development. A four-sensor conductivity probe is used to obtain measurements of local time-averaged two-phase flow parameters, including the void fraction and ai, in vertical-upward air-water two-phase flows in a 5.08-cm pipe. Four flow conditions are investigated at ⟨jf⟩ = 2 m/s with increasing ⟨jg⟩ to study the generation and growth of group-II bubbles. Characteristic features of the local void fraction and ai distributions are discussed. Additionally, axial development of area-averaged void fraction and ai that is indicative of exchange between the bubble groups is presented.
