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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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From operator to entrepreneur: David Garcia applies outage management lessons
David Garcia
If ComEd’s Zion plant in northern Illinois hadn’t closed in 1998, David Garcia might still be there, where he got his start in nuclear power as an operator at age 24.
But in his ninth year working there, Zion closed, and Garcia moved on to a series of new roles—including at Wisconsin’s Point Beach plant, the corporate offices of Minnesota’s Xcel Energy, and on the supplier side at PaR Nuclear—into an on-the-job education that he augmented with degrees in business and divinity that he sought later in life.
Garcia started his own company—Waymaker Resource Group—in 2014. Recently, Waymaker has been supporting Holtec’s restart project at the Palisades plant with staffing and analysis. Palisades sits almost exactly due east of the fully decommissioned Zion site on the other side of Lake Michigan and is poised to operate again after what amounts to an extended outage of more than three years. Holtec also plans to build more reactors at the same site.
For Garcia, the takeaway is clear: “This industry is not going away. Nuclear power and the adjacent industries that support nuclear power—and clean energy, period—are going to be needed for decades upon decades.”
In July, Garcia talked with Nuclear News staff writer Susan Gallier about his career and what he has learned about running successful outages and other projects.
Joseph L. Bottini, Caleb S. Brooks
Nuclear Technology | Volume 209 | Number 12 | December 2023 | Pages 1987-2001
Research Article | doi.org/10.1080/00295450.2022.2156244
Articles are hosted by Taylor and Francis Online.
The Two-Fluid Model (TFM) has long been the backbone of engineering-scale two-phase flow simulation in system-analysis codes and computational fluid dynamics codes. The classical TFM is limited in how it can capture the differences in the transport of small and large bubbles. The two-group TFM provides the ability to specify the unique transport characteristics of small and large bubbles separately. Expanding to two sets of conservation equations for the two bubble groups presents the additional challenge of bubble group accounting as bubbles can cross the group boundary. The three mass transfer terms in the two-group TFM are evaluated for flashing, condensing, and boiling flows using a partitioning method. The axial trends in the source terms are examined for these flow conditions with the available intergroup models. Two-group interphase models are implemented and evaluated against experimental data for flashing, condensing, and boiling flows with accurate two-group results. The capabilities of the two-group TFM are evaluated for these flow types, demonstrating the ability to predict two-group vapor properties without the need for flow regime transitions.
