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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.
P. V. Gilli
Nuclear Science and Engineering | Volume 22 | Number 3 | July 1965 | Pages 298-314
Technical Paper | doi.org/10.13182/NSE65-A20934
Articles are hosted by Taylor and Francis Online.
Heat transfer and pressure drop characteristics for the flow across banks consisting of plain (unfinned) helical tubes in a multistart arrangement with essentially uniform inclination angles, uniform longitudinal pitches and hence essentially equal heat loads per tube, but with tube pattern changing continuously around the perimeter, have been reduced analytically to the relatively well-known heat transfer coefficients and friction factors for the flow across banks of straight tubes with in-line and regularly staggered tube patterns. For this purpose, correction factors for the effects of tube inclination and of the number of tube rows are introduced. The effective average values of the free flow area—which determine the effective velocity and hence the effective Reynolds number—and the effective arrangement factors are obtained by integration of the local values. The apparent differences of the heat transfer and pressure drop correlations obtained by the two experimental investigations known—the Waagner-Biro experiments on the prototype tube bundle of the steam generators for the OECD High Temperature Reactor Project Dragon and the data of Glaser on regenerator inserts—have been explained quantitatively by the different approach employed for calculating the free flow area. Using the expressions for the effective average free flow area and the correction factors for tube inclination and tube row numbers, agreement of the heat transfer and pressure drop data of both experimental investigations with each other and, what is more, with straight-tube data is achieved. The suggested heat transfer and pressure drop correlations for banks of helical tubes are valid for gases and liquids with Prandtl numbers above 0.1. This range includes applications to steam generators of gas-cooled and liquid-cooled reactors (and cryogenic applications as well). For heat exchangers and steam generators of liquid-metal-cooled reactors—that is for Prandtl numbers of the order of 0.01—a different heat transfer correlation is developed, which is based on available data obtained with liquid metal flowing across banks of straight tubes.
