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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.
O. E. Dwyer, H. C. Berry
Nuclear Science and Engineering | Volume 42 | Number 1 | October 1970 | Pages 69-80
Technical Paper | doi.org/10.13182/NSE70-A19329
Articles are hosted by Taylor and Francis Online.
The results of an analytical study are presented for the case of fully developed heat transfer to fluids in laminar, longitudinal flow through unbaffled rod bundles. The rods represent reactor fuel pins, which consist of ceramic cores encased in a metallic or alloy cladding. The study was based on the thermal boundary condition of uniform heat flux on the inner surface of the cladding. The three prime independent variables are rod spacing (P/D), relative cladding thickness [(r2 − r1)/r2], and relative cladding conductivity (kw/kf). These have been varied over the ranges of 1.05 to 1.30, 0.025 to 0.300, and 0.10 to 4.00, respectively; and the following quantities have been determined as functions of the above variables: rod-average heat transfer coefficients, circumferential variation of outer-surface cladding temperature, same for the inner surface of the cladding, circumferential variation of local heat flux, and finally, circumferential variation of local heat transfer coefficients. It is shown that the assumption of circumferentially uniform heat flux on the inner surface of the cladding is valid for any practical fuel subassembly designs of a sodium-cooled reactor for a central-station power plant. Of the three prime independent variables, the P/D ratio has by far the greatest influence on the heat transfer behavior of the system; and of the remaining two variables, the influence of the kw/kf ratio is about the same as that of the (r2 − r1)/r2 ratio at the lower values of (r2 − r1)/r2, but appreciably greater at the higher values of (r2 − r1)/r2. The greater the P/D ratio and the lower the other two ratios, the more the system behaves like the standard uniform-wall-heat-flux case. The results are all expressed in the form of convenient dimensionless groups and are correlated by simple mathematical expressions, for ready use by the design engineer.
