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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 40 | Number 2 | May 1970 | Pages 317-330
Technical Paper | doi.org/10.13182/NSE70-A19692
Articles are hosted by Taylor and Francis Online.
This paper summarizes the results of an analytical study carried out for the purpose of determining the effects of cladding thickness and conductivity on fully developed heat transfer to liquid metals flowing in-line through unbaffled rod bundles. The study is based on slug flow and the assumption that the heat flux on the inner wall of the cladding is uniform in all directions. It was shown earlier that slug-flow results for liquid metals are very similar to those for turbulent flow in practical Pe ranges, particularly when the results are put in certain dimensionless forms, and it is shown in the present study that the assumption of circumferentially uniform heat flux on the inner wall of the cladding is perfectly valid for any practical nuclear-reactor design for a central-station power plant. The problem required the simultaneous solution of the differential energy equations for both the coolant and cladding, which are coupled by the local temperature and heat-flux conditions existing at the coolant-cladding interface. There are three prime independent variables: rod spacing (P/D), relative cladding thickness (r2 − r1)/r2, and relative cladding conductivity (kw/kf). These have been varied over the ranges 1.05 to 1.30, 0.025 to 0.300, and 0.10 to 4.00, respectively. The following quantities have been calculated as functions of the above independent variables: rod-average heat transfer coefficients, circumferential variation of outer-surface cladding temperature, the same for the inner surface, circumferential variation of local heat flux, and finally, circumferential variation of local heat-transfer coefficient. 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. It is found that, 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 that, of the remaining two variables, the thermal conductivity ratio, kw/kf, has appreciably more influence than the relative-cladding-thickness ratio (r2 − r1)/r2. The higher the P/D ratio and the lower the (r2 − r1)/r2 and kw/kf ratios, the more the system behaves like the uniform-wall-heat-flux case; and it is interesting to note that in many practical situations the simple uniform-wall-heat-flux assumption is quite adequate.
