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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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How to talk about nuclear
In your career as a professional in the nuclear community, chances are you will, at some point, be asked (or volunteer) to talk to at least one layperson about the technology you know and love. You might even be asked to present to a whole group of nonnuclear folks, perhaps as a pitch to some company tangential to your company’s business. So, without further ado, let me give you some pointers on the best way to approach this important and surprisingly complicated task.
O. E. Dwyer, P. J. Hlavac, M. A. Helfant
Nuclear Science and Engineering | Volume 41 | Number 3 | September 1970 | Pages 321-335
Technical Paper | doi.org/10.13182/NSE70-A19090
Articles are hosted by Taylor and Francis Online.
An experimental study of heat transfer to mercury flowing longitudinally through an unbaffled rod bundle was carried out. The purpose was to determine the effect of lateral displacement of a rod on local heat transfer behavior. In a previous paper, the effects of extent and direction of displacement on the rod-average heat transfer coefficient were presented for the displaced rod, on that (or those) toward which it was displaced, and on that (or those) from which it was displaced. Here, the effects of extent and direction of displacement on the peripherally local heating surface temperature, local heat flux, local heat transfer coefficient, and local surface temperature fluctuations are presented for the displaced rod. The test bundle had a P/D ratio of 1.75, and the rods were special electrical heaters. It was found that rod displacement can cause a large circumferential variation in its local heat transfer characteristics. Aside from the P/D ratio, the independent parameters affecting these characteristics are circumferential angle (θ), relative cladding thickness [(r2 − r1)/r2], relative cladding conductivity (kw/kf), and flow rate (Pe). It was found that displacement of a rod can produce circumferential variations in its surface temperature comparable to the average temperature drop from the heating surface to the coolant stream. For a given displacement, this variation increases as average heat flux increases and as (r2 − r1)/r2, kw/kf, and Pe decrease; changes in have the greatest effect, and those in (r2 − r1)/r2 and kw/kf, the least. For a given displacement and flow rate, the greater the surface temperature variation, the less will be the circumferential variation in the local heat flux. Thus, as either cladding thickness or conductivity increase, the variation in the local heat transfer coefficient (and therefore the average) remains about the same. It was found that, as a rod is displaced from its symmetrical position, the local heat transfer coefficients surprisingly decrease at all circumferential points, which partly explains why the rod-average heat transfer coefficient is highly adversely affected by lateral rod displacement. This is only true for liquid-metal coolants.
