Effects of pressure on thermal transport in plutonium oxide powder

Abstract

Radial temperature profiles of plutonium dioxide powder in a cylindrical vessel were measured over a pressure range of 0.055 to 334.4 kPa with two different fill gases, helium and argon. The powder provides a very uniform self-heating medium for analysis. A thermal conductivity model was developed for heat conduction in the fine ceramic powder. Most literature models make limiting assumptions about powder characteristics that do not hold for this material. Despite the powder particles' complex geometry, the proposed model correctly reproduces the powder temperature profiles over the wide pressure range for both fill gases.

Delocalization and occupancy effects of 5f orbitals in plutonium intermetallics using L3-edge resonant X-ray emission spectroscopy

“…The PuO 2.06 sample started from a well characterized stock [28] that was subsequently calcined and delivered in a pure helium atmosphere, then handled and epoxied in dry inert atmospheres (He and Ar). Given this treatment, the uptake of water by the oxide should be negligible.…”

“…In particular no Pu 2 O 3 peaks were observed. Further details regarding this sample have been previously reported [28].…”

Analysis of the Rate of Adsorption of Moisture Onto Plutonium Oxide Powders

“…Moisture adsorption creates significant temperature gradients in the product can due to its larger size. These temperature gradients were modeled using an effective thermal conductivity correlation for plutonium dioxide powder developed by Bielenberg et al 8 Because the primary focus of this study is mass transfer and adsorption, details of the Bielenberg et al correlation and the heat transfer model are not provided.…”

A Method for Estimating Gas Pressure in 3013 Containers Using an Isp Database Query

“…The volume occupied by the convenience container and material must be subtracted from the inner container's inner volume as: The inner can volume is site specific. The volumes used in these calculations are the minimum volumes shown in 25°C is the ambient temperature, 273 converts degrees Celsius to Kelvin, 1.6(oK/w) x Q(w) is the increase going from the outer container wall to the inner container wall, and 3(K/w) x Q(w) is the average increase due to the material using the thermal model derived by Bielenberg et al (2006).…”