Development of a reduced model of formation reactions in Zr-Al nanolaminates

Citation data:

Journal of Applied Physics, ISSN: 1089-7550, Vol: 116, Issue: 23

Publication Year:
2014
Usage 92
Downloads 49
Full Text Views 26
Abstract Views 16
Link-outs 1
Captures 12
Readers 12
Citations 6
Citation Indexes 6
Repository URL:
http://hdl.handle.net/10754/552276
DOI:
10.1063/1.4903816
Author(s):
Vohra, Manav; Winokur, Justin; Overdeep, Kyle R.; Marcello, Paul; Weihs, Timothy P.; Knio, Omar M.
Publisher(s):
AIP Publishing
Tags:
Physics and Astronomy
article description
A computational model of anaerobic reactions in metallic multilayered systems with an equimolar composition of zirconium and aluminum is developed. The reduced reaction formalism of M. Salloum and O. M. Knio, Combust. Flame 157(2): 288-295 (2010) is adopted. Attention is focused on quantifying intermixing rates based on experimental measurements of uniform ignition as well as measurements of self-propagating front velocities. Estimates of atomic diffusivity are first obtained based on a regression analysis. A more elaborate Bayesian inference formalism is then applied in order to assess the impact of uncertainties in the measurements, potential discrepancies between predictions and observations, as well as the sensitivity of predictions to inferred parameters. Intermixing rates are correlated in terms of a composite Arrhenius law, which exhibits a discontinuity around the Al melting temperature. Analysis of the predictions indicates that Arrhenius parameters inferred for the low-temperature branch lie within a tight range, whereas the parameters of the high-temperature branch are characterized by higher uncertainty. The latter is affected by scatter in the experimental measurements, and the limited range of bilayers where observations are available. For both branches, the predictions exhibit higher sensitivity to the activation energy than the pre-exponent, whose posteriors are highly correlated.