R. Radhakrishnan et al. / Energy Conversion and Management 44 (2003) 771–780
779
account in the experimental results, the experiments over predict the flux and hence the shrinkage
rate by up to a factor of 10. This effect could account for the discrepancy between the experiments
and the model. In summary, our model together with our computed DH [33], provides a rea-
sonably good estimate of the hydrate film thickness and the CO2 flux under steady state condi-
tions. It should be noted that the close agreement between the model and experiments goes to
validate the diffusion mechanism proposed by Demurov et al. [33]. Other possible defect struc-
tures, viz. grain boundaries and dislocations, could also affect diffusion in the hydrate layer. Our
results indicate, however, that such effects may be negligibly small compared to the water vacancy
and CO2 hopping mechanism.
Acknowledgements
The authors acknowledge funding from the DOE Office of Science and the DOE Center for
Research on Ocean Carbon Sequestration (DOCS).
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